At Camera Obscura and World of Illusions

Transcription

At Camera Obscura and World of Illusions
A
Teacher’s
Guide
To
Edinburgh
3rd Edition
2008
Table of contents
Introduction
p.4
1
Acknowledgements
Camera Obscura and World of Illusions
Visit Planner
Making the Most of your Visit
p.5
p.6
p.7
p.10
Level B
Light and Dark
Blindfold Exercise, Area and House Walks, Drawing Night
and Day, Research Projects, What Colour is Inside the Box?,
The Camera Obscura, Rainbow Making.
Mind over Matter
p.20
Flip book, Thaumatrope, Zoetrope, Praxinoscope,
Mutoscope.
Seeing 3D
Binocular Stereovision, Stereoscope/3D Viewers,
Anaglyphs, Holograms, Mirror 3D, Telescopic Peepshow.
p.11
p.24
Level C
Kaleidoscope Magic
p.31
Hall of Mirrors
p.35
Morphing Faces
p.41
Two Mirror Reflections, Making a Kaleidoscope, Giant
Kaleidoscope, Large Kaleidoscope, Fibre Optic Kaleidoscope,
Kaleidosphere.
Exploring Mirrors, Mirror Drawing, Bendy Mirrors,
Shake Hands, Infinity Corridor, Depth Illusion, Ladder to
Australia, Help Yourself.
Pepper’s Ghost, Swap Heads, Swap Noses,
The Morphing Machine, Morphing Arts Project.
Shadow Play
p.45
Shadow Tracing, Shadow Making, Shadow Wall.
Level D
Pinhole Photography
p.50
2
Making a Pinhole Camera, Demonstrating Why the Image
is Upside Down, The Pinhole Camera, The Camera Obscura.
Lenses Mania
p.55
Light and Colour
p.62
It’s Electric
p.68
Magnifying Objects, The Big (Square) Lens, The Spherical
Lens, Telescopes, Magnifying Instruments.
Pigments and Filters, The Stroop Effect, Colours in the Dark,
Coloured Shadow Wall.
The Plasma Dome, Crackle Ball, Luminglass Plates,
Lightning Tube, Prevention of Accidents.
Appendix
•
•
•
•
How the Eye Works
Perspective in Illusions
‘Mission Target’ focus sheet
Risk assessment
p.74
p.75
p.78
p.89
Introduction
3
Here at Camera Obscura and World of Illusions, we believe that learning
should be fun, exciting and dynamic, just like our exhibits. That is why we
have teamed up with a group of educational specialists to produce a pack
filled with hands-on activities that should encourage pupils to develop a
taste for Science and inspire them for the future.
Together we have reviewed a large amount of material and selected what
we believe to be the best enhancers for an outing to Camera Obscura and
World of Illusions. Much of this material will have appeared elsewhere
but we hope that by condensing the theory and offering step-by-step
activities, we will help reduce a substantial amount of preparatory work
for teachers wishing to visit us.
You will notice that our pack doesn’t always follow a set structure. Our
aim is to suggest the best possible approach to learning by taking into
account the particularities of each of our themes on an individual basis.
Note that all activity sheets can be photocopied or printed out for inclass use.
Most of the exhibits at Camera Obscura and World of Illusions are
hands-on, engaging and highly stimulating. We have tried to reflect this
degree of interaction by providing a great amount of group activities for
the classroom. The main focus of this pack is the study of Science but
you’ll find references to cross-curricular topics such as Art and English
throughout.
This document has been designed to meet the 5-14 Curriculum Guidelines
and, although it is primarily geared at levels C and D, activities should
easily be adaptable for younger or older learners.
We hope that you will enjoy putting this collection of activities into
practice and that we will see you soon at Camera Obscura and World of
Illusions.
Acknowledgements
4
Camera Obscura and World of Illusions would like to thank Jan McLardy
at Careers Scotland who, through ‘Excellence in Education through
Business Links’, has supported this project by teaming our attraction with
a core of teaching professionals:
Mr J Ian Cameron: Trinity Academy
Mrs Valerie Brodie: Woodmuir Primary School
Miss Pamela Docherty: St Columba’s Primary School
Mrs Karen Marie Potter: St Columba’s Primary School
Mrs Eileen Gillespie McLauchlan: Erskine Stewart’s Melville
College
Many thanks to them for having contributed ideas, teaching resources
and written material for this resource pack as well as showing great focus
and enthusiasm towards the project. Thank you also to Bob Kibble,
Science Coordinator at Moray House in Edinburgh for all his support,
direction and input towards this resource pack and David Gray for his
humorous illustrations.
Camera Obscura and World of Illusions
5
The highly acclaimed original ‘multimedia’ attraction, Camera Obscura and
World of Illusions, has been entertaining visitors with its unique
experiences since it first opened in 1853. Located at the top of the Royal
Mile, the tower offers the finest 360 degree city views from its rooftop
terrace and an opportunity to spy on the city through the eye of the giant
Camera Obscura. From this mysterious Victorian rooftop chamber,
visitors of all ages can see live moving images of Edinburgh projected
onto a viewing table through a giant periscope. They can even pick up
people on their hand!
The three floors of fascinating exhibitions include:
• the Magic Gallery packed with illusions and trickery;
• Light Fantastic, displaying the largest collection of
holograms in Britain;
• and Edinburgh Vision where pupils will encounter live and
unique views of the city.
Most exhibits are interactive and the overall effect is captivating for
school children... and adults too! Let yourself be entranced by the giant
kaleidoscopes, amused by the big lenses, intrigued by our optical illusions,
amazed by our infinity wall…
This unique visitor centre is becoming increasingly recognised by teachers
as a valuable source of learning within disciplines such as Science and
Environmental Studies. Every year, a significant number of school
children come through the doors of Camera Obscura and World of
Illusions for a couple of hours of serious fun; a field trip with a vibrant
and colourful twist. Set in the historical Old Town, Camera Obscura and
World of Illusions has the added bonus of being within walking distance
of train and bus stations and it is also close to some of the best
attractions in Scotland.
Visit Planner
6
When can we visit?
We are open 7 days a week (closed on Christmas Day)
April-June: 9.30 to 6.00
July-August: 9.30 to 7.30
September-October: 9.30 to 6.00
November to March: 10.00 to 5.00
The last presentation in the camera obscura is usually one hour before
closing time depending on available daylight.
How much will it cost us?
CURRENT ADMISSION RATES
Normal Rate
Adults
£7.95
Children (5-15)
£5.50
Senior/ Students
£6.50
One leader admitted free of charge for
Group Rate (10 or more)
£6.50
£4.40
£5.50
every ten paying group members.
To benefit from our group rates, you must pre-book at least 24 hours in
advance.
ADMISSION RATES FROM 1 FEBRUARY 2009
Normal Rate
Group Rate (10 or more)
Adults
£8.50
£6.75
Children (5-15)
£5.75
£4.60
Senior/ Students
£6.75
£5.75
One leader admitted free of charge for every ten paying group members.
How can we book?
We recommend that you book your visit as soon as possible to avoid
disappointment. When booking, you will be asked to specify a time of
arrival. On arrival, we will reserve the next available presentation(s) for
your group. Please let us know ahead if you decide to cancel or if you are
delayed.
Where are you located?
7
We are situated at the top of the Royal Mile, just before the Castle and
opposite the Scotch Whisky Experience. Look upwards for an intriguing
black and white dome rising above the skyline of the old town and you will
have found us!
How long will we spend visiting your attraction?
Groups spend on average 1 ½ hours in the building. The presentation in the
Camera is 15 minutes long. You will also find within our tower, three floors
packed with hands-on exhibits and a rooftop terrace perfect for group
photo opportunities. We recommend that you allocate additional time for
our gift-shop as it is a favourite with children and packed with unique
gifts, gadgets and games.
nd
2 floor
Edinburgh Vision
3rd floor
Light Fantastic
4th floor
Magic Gallery
Approximate time per area
20 minutes
10 minutes
20 minutes
5th floor
Rooftop Terrace
5th floor
Camera Obscura
Ground floor
Gift shop
10 minutes
15 minutes
20 minutes
Because of the size of the camera obscura room, groups of 35 or more
will be split into two. At least one teacher must accompany the students
inside the camera obscura.
How can you accommodate wheelchair users?
Please let us know in advance if you think you may require special
assistance on the day. Unfortunately, due to the age of the building,
there is currently no lift. Children using a wheelchair can be carried to
the top of our tower and our staff will be happy to assist you if you wish.
Alternatively, we can supply wheelchair users with an educational
resource pack that can be used on the ground floor in the reception
foyer. The content is representative of the exhibits found in the tower
and should keep students busy for a considerable length of time.
Where can we park our coach?
8
There is metered coach parking nearby on Johnston Terrace.
Alternatively, there is an all day car park at the bottom of Johnston
Terrace at Castle Terrace.
Do you have any toilet facilities?
Our toilet facilities are limited at present, but group members are very
welcome to use them. Alternatively, public toilets can be found at the
very top of the Royal Mile, just before the Castle esplanade, half way
down the stairs on the left. New toilets will be included in the next stage
of our ongoing redevelopment.
How do we contact you for bookings and queries?
Rosalyn Harkness - Bookings and Administration
Phone: 0131 226 3709
Fax: 0131 225 4239
Address: Castlehill, Royal Mile, Edinburgh, EH1 2ND
E-mail address: [email protected]
Website: www.camera-obscura.co.uk
Making the Most of your Visit
9
Before the visit
•
•
•
Our Administrator will have sent you an education pack, including a
risk assessment sheet to help you prepare your pupils for their
visit. A copy of our risk assessment will have also been sent to you.
We ask that you divide any group of 35 people or more into two
smaller groups before your visit. This is due to the limited capacity
in the camera obscura room.
Because of the nature of our establishment, it is easy for a young
audience to be overwhelmed with all there is to do and see. That is
why we encourage you to use our lively ‘Mission Target’ focus
sheets during your visit. This activity will not add a great length of
time to your visit as the questionnaires are relatively short. Pupils
will work in pairs or small groups. Each group will receive one of the
four different Mission Targets on offer. The ‘Mission Target’ work
sheets can be found in appendix for you to photocopy.
On arrival
•
•
•
•
•
To accelerate the admission process and to keep the entrance
passageway clear, weather permitting, we ask that children wait in
the courtyard while your group leader registers at the reception
desk.
You will be given a time for your show(s) in the Camera Obscura on
a ticket. We ask that groups arrive at the top of the stairs (5th
floor) 5 minutes before the allocated starting time.
The receptionist on duty will inform you of the best route to take
on that day. Depending on the size of your group, you may start or
end your visit with the guided tour in the camera obscura.
We would be grateful if at least one teacher could accompany the
groups in the camera obscura room for the 15 minute presentation.
Jackets and school bags can be left in a storage area at the front
desk, although it can get cold and windy out on our outdoor terrace
(5th floor).
10
LEVEL B
AIMS:
STRAND:
•
To experience light and
dark.
Living things and the
processes of Life.
