Handout: Close-up Photography 8 MB

7/6/2016
What are close-up
and macro photography?
Close-up photography - photographic images taken
close to the subject typically with magnifications of
~0.1X to 1X.
Close-up and
Macro Photography
Macro (or micro) photography - images taken with a
magnification of 1X (or full size) , i.e., the size of the
object is reproduced at the same size on the camera’s
sensor or film.
Extreme macro photography - images taken with
magnifications higher than 1X to ~15X
Michael K. Miller
CCOR July 12, 2016
Photomicroscopy or photomicrography - images taken
with a variety of microscopes at magnifications
between ~10X and >1,000,000X.
Macro a prefix from the Greek for long or large
Field Ion Microscopy
~5 million X
each spot is an atom
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Overview of the Different Techniques
Small objects
1.5 mm, 0.06 in
90%
of
frame
The tools that you require to
photograph small objects depend on
the physical size of the object and its
distance to the camera.
Lenses near minimum focus distance
Point and shoot cameras in macro mode
Macro lenses
Close-up lenses
Magnification is size of the image
compared to the size of the subject
Reversed lenses
~7.4X magnification
24 x 36 mm sensor
Extension tubes and bellows
Macro photography was first practiced somewhere between 1835 and 1839 by
Englishman William Henry Fox Talbot (1800–1877).
However, the term photo-macrograph (macro) was later proposed in 1899 by
W. H. Walmsley for close-up images with less than 10 diameters magnification.
The German Fritz Goro (Goreau 1901-86) is sometimes credited for inventing
macrophotography, making visible the world that lies between the microscope
and the naked eye.
Early macro SLR lenses: 1955 Kilfitt Makro-Kilar 4 cm f/3.5 for Exakta 35mm SLRs
1959 Nikon 13.5cm f/4 Q: 1961 Nikon 5.5cm f/3.5 Micro
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Twin (or stacked) lens configuration
1X
5X
10X
15X
Practicalities
Lighting at small working distances
Positioning subject
Resolution verses DOF
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Focus Stacking
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Regular camera + telephoto lens
near minimum focus distance
Visualizing magnification
8X
4X
6 x 9 mm
2X
2X
12 x 18 mm
1X
1X
Height
of
subject
A nickel is
1/16 inch or
1.58 mm
thick
0.5X
3 x 4.5 mm
The minimum (or close) focus distance is the shortest distance from
the sensor plane to the subject at which a lens can focus.
The working distance is the distance from the front of the lens to the
subject.
Telephoto lenses, either handheld or on
a tripod, can enable capture of images
when the subject is sensitive to close
approach or is moving.
Wide postage stamp
24 x 36 mm FF Sensor
Once you know the size of your
subject then you can choose
the optimum equipment to
record its image.
Nikon Lenses
2:1 = 2X – twice size on sensor
1:1 = 1X – same size on sensor
1:2 = 0.5X – half size on sensor
5
1 inch = 25.4 mm
© Michael K. Miller
Nikon D800 with 80-400 mm lens @ 400 mm, f/8, 1/1000s, 800 ISO
handheld in boat
W.D. inch
Mag.
70-200 f/4
30.5
0.27X
70-200 f/2.8
45.3
0.25X
300 PF f/4E
47.6
0.24X
80-400 f/4.5-6.3
59.0
0.20X
200-500 f/5.6E
79.7
0.22X
Olympus 300 f/4
(MFT)
45.3
0.48X, 0.67X
with 1.4X TC
On Full Frame body
US quarter is
0.955 inches
or 24.26 mm
in diameter
Dime is
0.705 inches
or 17.91 mm
in diameter
8X
4X
Hand held
© Michael K. Miller
Nikon D7000 + 70-200mm lens @ 180mm, f/5.6
Extension tubes can be used to reduce the
minimum focus distance (useful for long lenses)
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© Michael K. Miller
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Nikon D810 with 300 mm lens @ f/8, 1/200s, 400 ISO, handheld
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Point and shoot camera in “Macro” mode
Pre-Columbian Gold Museum in San José, Costa Rica
40 mm
Most P&S
cameras have
a “so-called”
macro mode
to enable
photographing
small objects.