•
To compare
characteristics between
light and dark.
•
To be able to recognise
sources of light.
FACT FILE
Light, either natural or artificial, always travels from a source. Light
also travels in a straight line and in all directions. To see that light, it
must travel to our eyes.
Light bounces off opaque objects. Objects of a darker pigmentation
will absorb some of that light. Smooth and shiny objects like mirrors and
spoons will reflect the light so well that you may be able to yourself in
them.
If an object is transparent, light can travel through it but it can also
bend it. This process of refraction can be demonstrated using a pencil
placed in a clear glass of water. The pencil looks as if it was chopped in
half!
Today, we rely mostly on artificial light to help us in many activities
such as seeing, driving, reading… Power stations provide electricity to
cities while pylons and cables are used to carry electricity from house to
house.
11
Artificial light is something we take for granted. However, 100 years
ago people had to rely on oil, gas and fire to light their houses. Edison’s
light bulb was invented in 1880 but could only stay alight for a few
minutes. Things have evolved and you can now buy energy saving bulbs
lasting up to two years.
On the other hand, it is nowadays very difficult to experience total
darkness as the moon, street lights or a simple light on a digital clock
might interfere. When it’s dark, other senses can be used to find or
identify objects.
Contrary to what many think, the Moon is not itself a source of light.
Light is actually reflected onto the Moon from the Sun and then bounced
back to Earth.
In the classroom
Blindfold Exercise
Group pupils into pairs.
Let them experience total darkness by
blindfolding one pupil per pair. Partners will hand them a variety of preselected objects. Blindfolded children will try to identify these objects
using their senses of touch, smell, hearing or taste. Ask partners to guide
their blindfolded pair on a walk around the classroom. For safety reasons,
partners should give aloud clear directions (right, left, etc.).
Ask:
o What things can you do/not do in the dark?
o How does it feel to be blindfolded?
o How do you think visually impaired people get around on a daily
basis?
Area Walk
Ask pupils to walk around their local area when it’s dark. A parent or older
sibling should accompany them. Can they draw a coloured map of all the
different lights they see? (Street lights, traffic lights, domestic outdoor
lights, shop signs, neon, warning lights, etc.) This exercise should make
them more aware of the vast amount of lights that surround us day and
night. Compare results in class.
12
Ask:
o What are the lights you’ve marked on your map used for?
o Are they all necessary?
o If not, how could they be replaced to save energy?
House Walk
Children should walk around their own house and identify as many lights
as they can. The kitchen is a great place to start. The number of entries
compiled might come as a surprise to many and help pupils be more aware
of how light can help us conduct simple tasks on a day-to-day basis. For
instance, a light on the kettle indicates that the appliance is working, the
light in the fridge helps us to see its contents and a bulb in the television
helps to create the picture. Compare the results in class.
Ask:
o Are all the lights you’ve found really necessary?
o What else could be used as an alternative?
o How do you think people performed domestic chores without all
those electrical lights 100 years ago?
Drawing Night and Day
Distribute a white card and a black card to all the pupils in the class. Ask
them to draw a picture of a house on the white card using coloured
pencils. Using the same exact colours, ask them to repeat the drawing on
the dark card.
Ask:
o How do colours change from light to dark?
o Which drawing is easier to see?
You can try a similar experiment in class by comparing an area of the
room in bright and in dimmed light. You could also take a digital
photograph of the same scene in daylight and at night time and discuss
the differences in class.
Research Projects
□ Do a research project on Edison and the light bulb.
□ Find out how houses were lit 100 years ago.
□ On a local map, mark the location of your nearest power station.
13
At Camera Obscura and World of Illusions
What Colour is Inside the Box? (Magic Gallery)
This activity should reinforce the principle
that dark is the absence of visible light.
Invite pupils to look through the small hole
on the lid of the box.
Ask and do:
o What colour can you see?
o What colour can you actually see
when you open the lid? (The angle of
the lid and the size of the hole make
it difficult for ambient light to
penetrate the box. That is why the
inside appears to be black.)
o Try shining a torch inside the hole.
What do you notice?
Camera Obscura (5th floor)
Inside the camera obscura in Edinburgh
The camera obscura that you will
see was built in 1853 by Maria
Teresa Short, an optician from
Edinburgh. It is the oldest
purpose built attraction in the
city.
Nowadays, technology surrounds
us and we take it for granted.
But back in the 1850’s, the
camera obscura was regarded as
an advanced piece of equipment.
In fact, it was so incredibly fascinating that some people fainted in the
room. Others were convinced it was a form of witchcraft and ran out,
screaming for help. This may seem a bit extreme, but back then, most
people had never seen even a black and white photograph. For them,
seeing a coloured moving image was totally extraordinary.
14
A Bit of History
Camera obscura’ is Latin for ‘dark chamber’. Being inside a camera
obscura chamber is similar to standing inside a giant photographic film
camera, in which the round table takes the place of the film in the
camera where the image is projected.
Camera obscuras have been around for centuries. The ancient Greeks
were familiar with the optical principle and in the 4th century BC,
Aristotle wrote about being able to view a partial eclipse of the sun
projected onto the ground by the narrow shafts of light. From the 13th
century AD astronomers would look at sun spots and solar eclipses with
them.
The Italians experimented with the camera obscura in
the sixteenth century, adding lenses and mirrors to
sharpen the image and adapt it for use as a form of
entertainment with projections inside a room, like an
ancient type of cinema.
The camera obscura was used by artists in the
seventeenth century, and portable camera obscuras
were created including one made in a sedan chair (left),
and tent-like structures. It is thought likely that Vermeer made use of
the camera obscura to create his paintings, utilising its ability to distil
the confused visual information which strikes the eye onto a flat surface.
Our Presentations
We offer three different presentations in the camera obscura. All talks
last for approximately 15 minutes. The talks are as follows:
! Introduction to Edinburgh, perfect for a first visit to the capital
city.
! Light and Dark, ideal to complement your classroom topic.
! Old Town/New Town, for a greater understanding of the evolution
of Scotland’s capital city.
If you would like to have a Light and Dark or Old Town/New Town
presentation on the day of your visit, please inform us ahead so we can
prepare in advance. Otherwise, your presentation will be Introduction to
Edinburgh.
15
How it Works
A camera obscura needs light to create its live image. That is why the
weather plays an important role in its successful operation. The
sunnier it is outside, the brighter the projected picture.
The image is in fact produced by light being reflected from an angled
mirror at the top of a tower and bounced off a white concave dish
inside the room. The room needs to be darkened in order to see the
city come alive.
Lenses are located between the mirror and the dish and that is how
the picture remains sharp and in focus. By rotating the mirror with a
connected handle, a 360 degree panoramic view of Edinburgh can be
obtained. By tilting the mirror up and down, more of the sky or the
ground can be seen.
Around the World
Camera obscuras are found all over the world. Here’s a selection of some
of the most popular.
16
Back in the classroom
Rainbow Making
You can demonstrate how light produces a spectrum of seven colours by
shining a torch through a prism. As indigo is difficult for most people to
see, your pupils may only be able to pick out the six colours they can see:
red, orange, yellow, green, blue and violet. Because the prism is made of
transparent material, light is bent and its trajectory can clearly be
observed by everyone. By placing a second prism on the edge of the
rainbow you have created, you can show how the colours remix into white
light again.
You can also fill a glass with water and carefully place it on a flat surface
near a window. Make sure the sun is shining through the liquid. Position
some white paper on the floor, or window sill, so that the rainbow colours
can be seen.
Alternatively, children can make rainbows at home by simply turning on
the garden hose onto ‘spray’ or ‘fine mist’ mode. The sun should be coming
over their shoulder for this experiment to work.
Research Project
Using school library books or the internet, find out when photography was
invented and who the inventor was. Look at how photos were taken and
developed back then. How is it different from the way we use
photography now? Pay attention to the dark chamber used by
photographers to develop their pictures. (The presence of a bright
source of light would completely ruin the negatives by over-exposing them
to the light.)
If your school has access to old photographs, or prints of old photos
(sepia/black and white), compare them with modern coloured ones.
Compare brightness and sharpness.
Ask:
o Which type do you prefer? Why is that?
o What mood/feeling/emotion does each type of photos convey?
o Looking at the photos, what are the clues that tell you this is
Victorian times? (eg. women wearing long dresses)
17
In class
Worksheet- Light and Dark
Which of these are sources of light?
Gas lamp
Battery
Sun
Spot light
Plug
Fireworks
Lantern
Moon
Mirror
Fire engine
Desk lamp
Fire
The sun is our main source of light but what else does
it produce? H
_____ _____ _____
What can you use to protect the following body parts
from the sun when you go outside?
1- Eyes: _______________
2- Skin: _______________
3- Lips: _______________
4- Head: ______________
Explain how you think people were able to produce light
before the invention of the light bulb.
18
In class
Worksheet- Light and Dark
The Camera Obscura was built in 1853.
Place these items in the order you think they were invented,
number 1 being the oldest.
#____
Internet
#____
#____
#____
Cinema
Television
Photography
#____
Camera Obscura
The picture in the Camera Obscura depends on the weather.
When it’s sunny, the image is ___________________.
When it’s overcast, the picture is ____________________.
When it’s foggy, the picture is ____________________.
Why is the table
painted white?
True or false.
1. We need to be in the dark to see
the Camera Obscura picture.
_______________________
2. At night, the Camera Obscura
picture
is
very
bright.
_______________________
19
3. The Camera Obscura picture can be dull during a heavy
rain storm.
_______________________
LEVEL B
STRAND:
Living things and the
processes of Life.
AIMS:
•
•
•
To show how the eyes
are used to detect
information.
To show how the brain
stores images for a
length of time.
To show how your eyes
can be deceived by
optical toys.
FACT FILE
The human brain is capable of retaining an image for 1/30th of a
second after it has disappeared out of sight.
When a sequence of images is shown very rapidly, for example on a
zoetrope or mutoscope, the brain believes a film is rolling smoothly. This
is because is not capable of keeping those pictures separate, nor can it
quite capture the moments in between pictures when they are flipped
from one to the next.
The brain is in fact too busy storing images that have already
vanished from vision. That physiological phenomenon is known as
‘persistence of vision’ and was first recognised in 1824. Each image
continues to be seen for a split second.
20
When we go to the cinema we don’t realize that the screen is dark
half the time. Because 24 new frames (photos) are shown every second,
the brain retains each and every image long enough for them to merge
and blend in together to create the illusion of movement.
Animated cartoons work using the same principle. To create a
moving picture, artists originally had to draw thousands and thousands of
images, each one slightly different from the other. They would then
rapidly run them together and watch them come alive. Today, computer
programmes are used by cartoonists to facilitate their work.
In the classroom
Flip Book
Resources: white card, colouring pencils, stapler and scissors.
Procedure:
1) If you don’t already have access to small pads of card, your pupils
can cut twenty small rectangular cards of the same size and staple
them together.
2) Ask the children to think of a simple story involving one or two
movements, e.g. a girl blowing up a balloon that then bursts.
3) Invite them to draw that story in a series of simple images slightly
different from one another. These images should be drawn on the
right hand side of each page, away from the spine.
4) To animate the movies, pads will need to be flipped, the quicker,
the better! Pupils can swap them around to compare what others
have done.
Thaumatrope
Resources: white card, colouring pencils, scissors and string.
Procedure:
1) Have pupils cut a disc out of a
sheet of card.
2) Ask them to draw a bird on one
side, flip the circle face down and
draw a cage on the other side. For
21
this illusion to work, you basically
want one drawing right-side up, the
other up-side down.
3) Carefully punch a hole on either side of the disc and attach a piece
of string to each hole.
4) For this illusion to work, the strings have to be held tightly away
from the disc. Ask the children to pull and twist the strings in
order for the disc to be flipped over and over again. By twisting
quickly enough they should see a bird IN a cage as opposed to a
bird AND a cage.
5) Repeat with other designs.
At Camera Obscura and World of Illusions
Zoetrope (Magic Gallery)
How it Works
This is a cylinder with a
series
of
different
pictures on the inside and
viewing slits on the outside.
When you spin it and look
through the slits, it seems
as if the images are moving.
These pictures would have
originally been hand-drawn.
Zoetropes
very
were
popular
Victorian
amusements.
Ask and do:
o Without moving the drum, have a
look at the strip of pictures.
What do you see?
o How many different images can
you count?
o Can you spot the differences
between one image and the next
one?
o Now spin the drum as fast as you
can. Can you describe what’s
happening?
o Spin it the other way. What is the
horse doing?
o Turn the drum one last time, this
time very slowly. How is it
different this time?
o Can you think of other images you
22
could insert inside the drum in
order to obtain more great
animations like the one you’ve just
seen?
The word zoetrope comes from the Greek:
“zoe” means life
and “trope” stands for turn.
The term suggests living wheel or wheel of life.
Praxinoscope (Magic Gallery)
How it Works
A band of pictures, or 3D
objects, is placed around the
edge of a disc. An equal amount
of mirrors is fixed around the
outer surface of an inner drum.
Both face each other.
When the disc rotates, the quick
succession of reflected images
on the drum creates the illusion
of a moving picture show.
By
overcoming
the
image
distortion viewed through small
moving slits, the praxinoscope
eventually
replaced
the
zoetrope.
Ask and do:
o Without
activating
the
praxinoscope, can you count
how many mirrors and figures
there are?
o Can you spot the differences
between
one
figure
and
another? What are they doing?
o Press the button and hold.
What’s happening when the
wheel turns fast/slow?
o How similar/different is this
exhibit to the zoetrope?
o What do the zoetrope and
praxinoscope remind you of?
o Can you think of other objects
you could use to produce a
similar animation?
Being more open, it allows more
light in and because the images
are reflected from a series of
mirrors, the result is much
brighter.
23
Mutoscope (Magic Gallery)
How it Works
The mutoscope works just like a flip-book. A sequence of
photos (600 in this case) is positioned around a cylinder
and linked to a handle. When the handle is turned, the
photos flip to create the illusion of movement.
Provocative themes were very much in fashion in the late
19th century and women were often seen undressing.
Mutoscope movies offended morals but still remained a
very popular form of amusement.
LEVEL B
STRAND:
Living things and the
processes of Life.
AIMS:
• To initiate the concept
of 3-dimensions
• To show that each eye
sees a slight different
image
• To experience a variety
of 3-D images
FACT FILE
Your eyes are set slightly apart and each registers a different but
similar viewpoint. Each eye is looking at the same view but because the
angles are different, two different images are sent to the brain.
24
These images are then combined and, as a result, we get a threedimensional representation of the world we see. This process is known as
stereovision. Not only do we see the world from left to right and up and
down but we also perceive objects with depth (forwards and backwards).
As a result, we are able to judge distances between objects. We are
gifted with what is called depth of perception.
If you injure one of your eyes, your depth of perception is affected.
You can still see the shape and the position in space of most objects
around you but distances are much harder to negotiate. That is why
people with such a medical condition are told not to drive.
This visual ability is also known in primates. That is how they can
evaluate the position of branches in order to grasp them and jump safely
from tree to tree.
In the classroom
Binocular Stereovision
Here are a range of exercises demonstrating how we need our two eyes
to work together as a team.
# Cover one eye with your hand and look at an object on the wall. Now
change and cover your other eye. What do you notice? What is
happening? Is the object jumping from one side to the other? You
can also do this exercise by holding a finger in front of your nose
and closing one eye at a time.
# To spice things up, try catching a ball with only one eye open. For
safety reasons, we recommend that you try this outside. You can
also try reaching out to shake someone’s hand with one eye shut. Do
you see an improvement when you open both eyes?
# Roll up a sheet of paper into a tube. The diameter should be around
5cm. With your right hand, hold the tube against your right eye.
Now put your left hand next to the tube, half way down the middle.
The inside of your left hand should be facing you. Stare down the
tube for 20 seconds or so. Do you see the hole in your hand? That
25
is because your brain has merged two images (hole and hand) into
one.
A bit of Fun…
Hold the drawing below in front of you and stare at the space between
the fish and the tank. By slowly moving the drawing towards you, the
fish will seem to be inside the tank.
At the Camera Obscura and World of Illusions
Stereoscopes/3D Viewers (Edinburgh Vision)
How it Works
The stereoscope uses two photographs
taken at slightly different angles to
adjust to both eyes and create a
depth illusion. The brain then merges
both images and the result is one of
distance and solidity. The objects are
seen in relief.
This optical toy was popular in the late
19th century. Viewmasters can still be
found in some shops and are the
contemporary version of this Victorian
amusement. The coloured 3D Viewers
in Edinburgh Vision work on the same
principle.
Ask and do:
o Have a look at some of
the 3D stereoscopic
images
in
the
exhibitions. Which ones
do you like best? Why
is that?
o Now cover your left
eye with your hand and
look at the same images
through the lenses. Try
covering your right eye
instead and repeat the
experiment.
o How different are the
pictures now? Are they
still in 3D when you
look at them with one
26
eye only?
o What is the best way
to see these images in
depth?
o Out of the coloured
and black and white
stereoscopic
photos,
which ones are the
easiest to see in 3D?
Anaglyph (Edinburgh Vision)
Ask and do:
o Have a look at the anaglyph on display with the special glasses
hanging on the wall. Make sure that the red lens is over your left
eye. Describe what you see to a friend.
o Now remove the glasses and look at the picture again. Is the picture
easier to see without the glasses? What colours can you see on the
actual print?
o Try looking at the picture
once more, this time with the
red filter over your right
eye. What do you see?
o Where
have
you
seen
pictures like this before?
27
How it Works
This type of depth illusion is derived from the stereoscope and was
first shown to an audience in the 1850’s. This time it is created by
superimposing the shades of red and blue (or green) from two 2D
pictures taken 2.5 inches apart, the average distance between the
human eyes.
To view an image in 3D, you have to use red and blue (or green) lenses.
The red lens (left eye) filters out the red in the image in order for you
to see the blue picture and vice-versa.
This type of special effect is popular in advertising and has been used
many times in children’s magazines. The movies Spy Kids 3D and Shrek
3D were made using the same technique. Audiences watched the film
with special colour glasses.
Holograms (Light Fantastic)
28
How it Works
A holographic image is made by splitting
a laser into two different beams. One
beam of light hits an object. The image
of that object is then caught on film
whilst the other beam is projected
directly onto that same film. By doing
so, the two beams of light form a
particular pattern on the film and that
is how the object appears 3 dimensional.
Our holograms are best viewed at about 5
feet off the ground. Children should be
encouraged to step up onto stools or move
around each exhibit.
Ask and do:
o In small groups, go
round the gallery and
look closely at all the
holograms on display.
There are different
types
of
images.
Some
holograms
appear to be moving.
Some are still. Can
you find one image of
each type?
o Find the Microscope
hologram. By standing
up on a stool far
enough
from
the
picture, you should
be able to look
through the eyepiece
coming at you. What
can you see? (A
micro-chip.)
o Locate
the
Gun
hologram.
Look
through the barrel.
What do you see?
(An eye.)
29
Mirror 3D (Edinburgh Vision)
How it Works
To create a 3D mirror effect, two incredibly
similar pictures are taken of a same still scene.
One picture is flipped left to right when
developed. The original picture is positioned on
the right hand side of a 90 degree angled
structure; the flipped one, on the left.
Graphic taken from www.cs.technion.ac.il
To view the scene in stereoscopic vision, step on
the footprints, put your nose against the edge of
the mirror and face the image in front of you
(the right sided one). That way, your right eye
sees the image on the right; your left eye sees
the left image, through a mirrored reflection
this time. Each eye is now seeing the same view,
but through two different pictures. That is why
the image is in 3D.
Ask and do:
o Have a look at all the Mirror 3D pictures on display. Some are in
colour, others in black and white. Which type do you find more
effective? Explain your answer.
o What do you think a person with one eye only would see? You can
discuss the issue back in the classroom, or even research it as a
project.
Telescopic Peepshow of the Great Exhibition of 1851
(Edinburgh Vision)
Peepshows first became popular in the eighteenth century. Between card
covers a series of receding scenes in mounted on concertina-folded strips
of cloth or paper. A spy hole in the front cover allows you to see a deep
3D perspective when the bellows are fully extended. Looking through this
old optical toy feels like going back in time…
30
On site
Worksheet- Holograms
There are lots of holograms on display on the third floor of Camera
Obscura and World of Illusions.
Which one is your favourite?
………………………………………………………………………………………………………………………………………
Why do you like this one?
………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………
………………………………………………………………………………………………………………………………………
What are the differences between a photograph and a hologram?
Photograph
Hologram
A hologram is special because…
A photograph is special because…
You’ll need a partner for this
activity.
One of you close your eyes. The
other one describes a hologramone that is in the room.
Then the person who wasn’t looking
has to point out the hologram you
described.
HOLOGRAMS
Look closely at the word
‘holograms’.
Using different letter
combinations, how many new
words can you form?
12…
logs
3- change and do the task again.
Now
4Who was the better explainer?
Which words did you use?
31
LEVEL C
STRAND:
Properties and uses of
energy.
AIMS:
• To
develop
an
understanding of energy
through the study of
the properties and uses
of light.
• To
experience
light
being reflected from a
range of surfaces.
• To design and make a
kaleidoscope.
FACT FILE
A kaleidoscope is a tube made up of mirrors that contains loose
coloured objects at one end that are reflected off the mirrors as light
enters the tube.
To maximise the impact, a strong source of light should be placed
behind the cell of objects. These objects produce changing symmetrical
patterns when the tube is rotated.
The other end of the tube is kept open and this is where the viewer
looks in.
The 3-mirror system is the most popular design of all kaleidoscopes,
creating continuous reflecting patterns.
The invention of the kaleidoscope is attributed to a Scot, Sir David
Brewster who patented this highly popular Victorian amusement in 1816.