Canon G7X in Macro mode
Most P&S
cameras have
a “so-called”
macro mode
to enable
photographing
small objects.
Cropped & hand held
~40 mm high on
sensor at minimum
focus distance in
Canon G7X
1” sensor
size is 8.8 x 13.2 mm
© Michael K. Miller
Therefore, maximum magnification of the G7X is 8.8/40 = 0.22X
Working distance at this magnification is only ~1.5 inches.
Canon PowerShot S100 in Macro mode, handheld
focal length 24 mm (35mm equiv), f/2, 1/30 s, 160 ISO, no flash
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$500
Red-eyed Tree Frog, Costa Rica
Macro lens
Macro lenses have their optical formula optimized
for close-up photography with magnifications up
to 1X (1:1).
Macro lenses are designed with a flat focus
field (rather than the normal curved field) to
provide a uniformly sharp image across the
entire frame.
The magnification increases as the focus distance
decreases to the minimum focus distance.
Magnification Focus distance
© Michael K. Miller
Canon Powershot G7X in Macro mode - handheld
focal length 35 mm (35 mm equiv.), f/3.2, 1/40 s, 125 ISO, no flash 11
Olympus M.ZUIKO DIGITAL
60mm f/2.8 ED Macro
Effective focal length = 120 mm
increased due to 2X crop factor
13 mm
1X
Sensor size 13 x 17.3 mm
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$250 - 40mm
$1800 - 200 mm
Macro lenses
Macro lenses
All true macro lenses can achieve a
1X magnification on the sensor
irrespective of the focal length of
the lens.
Macro lenses are available in focal
lengths from ~15 mm to ~200 mm.
The longer focal lengths have a
longer working distance but are
heavier and more expensive
LIVE subjects
The maximum magnification, 1X, is at the minimum
focus distance.
Use by setting focus at 1:1 distance and move camera along
the optic axis to achieve focus
Some macro lenses suffer from shortening of the
focal length near the close focusing distance,
i.e., the magnification changes dramatically in the
range (0.5X to 1X) 1:2 to 1:1, For example,
Nikon AF micro-Nikkor 200 mm is ~102 mm at 1X
Canon EF 100 mm is ~93 mm at infinity and ~64 mm at 1X
more lighting options + less shadows
less intrusive on live creatures
This change in magnification can make framing difficult.
They can also be used for regular
photography and will focus to
infinity.
Effective f-number increases with magnification, m:
Neff = N(1+m)
Use tethered Live View or a right-angle finder
if necessary
Useful for copying slides and as a portrait lens
1X
Macro lenses typically include the
reproduction ratio 1:2, 1:1 etc.
above the distance scale.
Olympus OM-D E1,
60 mm macro
@ f/7.1, 1/500s,
ISO 200,
handheld
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Nikon 200 mm f/4 macro lens
Canon 65 mm 1-5X Macro Lens
http://www.pierretoscani.com/echo_focal_length.html
can achieve magnifications similar to extension tubes/bellows
$1500
MP-E f/2.8
Manual focus
lens extends
with higher
magnifications
(not an IF lens)
Closest Focusing
Distance
240 mm, 9.6 inches
(from film plane to
subject)
The Nikon 200 mm f/4 macro lens changes focal length dramatically near
the minimum focus distance.
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1X
2X
3X
4X
5X
Working distances
mm
inch
101
4.0
63
2.5
51
2.0
44
1.8
41
1.6
16
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Other methods
Lensbaby and cellphones
~$400
~$70
The Composer Pro Macro Pack includes the
Composer Pro with Sweet 50 Optic, Soft Focus Optic,
Macro Converters
The Macro Converters sit in between the optic and
lens body and allow for focus between 5" and 8.13"
away from your subject.
Macro lens sets to clip
onto various cellphones.
Very close focus distance.
BLIMPS microlenses:
kickstarter.com/projects/blips/
blips/description
© Michael K. Miller
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Nikon D800 + 200 mm f/4 Macro mode; 100 ISO, 3 sec
1X
f/20 used due to the depth-of-field required
Sensor size 24 x 36 mm (FF)
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Close-up (or supplementary) lens
Equivalent to adding reading glasses
~$15 - 75 for set of 3 or 4
Can be stacked (add together the diopters)
Attaches to filter thread on lens
wikimedia.org
Close-up filters come in different powers from +1 to +10 diopters
diopter power = 1000 /focal length of the lens (in mm)
Therefore: +1 = 1000 mm, +2 = 500 mm, +4 = 250 mm, +10 = 100 mm
=
Magnification increases with longer focal lens lenses and/or higher
diopter close-up lenses.