32
In the classroom
2 Mirror Reflections
A simple way to introduce
children to the magic of
kaleidoscopes is to place
an object between two
mirrors set at a slight
angle. Their reflective
sides should be facing
each other.
Various
reflective patterns can
be formed by bringing
the mirrors closer or
further from each other.
The angle at which the two mirrors are positioned determines the number
of reflections that can be seen. Experiment in class with objects of
different shapes and colours.
Ask:
o How many times is your chosen object reflected in the mirrors?
o Change the angle. How different is the reflection this time? Can
you count as many objects as before?
o Are all the reflected objects in the mirrors facing the same way?
Describe the pattern you see in the mirrors.
o Write the letter ‘B’ on a small piece of paper, place it between the
mirrors and look at the reflection produced. What do you notice?
o Write your name down and place it between the mirrors. Can you
still read it by looking in the mirrors?
Making a Kaleidoscope
Resources: three mirrors of the same size clear acetate, hundreds and
thousands, sticky tape, scissors. Divide the class into small groups.
Procedure:
1) Tape three mirrors together with their reflective side facing
inwards, to make a triangular prism.
2) Cut out two triangles from the acetate and place them on top of
one another and tape two of the three sides together. You should
now have a cell with an opening.
33
3) Cut out two triangles from the acetate and place them on top of
one another and tape two of the three sides together. You should
now have a cell with an opening.
4) Through the opening, carefully sprinkle hundreds and thousands (or
equivalent) and seal with tape. The sweets should be able to move
within the cell.
5) Fix the cell to one end of the triangular prism with sticky tape.
6) Now hold your kaleidoscope up to the light and turn it with your
hand to make a pattern.
7) By removing the cell altogether, you can also create a different
kaleidoscope. Whatever you are pointing at the time becomes the
image in the scope.
At Camera Obscura and World of Illusions
Giant Kaleidoscope (foyer)
Ask and do:
o What is the first thing that
you see? (a sphere)
o How many mirrored sides can
you count?
o Are they the same size
throughout?
(They
are
narrower at the far end.
That is why you see a ball.)
o Why do you think the patterns on that sphere change?
34
o What happens if you wave your hand inside the kaleidoscope?
o What else can you see? (Fibre optic lights.)
o How many times can you see yourself?
Large Kaleidoscope (Magic Gallery)
Ask and do:
o What is the first thing
that you see?
o Why is this sphere smaller
than the one you saw in the
foyer?
(Because
this
kaleidoscope has smaller
mirrors and a smaller
image.)
o How different is this
kaleidoscope from the one
in the foyer?
Fibre Optic Kaleidoscope (Magic Gallery)
Ask and do:
o How many mirrors can you count?
(Three this time.)
o Can you see the computer screen?
(There is none. It has been replaced
by animated fibre optic lights.)
o What else is different about this
kaleidoscope? (There is a glass
frontage and you can also see the
tube’s triangular shape.)
Kaleidosphere (top floor, indoors)
The kaleidosphere is a portable exhibit. It can usually be found on top of
the cupboard between the windows and the camera obscura door. Feel
free to take it outside.
Look through the larger end of the kaleidosphere. Start with the narrow
end pointed towards the ground, and then slowly lift upwards. Small
metallic spheres come rolling at you for a dramatic effect. The views are
much sharper when you point the kaleidosphere towards the sky. Try
pointing at different colours and textures for varied effects.
35
LEVEL C
STRAND:
Properties and uses of
energy.
AIMS:
• To
consolidate
the
concept of reflection.
• To
give
pupils
an
experience
involving
light reflected from a
range of surfaces.
• To explain the concept
of concave and convex
mirrors.
FACT FILE
Light travels in a straight line. That is why you can see an identical
image of yourself when you are looking in a flat mirror. In fact, what you
are seeing is a reflection of yourself.
A reflection occurs when light rays bounce off objects and into our
eyes.
For a reflection to occur, you need a light source such as the Sun or a
light bulb. You also need a reflective surface such as a mirror or glass.
Sometimes, light reflected from certain objects can have interesting
results. Bendy mirrors are a classic example of how images can be
distorted.
Convex mirrors bend out and will stretch you and make you appear
taller.
36
Concave mirrors bend in and will squish you and make you appear
shorter.
In the classroom
Exploring Mirrors
Resources: a selection of mirrors: flat mirror, magnifying, shaving or
make-up mirror, rear-view mirror, rectangular bendy mirror sheet,
kitchen paper foil, teaspoons, Perspex glass, coloured card. Divide the
class into small groups.
Procedure:
1) Give the children the experience of using a flat mirror. This will
allow them to understand that a flat mirror does not distort or
alter an image.
2) The complete opposite happens when they look into the back of a
spoon. Try rounder spoons, oval spoons, etc.
3) Give the children a selection of mirrors. Allow them to explore
different images. What do they notice? Some mirrors magnify,
some make images appear further away.
4) Invite pupils to spot their reflection
in a window or a large piece of
Perspex glass. Try adding different
things behind the glass like a white
sheet, a coloured card or a
blackboard. Which colour works
best? Place the kitchen foil behind
the clear glass (or window). You now
have a mirror.
5) Ask children to hold the bendy mirror sheet vertically and curve it
inwards, then backwards. What happens? Repeat with the mirror
turned horizontally this time.
Mirror Drawing
Draw a red star on a piece of paper. Hold a small mirror upwards, behind
the paper, so that you can see the star in it. Now try drawing over the
star, with a blue pencil this time. For this experiment to work, you MUST
be looking into the mirror at all times while tracing, NOT at the paper.
37
To complicate things, take a new
sheet of paper and place the
mirror behind it again. This time,
try writing your name on the
paper. Remember to keeping
looking into the mirror as you do
this. Why is it so difficult? (When
you look into the mirror, the top
of the sketch becomes the
bottom.)
At Camera Obscura and World of Illusions
Bendy Mirrors (Magic Gallery)
Ask and do:
o Can you point out the convex/concave bends or folds on the bendy
mirrors? Describe what is happening to your reflection.
o Try moving your arms and legs very slowly as if someone from
above was slowly stretching you like a playdough character.
o How about opening your mouth as
wide as you can. Which mirror will
give you the illusion of a lion’s
roar?
o Can you spot the slimming mirror?
Why is it slimming?
o Which mirror is your favourite?
Why? How does it make you feel?
o With a digital camera,
try taking photographs
of these images which
can later be displayed in
class.
o Draw a picture of one
of your friends standing
in front of a bendy
mirror.
38
Shake Hands (Magic Gallery)
Ask and do:
o What makes you think this is a
concave mirror?
o Is the reflection of your hand smaller
or bigger? Does it change in size if
you move closer or further away from
the mirror?
o Shake hands with your ghosts and
reach for their ghost’s hand.
o Try it with an object. A pen joined to
its reflection will give you the illusion
of a giant pen.
Infinity Corridor (Edinburgh Vision)
How it Works
If you look carefully, you will see tiny
fibre optic lights mounted on a
mirrored wall behind the glass
surface they are fronting.
Because the inside of the glass panel
is reflective, light gets trapped
between glass and mirror and is
bounced back and forth between the
two. That is why you can see layers
upon layers of magical lights
disappearing into infinity.
The large mirror wall behind you
gives an illusion of space to the
corridor and does not affect how
light is reflected inside the case.
Ask and do:
o What is the light source
used in this type of
reflection?
o What are the reflective
surfaces?
o Why do you think lights
curve and fade away at a
distance? (Because the
intensity
of
light
is
reduced each time it is
bounced off between glass
and mirror.)
o Take a torch and shine it
on your face while facing
the infinity wall. What do
you see on the glass panel
you are facing?
o Stare at the twinkling lights for
a while. You have the sensation
of being in space.
39
Depth Illusion and Ladder to Australia (Magic Gallery)
How it Works
These two similar exhibits bounce
reflections into infinity, just like the
Infinity Corridor does. The width
between the glass panel on the outside
and the mirror on the inside of each
exhibit is surprisingly small.
Because both of these materials are
reflective, the image jumps time and
time again between the two. The
reason why this image fades away in
the distance is that a little light is lost
from each reflection.
Ask and do:
o Look
at
these
two
illusions. Count how many
rings/ ladder rungs there
are.
o Locate the
reflective
surfaces used for these
types of illusions? What is
the approximate distance
between the inside mirror
and the glass panel?
o Name the light sources
that are used to illuminate
those
two
illusions?
Where are they located?
o Why do you think one of
the exhibits is called
Ladder to Australia?
o Have you ever seen
anything similar to the
Depth Illusion?
(An underground tunnel.)
Help yourself (Light Fantastic)
How it Works
Ask and do:
o Can you grab the
sweets and run your
fingers through them?
o What happens when you
look directly above the
aperture?
This mirage is created from two
concealed
parabolic
mirrors,
opposite each other. A small object
is placed on the concave centre of
the mirrored dome and instantly, an
image projects up in the air. You can
see the hologram when you move
around the dome.
40
In class
Worksheet- Hall of Mirrors
Look into a mirror of your choice. Can you see the back
of your head? Why not? How can you achieve this?
…………………………………………………………………
……………………….…………………………………………
……………………………………………….…………………
…………………………………………………………………
…………………………………………………………………………………………..
…………………………………………………………………………………………..
Fill in the gaps using the following words:
concave, convex, outwards, inwards
A concave mirror curves ........................ and produces a …………………… image.
A convex mirror curves ……………… and produces a …………………… image.
True or false
o A flat or plain mirror distorts an image. …………
o Light is required to produce a reflection. …………
o Glass is a reflective material. …………
o Wood is a reflective material. …………
Which object belongs to which reflection? Link the objects on the left to
the correct answer box on the right by linking the two with an arrow.
The glass of a window
A shoe
A watch face
A teaspoon
A mirror
My friend’s eye
A key
A wooden pencil
No reflection to be seen
Some degree of reflection
Clear, sharp reflection
41
LEVEL C
STRAND:
Properties and uses of
energy.
AIMS:
• To further develop the
concept of reflection.
• To demonstrate how
glass can affect the
way
in
which
light
travels.
• To initiate pupils to the
morphing process
FACT FILE
For a reflection to occur, you need a reflective surface and a light
source. But it is not only mirrors that can reflect your image.
Sometimes you look into a shop window and although you can see
what’s behind the window, you can also see your own reflection. This
process of image superposition is called a ‘Pepper’s Ghost’ and dates from
the 19th century.
What is happening is that part of the light is transmitted and part of
it is reflected. In other words, some degree of light goes through the
glass and some of it is bounced back out again.
For this to happen, the intensity or amount of light and the degree
of reflection (shininess) need to be the same on both sides of a clear
surface. They are competing against one and another.
The following activities show how two faces can morph into one.
42
In the classroom
Pepper’s Ghost
Resources: Perspex sheets, torches, a dark room. Pupils should work in
pairs.
Procedure:
1) Distribute a piece of
Perspex and a torch to
each pair.
2) Pairs should face each
other and hold the
Perspex sheet between
them. One pupil holds
the torch and shines it
on his face. What’s
happening? Who can be
seen
on
the
shiny
surface?
3) Pupils can then shine the torch on their partner’s face instead. How
different is the result?
4) Swap the torch over with your partner and repeat the process.
Swap partners for different amusing results.
5) Explain that light from the torch reflects from your face. Some of
it travels straight through the glass to allow the other person to
see you. The remaining light will bounce back off the glass to allow
you to see yourself.
6) Invite the children to try this at home with their parents. They can
use a window in a dark room.
Who was Pepper? (Late 19th century)
He was a Chemistry Professor from London who developed a way to
create ghostly effects for theatres by positioning a transparent window
at an angle to the audience.
This technique meant that spooky reflections of off-stage actors could
be projected, whilst one-stage actors could walk right through them with
mind-blowing effects.
43
At Camera Obscura and World of Illusions
Swap Heads (Magic Gallery)
In pairs, invite the children to
repeat the experiments they have
tried in the classroom. One at a
time, the children can rotate the
knob on the table in front of them.
By doing so, they are lowering the
intensity of light on one side and
raising it on the other.
The brighter it is on their side, the more reflective the picture becomes.
But by adjusting the light to an equal level on both sides, they will slowly
morph into their friend.
Ask and do:
o Do you notice any differences between this experiment and the one
you tried in class?
o Describe what you see to your partner. How do you like your new
look?
o What is the panel made of? List its properties.
o Where are the lights located?
o Where are you most likely to see this trick? (In films like Harry
Potter.)
o Who would you love to be morphed into?
Swap Noses (Magic Gallery)
Ask the children to sit across from a friend. Their faces need to be
directly opposite each other for this illusion to work.
Ask and do:
o Who can you see? What do you think of your new nose?
o Can you describe your new facial features to the group?
o What’s the panel situated between the two of you made of? Is it a
mirror or a piece of glass? (It is in fact a combination of
alternating mirrored and glass strips. That is why you see a mixture
of yourself and your partner’s face.)
o What would you see if the strips were larger/thinner?
44
The Morphing Machine (Edinburgh Vision)
Because
children
have to wait in turn
to use the Morphing
Machine,
we
recommend that you
only
invite
4-5
children at a time to
join the queue.
How it Works
This form of trickery is rather modern in
comparison to the Pepper’s Ghost. This
time, it involves the use of a computer, a
web camera and a specific computer
programme. The computer takes a photo of
your face, you then select the character
you’d like to be morphed into and the rest
is pure fun and games!
During busy periods,
limit their morphing
experience to one
character each. To
maximise your time,
let the remaining
students explore the
other
different
parts of Edinburgh
Vision.
Back in the classroom
Morphing Arts Project
For this, you will need two sheets of acetate and a felt pen. Start by
tracing an egg shape on the first acetate. By placing the second acetate
over this one, trace an identical egg shape. You now have two basic face
contours.
Be creative and draw distinctive facial features on the two egg shapes.
Once the two drawings are complete, put them on top of each other and
admire the result. The pictures on the acetates can be erased with water
and drawn over again. Swap faces with friends for a variety of effects.
45
LEVEL C
STRAND:
Properties and uses of
energy.
AIMS:
• To
develop
an
understanding
of
shadow formations.
• To record position and
motion of shadows over
time.
• To
identify
how
shadows
can
be
manipulated
using
independent variables.
FACT FILE
For shadows to come alive, three variables are needed: a light
source, an object to block that light and a surface onto which shadows
can form.
All objects create shadows, whether they are opaque, translucent or
transparent.
Shadows vary in size and may look like the objects that make them.
However, depending on the position of the light source and the distance
between that light, the object and the surface, they can look bigger or
smaller.
Shadows are shorter before mid-day, then longer until they
disappear as the Sun sets. The Sun doesn’t cast a shadow when positioned
directly above objects. That is why there are no shadows at mid-day,
when the Sun is at its highest.
46
Light needs to shine behind you for your shadow to appear in front
of you. Likewise, if the source of light is to your left, your shadow will
appear on your right.
In the classroom
Shadow Tracing
Resources: chalk, flat school grounds. Students should work in pairs.
Procedure:
1) Pairs of pupils spread out over the
playground. One pupil is the model,
the other the artist.
2) 10.00a.m. (variable). Artists should
use chalk to trace the outline of their
partners’ shadow. For best results,
models should have their back to the
sun.
3) To determine exactly where models were standing at the time of
tracing, artists should also draw around their partner’s shoes, and
then label the tracing for easy identification. How similar/
different is your shadow to you? Is it bigger or smaller? Have the
models lying on the ground, in their shadow to compare sizes.
4) Invite all models to stand on the same spot
and move in closer and farther from their
shadow. What happens? (The image will be
shorter depending on the angle of the light
hitting the object.) Can you identify and
position the light source? How can we make
the shadows larger and smaller?
5) Go back outside at 12 noon and then again two hours later. Ask the
models to step back onto the outline of their shoes and their
partners to repeat tracing. Where are the shadows now? Why have
the shadows moved? How different in shape and length are the new
shadows? How is the time of day affecting the shadows?
6) For a real challenge, ask all the pupils to trace around their own
shadow. Why is this an impossible task?
7) Ask the students to stand in the shade of a tree. Why can’t they
see their own shadow?
47
Shadow Making
Resources: a large white sheet, a large torch or projector, coloured
cellophane filters.
Procedure:
In a dark room, ask two volunteers to hold the sheet in order to form a
giant screen. Get another class member to stand a few metres behind the
sheet, shining a torch onto it.
1) One at a time, pupils will position themselves between the torch
and the screen. Essentially, the torch should be shining behind
them. Pupils will be given various different challenges.
2) Can they make their shadow grow larger and smaller? How can
they achieve this? Get them to predict the size of the shadows
if people stand very close to the torch, halfway between the
torch and the screen and very close to the screen. Test their
prediction. Ask them to describe the differences they see.
3) How can they change the shape of their shadow? Ask one pupil
to stand still, halfway between the torch and the sheet. Let
others experiment with the angle of the torch. Get them to
predict what the shadow will look like when the torch is shone
directly above the person, to their right, to their left, slightly
lower, etc. Test your predictions. How clear or fuzzy are each
of these shadows?
4) Why not combine angles and distances. How many different
shadows can they form?
5) What happens to the shadows when they cover the torch with a
coloured filter? Does it affecting the quality of the shadows?
48
At Camera Obscura and World of Illusions
Shadow Wall (Magic Gallery)
How it Works
The screen you see is
coated with a photoluminescent
substance
called phosphor which
absorbs the light from
the flash and stores it
for a short while.
By standing in front of
the screen, the shape of
the body blocks that
light. The stored light
then shines as a green
glow, except in the area
of the shadow.
Phosphors are also found
on glow in the dark toys
such as stars.
You can demonstrate this
in class by blocking a
section
of
a
phosphorescent star with
your thumb whilst you
are shining a torch at it.
Only the exposed part
will be luminescent.
Ask a few pupils at a time to stand in
front of the Shadow Wall and pose
in amusing ways. Press the button on
the wall to activate the flash. This
will take a few seconds. Have the
children move away from the screen.
They will see a shadow of themselves
appearing on the wall.
Ask and do:
o How do you think this is
happening?
o Where is the light source?
o Why are these shadows not
following you?
o In which position will you have to
stand to see a profile shadow of
yourself?
o Instead of standing still, move
your arms rapidly in front of the
screen as the flash is being
activated. Describe the quality of
shadow you can now see.
o How far away from the wall can
you stand before being unable to
see your shadow against the wall?
49
In class
Worksheet- Shadow Play
Malcolm draws a chalk line around Mary’s shadow. It is 10.am. South is
behind Mary. It is also where the school is situated.
On this sketch, show where you think Mary’s shadow will be at noon.
Late in the afternoon, the sun will set over the school. Draw Mary’s
shadow at sunset.
How could you make a shadow clock in your school playground?
First…
Next…
And finally…
50
LEVEL D
STRAND:
Energy and Forces.
AIMS:
• To demonstrate how
light
travels
in
a
straight line.
• To show how the image
is formed in a pinhole
camera.
•
To explain why the
image is upside down.
FACT FILE
The camera obscura is the most ancient design of all cameras and it
dates from as early as the 4th century BC. Sadly, no one person can claim
to have invented it, as it evolved from an observed natural phenomenon.
For this spectacle to happen, light needs to pass through a small
hole in a dark space. Because light travels in a straight line, it produces an
upside down image of an exterior scene. The image is projected onto a
surface inside the dark space. Just like rays of light passing through an
opening of dense foliage, this reproduces an image of the sun on the
ground.
Camera obscuras were great Victorian amusements and came in
different shapes and sizes. Many artists used them to trace scenes that
they would paint in afterwards. This form of capturing real-life led to
photography as we know it today.
Camera obscuras like the one you will visit in Edinburgh can still be
found all around the world. Even today, the selection and isolation of the
projected image is seen as a magical experience.
51
In the classroom
Making a Pinhole Camera
Resources: drink carton, masking tape, tracing paper, scissors, pin, kebab
stick, modelling knife, letter template (T, F or Y), white board, and overhead projector. The class should split into groups.
Procedure:
Cutting the square aperture in the back of the carton can be done with
scissors but an adult should be performing the initial incision with the
modelling knife. The letter template should also be cut in advance by the
teacher using a piece of white board.
1) Ask the pupils to cut a square of about 6cm by 6cm in the back of a
drink carton.
2) They will then place a piece of tracing paper over the hole and tape
it around the edges.
52
3) A pin can be used to make a hole in the centre of the opposite side
of the box. The pinhole will be too small so it can be enlarged with
a skewer.
4) Teachers, lay your letter template on top of the projector so you
see a nice, bright shape.
5) Now invite the students to hold their camera and point the pinhole
at the template lying on the surface of the projector.
6) Have them look at the screen in the way you do when using a digital
camera. On the screen, they should see an upside down image of
the letter template.
7) Try making the pinhole bigger and bigger again. This will make the
image brighter, but more blurry. To make the picture clear again,
you could fix a lens through the pinhole.
8) Explain that you could fix the image using photo-sensitive paper
inside the box, in front of the screen. With the right material, you
could even develop your photos.
Demonstrating Why the Image is Upside Down
Resources: five 2cm pre-cut coloured cardboard squares, blue tack, white
board, template. Demonstrate this to the whole class.
Procedure:
1) Transfer the template onto the whiteboard. Arrange the squares
to make the pattern T on the left hand side, opposite the camera
illustration.
2) Explain that light travels in a straight line through the pinhole and
is projected onto the paper screen.
3) On your diagram, take the bottom square of your T figure on the
left and slide it along the traced line to show that it will end up at
the top, on the right.
4) Slide the remaining four squares to complete the image.
53
At Camera Obscura and World of Illusions
The Pinhole Camera (Edinburgh Vision)
Encourage one member of the class to stand next to the wall outside the
giant pinhole (in front of the large illustration). Other pupils can step
inside the booth and look through the small hole using a lens of their
choice.
Ask and do:
o Why is your friend upside down?
o What happens when you look through the pinhole with/ without the
different lenses?
o Why is the illustration on the wall the right way up when you look
at it from the pinhole box?
Ask pupils to name 5 containers that can be used as pinhole cameras.
They can look around the room for clues. They will also see on the walls a
collection of photographs taken with pinhole cameras. How are these
photos different from the ones we are used to seeing in our everyday
life?
54
The Camera Obscura (top floor)
How it Works
The Camera Obscura in
Edinburgh was built in
1853 and designed by an
optician named Maria
Short.
On top of the tower
outside, a flat mirror is
set at an angle and
reflects the light from
outside onto a white
concave table inside a
darkened room.
You might be coming to the Camera
Obscura to complement a Science,
Geography or a History lesson. To
enhance your visit, please inform us in
advance if you want your pupils to hear
one of our 3 adapted shows. The
presentations last 15 minutes and
participation is encouraged.
(See the chapter on Light and Dark for
more details.)
By turning the pole, the
guide rotates the mirror
to project a panoramic
view of the city; by tilting
it up or down, more views
of the sky or of the
ground appear on the
table.
55
LEVEL D
STRAND:
Energy and Forces (light and
sound/action of lenses).
AIMS:
• To
explain
the
relationship
between
light and lenses.
• To show that a lens can
form an image in two
ways.
•
To explain that in a
telescope the lenses
combine to produce the
final image.
FACT FILE
Most lenses are shaped like lentils. They bend light to magnify or
focus it.
When rays of light pass through a lens they bend inward and meet
to form an image. When you look at an object close to the lens, it
produces a magnified image. This is called a Virtual Image; it seems to be
there but it isn’t really (like virtual reality).
When you look at an object far away from the lens however, it
produces a smaller image; this time upside down and suspended into space.
This is called a Real Image.
The big (square) lens that you see in the Magic Gallery is called a
Fresnel lens. It is made of many grooves shaped differently in order to
refract or bend light in the same way that a lentil shaped lens does, but
without the bulk effect. That is why it is very powerful, yet very slim.
56
This type of lens was invented by Augustus Fresnel for use in
lighthouses. These days, you find Fresnel lenses in car headlights, stage
lights and in overhead projectors (under the glass where the acetate is
placed).
In the classroom
Magnifying Objects
Resources: magnifying glasses, small objects (e.g. coin, pin, dead insect,
leaf, feather, hair, shoelace, earring), measuring tapes or rulers,
worksheet. The class should be divided into pairs.
Procedure:
1) Spread the small objects into several stations around the room.
Make sure they are all lying on a flat, neutral surface.
2) Give a magnifying glass and a measuring tape/ruler to each pair.
3) Ask children to look at all the small objects from three different
distances: 5cm, 20cm, and 45cm.
4) For each of the viewings, the students should determine whether
the result is clear or blurred. They can also identify the best
distance to view the objects. It may be a totally new distance e.g.
17cm.
5) When you move all back together, discuss your findings. Which
objects were easiest/ hardest to see and why? Did the size of the
different objects viewed have an effect on the results? What else
can we use to enlarge an image?
6) Stress that human vision has its limitations. Invite pupils wearing
glasses to pass them carefully around so that others can
experience different focal lengths. Ask them why they think it is
difficult to see when you are wearing someone else’s glasses?
57
At Camera Obscura and World of Illusions
The Big Lenses (Magic Gallery)
For this exercise, split pairs up on either
side of the lenses.
Ask and do:
o Is the image you see the right way up
or upside down? What else can you
observe? (The lenses enlarge.)
o Can you predict what would happen if
both of you were to move away from
the lenses? Check your answer by
slowly walking backwards, both still
facing your lens. What is happening
to the magnified image when you
move further away from each other?
o Slowly move forward, this time as close as you can get to your lens.
At what distance does it become impossible for you to see your
partner’s face in the lens? Why is this?
o Feel the shape of your big lens. Is it round or flat? Can you see the
grooves inside the lens?
o Can you think of a similar type of lens you might use on a daily
basis? (A magnifying reading glass.)
How it Works
These intriguing Fresnel lenses
are Plano-concave. They have one
flat surface (plano) and an inward
curved one (concave).
They give the impression of
enlarging a virtual image on one
side, as well as spreading the light
on the opposite side.
58
Telescopes (Rooftop Terrace)
Two of the four telescopes you will find at our attraction are amongst the
most powerful in Britain. Three of them are binocular which means that
they are made for both eyes. The last telescope is monocular and used
with one eye at a time. Here is a brief description of them all.
Chinese telescope (silver): binocular, 25 X magnification meaning
that objects can appear up to 25 times bigger than they actually are.
Russian telescope (white): binocular, 20 X magnification but it allows
more light in than the Chinese one because its objective lenses are larger.
Japanese telescope (large
black):
binocular,
8
X
magnification
German telescope (slim
black):
monocular,
10
X
magnification
How it Works
A telescope uses two main lenses.
The front lens is called the
objective lens. It collects light from
a distant object and forms an image.
The second lens is known as the
eyepiece and it magnifies (enlarges)
the image formed by the objective.
In telescopes designed for land use,
the image isn’t upside down because
a third lens is used to flip the image
the right way up. On the other hand,
astronomical telescopes leave the
image upside down and do not
require the third lens.
Ask and do:
o If time permits, take
turns at looking through all
four telescopes on the
rooftop terrace.
o What differences do you
notice between them?
(shape, size, monocular,
binocular, etc.)
o Can you describe three
buildings you see through
the telescopes? Where
are they located? What
type of telescope are you
using?
Use
the
worksheet
provided to collect this
information.
59
Back in the classroom
Magnifying Instruments
Divide your pupils into small groups and ask them to list as many
magnifying instruments as they can. Invite them to use the school library
and the Internet to help them with their search.
Using a microscope, ask the students to look at things difficult to see
with the naked eye such as hair, dust particles, small insects, etc. They
should them attempt to draw what they see as accurately as possible and
share their findings with the group.
60
In class
Worksheet- Magnifying Objects
o Stop at each station to look at the selected objects with a
magnifying glass.
o Measure a 5cm distance between your object and your
magnifying glass.
o Note in the grid below if what you see is clear or blurred.
o Repeat this exercise at 20cm and 45cm.
o Finally, note down the distance your objects are best viewed at.
It can be a new distance i.e. 17cm.
object
5 cm
20 cm
45 cm
Best
distance
1- coin
clear
clear
blurred
24cm
2345678-
61
On site
Worksheet- Telescopes
o For this exercise, look through the telescopes on the rooftop.
o Choose three buildings to look at.
o Write down their names. Use the information plaques on the
terrace to help you.
o List a few characteristics you notice on them (blue door, sale sign
in the window, etc.)
o Note the type of telescope you are using for each building:
monocular or binocular.
o Edinburgh Castle is to the west. In which directions are your
chosen buildings?
Name of my What I can Monocular/Binocular Direction I am
chosen buildings see on them
telescope
looking at
1-
2-
31-
2-
3-
1-
2-
3-
62
LEVEL D
STRAND:
Energy and Forces (light and
sound/action of lenses).
AIMS:
• To develop a basic
understanding of the
way the eye perceives
colour.
• To
identify
the
relationship
between
pigment and colour.
•
To
identify
the
relationship
between
light and colour.
FACT FILE
The retina of the human eye is formed of three receptors. They
detect light from the three main colours: green, red, and blue.
Light waves enter the pupil of the eye at different intensities and
stimulate the retinal receptors in a variety of ways. Signals are then sent
to the brain and this is how the human eye can perceive millions of
colours.
White light, as we know it, is formed of different light components
mixed together. A prism can be used to break these colours apart. Of all
the spectrum colours, only red, green and blue are used to form just
about any other colour we see.
The process of mixing ‘light’ colours is called additive. By adding a
colour to a second, you are also adding light intensity. The resulting colour
is actually brighter than its components. Have a look at this chart.
63
Red + Green
Red + Blue
Yellow
Magenta
Blue + Green
Cyan
Yellow + Magenta +
Cyan = White
Pigments work the complete opposite way. The process of mixing
pigments is called subtractive because the more colours you add, the
darker the result.
Contrary to what most people think, blue, red and yellow are not the
primary subtractive colours; magenta, cyan and yellow are. Have a look at
this second chart.
Magenta + Cyan
Cyan + Yellow
Yellow + Magenta
Blue
Green
Red
Blue + Green + Red
= BlackBlack
In the classroom
Pigments and Filters
Resources: white sheets of paper, felt markers, red and blue and green
acetate. Children can work in pairs.
Procedure:
1) Ask the students to make five large dots on a white sheet of
paper, using different coloured felt pens: red, blue, green, yellow
and black.
2) Using a red cellophane filter, cover the dots over. What colours
are the dots now? Which dots completely disappear under the red
filter?
3) Repeat the process with a blue and a green filter using the same
dots.
4) Can pupils predict the results of their experiment? They can use
the activity sheet to record their observations.
The Stroop Effect
At the end of this chapter, you will find a card entitled The Stroop
Effect. Encourage children to say aloud the ink colour of each word they
64
see. This famous test in psychology is there to prove that words and
colours don’t always agree. It should be a fun activity to do.
Colours in the Dark
Dim the lights in the classroom. Show a variety of coloured cards to your
pupils and ask them to write down the colours they see on a sheet of
paper. Because of a lack of visible light, the colours should be difficult to
distinguish and may, in fact, all look the same. Once the exercise has been
completed, compare answers to see if some children got some of the
colours right. Which ones were easiest to see? Repeat the experiment,
this time in a darker room. Show the coloured cards in a different
sequence and compare answers at the end.
At Camera Obscura and World of Illusions
Coloured Shadow Wall (Edinburgh Vision)
How it Works
Because the green, blue and red
lights are projected with equal
intensity, the screen you see
appears white, and not coloured.
By walking in front of that
screen, you block some of these
coloured lights. If you block one
light (red), you get a shadow of
the mixture of the other two
(blue + green=cyan). If you block
two colours (red and blue), you
see a shadow of the remaining
colour (green). (See diagram
above.)
Ask and do:
o Name the colours you see on the lights opposite the white screen.
At this stage, make sure no one is in front of the screen. What
colour is the screen? Why is it not red, green or blue?
65
o In groups of three or four at a time, stand in front of the screen
and slowly move your arms and legs. How many colours can you now
see? Can you name them all?
o Can you find black shadows on the screen? How is this happening?
(Because light from all three lamps is completely blocked.)
o Try mixing light and pigments by placing coloured cards on the
screen one at a time so that light can be projected onto them.
Predict the results. What colour will appear on a red/blue/green
piece of cardboard?
66
In class
Worksheet- Pigments and Filters
o Use coloured felt pens to draw five dots on a white sheet of paper:
blue, red, green, yellow and black.
o Put a coloured acetate sheet over your dots. (either blue, red,
green or yellow)
o What do you notice? Some dots disappear, some are harder to see
and some stay the same. Try different coloured acetates.
o In the table below, tick the dots which you can clearly see and put
an X for the dots which aren’t easy to see.
Blue dot
Red dot
Green dot
Yellow dot
Black dot
Blue
acetate
filter
Red
acetate
filter
Green
acetate
filter
Yellow
Acetate
filter
What can you use to break up the light spectrum
into its different colour components?
___________________________________________________________
Sir Isaac Newton was the first scientist
to show that light has different colours.
Find out how he did his experiment
by doing a search on the Internet.
67
The Stroop Effect
Say aloud the ink colour of each word you see
Blue Red Yellow
Pink Green Orange
Orange Purple Blue
Yellow Pink Red
Green Blue Purple
68
LEVEL D
STRAND:
Energy and Forces
(electricity).
AIMS:
• To
prove
that
electricity
needs
a
complete circuit to
flow.
• To show that metals
are conductors.
•
To show that certain
non-metals are also
conductors.
FACT FILE
The giant Plasma Dome in the Electric Room contains a mixture of
the gasses krypton (pink) and xenon (blue).
In the middle of the glass ball, you can see an inner ball, filled with
high, negative voltage metal. This causes the current to flow to the inner
glass of the dome.
Not only is the current flowing, but it is also jumping and pulsating
between the central electrodes and the inner glass. It is moving at such
high speed that a solid stream of purple lightning can be seen. It is purple
because when the electrical charge travels through the gasses, it lights
them up in the process (pink + blue= purple).
If nothing is in contact with the ball, these purple currents flow all
over the dome. Movements appear frantic because all the negative
charges seem to want to get away from each other.
69
By touching the ball, you are drawing the current to earth itself.
(You won’t feel a shock because the charge is too low.) As people conduct
electricity very well, you can attract the current with such intensity that
a bright pink glow can be observed directly underneath your hand.
At Camera Obscura and World of Illusions
The Plasma Dome (Magic Gallery)
You can use this activity as an introduction for a topic on electric circuits.
Alternatively, it can be used to complement a lesson in class.
Resources: Plasma Dome, neon tube (on the wall), metal rod, other
metallic, plastic or wooden objects, spiral fluorescent light bulb, 60 watt
light bulb.
Procedure:
1) Invite students to observe the way the wavy lines travel inside the
dome. Where do they come from? Which direction are they
heading?
2) Invite one pupil at a time to touch the dome. What is happening?
3) Ask 4 children to touch the dome all together at once. What can
you observe? Repeat with 8 or more pupils. Is the result any
different?
4) Get a volunteer to place a hand on the Plasma Dome and the other
on the fluorescent tube mounted on the wall. What happens? (The
bulb lights because your body completes the circuit. The liquids in
your body and the moisture on your skin conduct enough electricity
for this experiment to work.)
70
5) Encourage a few pupils to form a chain by joining hands. The first
pupil should rest a hand on the dome and the last should touch the
neon tube.
6) Add one person at a time to this chain until you cannot light up the
tube anymore. Why are we suddenly unable to produce light?
(Because the circuit is too weak.)
7) Take a metal rod and carefully hold it next to the Dome with your
left hand. With your right hand, try illuminating the mounted neon
tube. Is it working? (Yes, because metal is an electricity
conductor.)
8) Repeat the same experience with different objects (a plastic ruler,
a wooden pencil, etc.) Which of these complete the circuit?
9) Take a spiral fluorescent light bulb. Place it next to the Plasma
Dome. Why is it lighting up? (Because the pulsating field inside the
ball is so strong that it excites the mercury gas inside the tube.
That gas in turn excites the fluorescent coating on the bulb and it
then glows.)
10) Repeat the experiment but with a 60 watt light bulb. What is your
prediction? Why is that bulb not lighting up? (Because there is no
gas involved.)
Crackle Ball (Magic Gallery)
Ask and do:
o Drag your fingers all around
the ball. What’s happening?
o Put your index on top of the
ball, press gently and hold. for
a different effect
o Team up with friends. Put as
many hands as possible all at
once on the ball. Watch it
glow very brightly.
o Hold the palm of your hand on
the ball for a few seconds.
What does it feel like?
o Hold a plastic pen against the
ball, then a key, to see which
materials conduct electricity. Experiment with what you’ve got at
hand.
o Would you be able to activate the ball wearing a rubber glove?
Discuss the question back in the classroom.
71
How it Works
This is one of only 3 crackle balls in the world, and is the only one in
Europe. (One is in Boston, and the other in Toronto, Canada.)
It’s filled with 99.999% pure xenon gas (rarer than gold in seawater).
It is made with a glass ball inside another glass ball. The colour is
from green phosphor coated beads excited by the ultraviolet part of
the xenon light. It moves towards your hand because you act as a
“virtual ground” which grounds the high frequency energy.
Luminglass Plates (Magic Gallery)
How it Works
Luminglass is made using three glass plates which are laminated
together in a computer-controlled kiln. The middle layer of the glass
sandwich has a portion of its centre removed (like a donut hole) and
the resulting space is filled with tiny glass beads coated with a
chemical called a phosphor. The phosphor is what provides the colour
for the gas’s discharge.
After fusing the plates together, an electrode is sealed onto the back,
the air is evacuated and a fill gas is put in. The gas, when energized
with a high voltage, high-frequency power supply, gives off visible and
invisible energy.
The invisible ultraviolet light activates the chemical phosphors on the
beads. The electric filaments of light move randomly between the
beads. They move around because the power supply is turning on and
off very fast, effectively restarting and resetting the pattern each
time. The filaments react to an external human touch because when
someone touches the panel, the body becomes an electrical ground for
the filament to move towards. They also react to sound vibrations.
72
Ask and do:
o Experiment with touch: rub
the plates, tap them, gently
knock on them, etc.
o Experiment with sound: blow
on the plates, whisper, talk,
shout, use low and high pitch
voices. Note the differences.
o The plates are super sensitive, but one seems more sensitive than
the other. Which one is it? How could you explain that?
Lightning Tube (Magic Gallery)
How it Works
A lightning tube is similar to a large-diameter neon tube but the gas
inside and power supply are different. The gas used is at a high
pressure and the power supply often has been slightly modified to
accentuate the movement.
High-pressure gases are used because the higher the pressure, the
thinner and brighter the resulting filament of light. The higher the
pressure, however, the higher the voltage needed to run the tube and
the higher the temperature of the filaments of light. Care must be
taken to use high-temperature, thoroughly stress-relieved glass when
building a lightning tube. The white lightning can be made to move
slowly or very fast by adjusting the fill gas.
Even though it's the same glass tubing used in neon signs, the gas
inside is specially formulated to ionize (glow) in thin streams of light,
much like dancing spaghetti.
Ask and do:
o Grasp one of the tubes with your two hands
and gently drag them from top to bottom.
What’s happening to the tube?
o Join forces with friends to eliminate all
glowing spaghetti by placing as many hands
on the tube as necessary.
o Try conducting electricity with the use of
every-day objects you have on you.
73
In the classroom
Prevention of Accidents
In the electric room, pupils were able to be able to experiment with
electricity in various ways. The experiments were hands on but on a daily
basis, electricity has to be handled with care as they could seriously hurt
themselves.
The key thing to remember is that electricity is always trying to earth
itself and can travel through you. Electrical shocks can sometimes be
fatal. Water also conducts electricity well and just about anything could
become a conductor if wet.
In groups of four, ask pupils to draw a poster showing how they can
prevent themselves from being hurt around electricity. Groups can then
present their work to the rest of the class.
Answers to look for:
o Do not fly kites around power lines.
o Always keep electrical toys and appliances away from water.
o Never touch electrical toys or appliances with wet hands.
o Never use electrical appliances when standing on a wet floor.
o Never touch exposed live wires.
o Never put a metal knife in a toaster. There may be an exposed
wire inside it and the electricity will travel trough the knife and
through you.
o Never pull on the flex when removing a plug from the socket.
o Never put your fingers or objects in sockets.
o Stay away if you see a DANGER-HIGH VOLTAGE sign.
o Stay away from damaged or broken power lines.
o Stay away if there is a leak near electric cables and phone 999.
o Stay indoors during electrical storms.
74
How the Eye Works
Light from all directions enters your eye through the pupil and the
lens.
The pupil can change size to let
more or less light in. When it’s
very bright outside, the pupil
becomes smaller. In dark
conditions, the pupil expands
to take in as much light as
possible. It’s the iris which is
responsible for expanding and
contracting the pupil.
The lens can change its shape to focus the incoming light. When
focussing on distant objects, the lens looks like a thin disc because the
muscles in the eye are relaxing. When objects are closer, these muscles
contract and the lens therefore appears thicker.
Light then travels to the back of your eye to the retina.
(Because light travels in a straight line through the pupil, the
image appearing on the retina is upside-down and backwards.)
The rods and cones (light-sensitive cells) on the back of the retina
change these pictures into an electrical message which can be
recognised by our nerves/ nervous system.
The optic nerve finally transports that message to the brain.
The brain reads the message, flips the upside-down image the right
way up and finally tells us what we are looking at.
Did you know?
Your eyes are well protected. The cornea, a strong and clear membrane,
helps to protect the eye against dust particles and our tears help to wash away
foreign bodies and prevent our eyes from drying out.
The colour of your eyes is determined by the colour of your iris. So when
someone asks you what colour your eyes are, they are in fact asking for the
colour of your iris.
75
Perspective in Illusions
_ _ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ ___ _ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ _
_ _ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ ___ _ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ __ _ __ __ _ __ _ __ __ _ __ _
1
2
Look at the picture 1. Which monster looks bigger?
Are you sure they are different in size?
When you lose the pattern and the converging lines in the background of
picture 1, you can see that the two monsters are exactly the same size
(picture 2).
You were fooled by perspective!
The monster gets bigger the further it travels down the tunnel because
all the lines join up behind him in the distance.
The bricks look smaller towards the back of the tunnel and this is why
the monster appears bigger.
This illusion works well because the object (the monster) is unfamiliar to
you. Your brain assumes the two creatures are different in size based on
their perspectival environment.
----------------------------------------------------------------------------------------------------------------------------
Try this:
Hold your left hand at one arm’s length from your left eye.
Hold your right hand at half arm’s length from your right eye.
Are your hands the same size?
Of course they are, even though one hand is further away than the other.
This is because your brain knows your hands are the same size.
----------------------------------------------------------------------------------------------------------------------------
76
Here are some other examples of the way your
brain is confused by surrounding patterns.
Is that a square in the middle?
Follow the lines with a ruler to find out just how straight the lines are.
Are these two parallelogram table-tops identical?
Put a piece of see-through paper over the first table-top and trace it.
Move your tracing over the second table-top. Amazed?!
A square within a rectangle?
Measure all the angles with a protractor.
Are they all 90 degrees?
77
Which middle dot is bigger?
With a black pen, colour in the outer dots on both images.
Which middle dot is bigger NOW?
Are the red lines wavy?
Use your ruler to discover that they are in fact straight.
A
B
Which portion of the line is longer? (A or B)
With a ruler, measure portion A, then portion B.
Is the diagonal line continuous
or are you looking at two different lines?
Trace over the line with a ruler and a red pen to find out.
78
Mission Target: Camera Obscura
and World of Illusions
Undercover Agents,
Your mission today is to locate and record any unusual
activity you’ll find inside the Camera Obscura and World of
Illusions.
You will be working in groups of 2, 3 or 4.
Each group will receive their own special Mission Target
sheet. There are 4 different Mission Targets to choose
from.
Try to answer as many questions as possible.
Look around the exhibits for clues.
Agents beware! Other teams might be working on the same
Mission as you are. They may try to spy on you and steal
your answers. Keep your Mission top-secret!
Stay with your Mission Commander at all times and listen
for special instructions.
And remember, you are special agents representing
___________ School. Please behave in a responsible
manner.
Enjoy your Mission and Good Luck!
Note to teachers: There are four separate questionnaires for this
exercise. Choose one for each team. This ensures the teams are all
working on different questions.
79
Mission Target #1: Camera Obscura
and World of Illusions
Agents’ names:____________________________________
Your mission today, should you choose to accept it (and you
will!) is to locate and record any unusual activity you find
inside the Camera Obscura and World of Illusions.
Good luck!
Commence Mission Immediately
Level 2-Edinburgh Vision
Look at the photographs on the wall as you come in.
Find the clock on ‘Maule’s Corner’. What time is it?
_______________________________________________
Try the ‘Stereoscopes’. What’s hanging on the gate of
Johnston Terrace?
_______________________________________________
Level 3-Light Fantastic
Find the ‘Prothese’ hologram. What do you see when you
look down the barrel of the gun?
_______________________________________________
What does the ‘Mummy’ appear to be scratching?
_______________________________________________
80
Level 4-Magic Gallery
What happens when you touch the ‘Giant Plasma Dome’
with your left hand and the fluorescent tube with your right
hand?
_______________________________________________
How many mirrored faces can you count inside the ‘Fibre Optic
Kaleidoscope’? ____________________________________
Can you make the shadow of a bird on the ‘Shadow Wall’? Use
the chart on the wall to help you.
yes/no
Level 5-Camera Obscura
When was this Camera Obscura built?
_______________________________________________
Name two things you can use to pick up people.
__________________
__________________
Level 5-Rooftop Terrace
Can you name the two distinctive monuments on Calton
Hill? Use the plaques on the railing to help you.
__________________
__________________
Is the Firth of Forth to the north or to the south?
_______________________________________________
Mission #1 Complete. Return to Base.
81
Mission Target #2: Camera Obscura
and World of Illusions
Agents’ names:____________________________________
Your mission today, should you choose to accept it (and you
will!) is to locate and record any unusual activity you find
inside the Camera Obscura and World of Illusions.
Good luck!
Commence Mission Immediately
Level 2-Edinburgh Vision
Look at the ‘North Bridge’ old print on the wall. What is
the man on the ladder doing?
_______________________________________________
Find the ‘After Marriage’ Stereoscope. What’s on the woman’s
hat?
_______________________________________________
Level 3-Light Fantastic
Find the ‘Microscope’ hologram. What do you see when
you look down the eyepiece?
_______________________________________________
Name three things the ‘Girl with Mirror’ is holding?
_______________
_______________
_______________
82
Level 4-Magic Gallery
What happens to the ‘Luminglass’ when you speak to it?
_______________________________________________
What colour is actually inside the ‘What’s inside the box’
exhibit? ________________________________________
Using the ‘Bendy Mirrors’, can you make yourself very short?
Can you give yourself a long face?
yes/no
Level 5-Camera Obscura
What is the table made of and what colour is it painted?
__________________
__________________
What 3D engineering masterpiece do the cars and buses cross
on the Royal Mile?
_______________________________________________
Level 5-Rooftop Terrace
Can you name three islands on the Firth of Forth? Use
the plaques on the railing to help you.
_______________
_______________
_______________
Is Edinburgh Castle to the east or to the west? __________
Mission #2 Complete. Return to Base.
83
Mission Target #3: Camera Obscura
and World of Illusions
Agents’ names:____________________________________
Your mission today, should you choose to accept it (and you
will!) is to locate and record any unusual activity you find
inside the Camera Obscura and World of Illusions.
Good luck!
Commence Mission Immediately
Level 2-Edinburgh Vision
Look at the ‘Pinhole Photographs’ on the wall. What’s
written on the van? ‘First with the latest ___ ___ ___ ___’
Try the ‘3D Viewers’. What’s happening above the Forth Rail
Bridge?
_______________________________________________
Level 3-Light Fantastic
Locate ‘The Scream’ hologram. What does the woman
appear to be eating?
_______________________________________________
Is ‘Sophie’ a hologram or a painting?
_______________________________________________
84
Level 4-Magic Gallery
Which creature is bigger? Use the disc attached to the
wall to find out.
_______________________________________________
Who wrote ‘It’s not an optical illusion, it just looks like one’?
_______________________________________________
Stand in front of ‘Cubism’, a little distance away from the
exhibit. Now walk sideways, very slowly. Are the pictures
following you? yes/no
Level 5-Camera Obscura
Who built the Camera Obscura?
_______________________________________________
Which of the following can affect the picture quality? (Circle)
a) Fog
b) Rain
c) Passing planes
d) Clouds
e) Flying Balloons
f) Night time
Level 5-Rooftop Terrace
Can you name two of the seven hills of Edinburgh? Use
the plaques on the railing to help you.
__________________
__________________
Is Princes Street to the north or to the south? ___________
Mission #3 Complete. Return to Base.
85
Mission Target #4: Camera Obscura
and World of Illusions
Agents’ names:____________________________________
Your mission today, should you choose to accept it (and you
will!) is to locate and record any unusual activity you find
inside the Camera Obscura and World of Illusions.
Good luck!
Commence Mission Immediately
Level 2-Edinburgh Vision
Look around the ‘Pinhole Photography’ room. Name three
items used to make a pinhole camera.
_______________
_______________
_______________
Is this statement true or false? The ‘Anaglyph’ images appear
3D when you cover your left eye with a green filter and your
right one with a red filter. ___________________________
Level 3-Light Fantastic
Find the ‘Artificial Hip Joint’ hologram. What type of
tool is used for the operation?
_______________________________________________
How many guns can you count on ‘The Ship’? ______________
86
Level 4-Magic Gallery
What continent can be seen from the giant lit-up
‘Lenticular’?
_______________________________________________
How many times can you see yourself in the ‘Giant Kaleidoscope’?
_______________________________________________
Try to ‘Shake Hands’ with you ghost. Can you now join two
pencils together using the same exhibit?
yes/no
Level 5-Camera Obscura
What’s at the top of the tower and used to reflect the
city onto the table?
_______________________________________________
The first photos, film and television images were all in black
and white. The first camera obscura pictures were… (Circle)
a) in colour?
b) black and white?
c) red only?
Level 5-Rooftop Terrace
Can you name two churches in Edinburgh? Use the
plaques on the railing to help you.
__________________
__________________
Is the Royal Mile to the east or to the west? ____________
Mission #4 Complete. Return to Base.
87
Back in the classroom
Answer Sheet
Mission 1
Level 2: It is 3.55pm on the clock. / Washing is hanging on the gate.
Level 3: An eye can be seen looking down the barrel of the gun. / The
‘Mummy’ is scratching her right cheek.
Level 4: The neon tube lights up. / There are three mirrored faces on this
kaleidoscope.
Level 5: The Edinburgh Camera Obscura was built in 1853. / You can use
your hand or a white piece of paper to pick-up people.
Level 5: The Nelson Monument and the National Monument are on top of
Carlton Hill. / The Firth of Forth is to the north of Edinburgh.
Mission 2
Level 2: The man is fixing a light. / A bird can be found on the woman’s
hat.
Level 3: You see a microchip by looking down the eyepiece. / The girl is
holding a parasol, a mirror and a bunch of flowers.
Level 4: The ‘Luminglass’ appears to be producing fast moving purple
lightening strikes. / The box is painted white on the inside.
Level 5: The table is made out of wood and painted white. / The cars and
buses were crossing a paper bridge.
Level 5: The three islands are Inchkeith, Incholm and Inchmickery. / The
Castle is to the west of the Camera Obscura tower.
88
Mission 3
Level 2: The missing word is NEWS. / There is a large fireworks display
above the Forth Bridge.
Level 3: The woman seems to be eating broken glass. / A hologram was
superimposed on a painting to create ‘Sophie’. / Three guides had their
photo taken in 1991.
Level 4: You can help yourself to sweets. / Phil White is the author of the
amusing quote. / The pictures should be following you.
Level 5: Maria Teresa Short built the Camera Obscura. / Only planes,
birds and balloons won’t affect the picture quality.
Level 5: Carlton Hill, Castle Rock, Arthur Seat are three amongst the
seven hills of Edinburgh. / Princes Street is north of the Camera Obscura
tower.
Mission 4
Level 2: Soft drink cans, biscuit tins and wooden boxes can be used to
build a pinhole camera. / The statement is false although the opposite is
true.
Level 3: A screwdriver can be seen on the hologram. / You can count two
canons on the ship.
Level 4: The continent is Africa./ You can see yourself an infinite number
of times in the kaleidoscope.
Level 5: A mirror is used to reflect the city onto the table. / The picture
has always been in colour because it is a reflection.
Level 5: The Tron Kirk and St Giles Cathedral are amongst a large number
of churches in Edinburgh. / The Royal Mile is east of the Camera Obscura
tower.
89
INDENTIFIED
RISKS / HAZARDS
Falling
Slipping if icy
Tripping in dark.
Claustrophobia.
Fear of the dark.
Electric Shock
Burning
Tripping over step stools.
Fear of spiders.
AREA
ROOFTOP
CAMERA
MAGIC GALLERY
EXHIBITS WITH LIGHTS
HOLOGRAMS
Step stools are red.
Sign up at entrance re Spider hologram
Low wattage bulbs and warning signs on
Shake Hands exhibit
Voltage controlled.
Lights off only once all are stationary.
Handrails in Camera.
Door opened if anyone claustrophobic or fearful
All areas railed.
Salted first thing each day in cold weather
PROCEDURE/PRECAUTION
MANAGEMENT
VISITOR HEALTH & SAFETY PROCEDURES AND PRECAUTIONS
CAMERA OBSCURA & WORLD OF ILLUSIONS
Minimal
Minimal
Low risk
Minimal
Minimal
90
Minimal
Supervision by group
leaders required.
RESIDUAL RISK
Fire
WHOLE BUILDING
SHOP
Falling
STAIRS
No risk associated.
Alarm system linked to Fire Brigade. Smoke detectors.
Self closing doors 'Class O', the protected 2 stairs.
Regular staff training.
Brightly lit white walls, kept clear of obstructions,
stairs washed regularly.
Minimal
91
Minimal
Supervision by group
leaders required.