For a 50 mm lens and +4 diopter lens gives a magnification of 0.2X
For a 300 mm lens and +10 diopter lens gives a magnification of 3X
© Michael K. Miller
D800 + 200 mm f/4 Macro @ f/8, 1/250 s, 81 frames, 400 ISO
1X
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The stated focal length of lenses are approximate and can have an error up to ~±5%.
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Achromatic Close-up lenses
$75-$90
250D
+4 diopters
Focal length 250 mm
Suitable for 30-135mm
lenses
$75-$150
An achromatic
lens is able to
emit, transmit,
or receive light
without
separating it
into colors
500D
+2 diopters
Focal length 500 mm
Suitable for 70-300mm
lenses
Working
distance
Canon 250D and 500D
close-up lenses have
2 achromatic elements
to correct chromatic
aberrations.
For a 300 mm lens with the 500D
at ∞ focus
at closest focus
20.25” 515 mm 13 3/8” 340 mm
0.57X
0.86X
Effective
focal length
of 300 mm
lens =
230 mm
© Michael K. Miller
Higher magnifications are possible if the camera lens is focused closer than its ∞ setting
0.8X
D800+200 mm f/4+Canon 500D @ f/8, 72 frame stack, 1/250s, 100 ISO
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Achromatic Close-up lenses
Raynox DCR-250 and DCR-150 have 2 groups and 3 elements
Adapter to fit on
52-67 mm lens
filter ring
35 mm
49 mm thread
Coated
high-index
optical glass
raynox.co.jp
43 mm plastic thread
8 mm
3X @ MFD
200 mm*
macro lens
+ DCR-250
24x36mm sensor
3X = 8x12 mm
Lens
Diopter
N
mm
fnumber
w 200 mm lens
WD
$49 DCR-150
+4.8
208
≈6
145-208 mm
$58 DCR-250
+8
125
≈3.5
99-125 mm
Can be stacked for higher magnifications
© Michael K. Miller
*Lenses change focal length near macro magnifications/distance
For example, Nikon AF micro-Nikkor 200 mm is ~102 mm at 1X
Canon EF 100 mm is 93 mm at infinity and 64 mm at 1X
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1.6X
Nikon D800+105 mm f/2.8 @ 1:1+Raynox DCR250 @ f/32, 13s, 100 ISO24
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Extension tubes
Microscope lens/
infinity objectives
1 or more fit between the camera body and the lens
~$120 for a set of 3 auto tubes
Nikon CFI Plan 10x/0.25NA - 10.5mm WD Objective
for extreme macro focus stacking
5 to 10 X
Tube lens
wikimedia.org
Requires a 52 mm Nikon CFI Plan
adapter plus a step-up ring to fit
onto the filter thread size of the
tube, i.e., a non-macro telephoto
lens.
Best with prime lenses, but
zooms at long end can also work
No optical components
Can be used individually or in sets
Extension
mm
50 mm
lens
none
0.15X
0
450
12
0.24X
0.31
137
20
0.40X
0.49
107
Shorter focal length lenses and/or longer
extensions give higher magnification
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0.72X
0.78
75
12+20
0.64X
0.71
81
There is a significant loss of light.
12+36
0.96X
0.97
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Also reduces working distance and range of focus
20+36
1.12X
1.08
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12+20+36
1.36X
1.24
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auto tubes with electrical
contacts recommended
Magnificat
Working Distance only 10.5 mm
Tube lens must be focused at infinity with aperture wide open
Distance between the lens and the objective matters
100 mm tube lens = 5X, 200 mm lens = 10 X, 300 mm lens = 15 X
Infinity objectives form a virtual image at infinity;
the tube lens takes these parallel rays and focuses them as a real image on the sensor.
Specific to a camera mount
=
!!
" #
!
New CFD ≅ f(cfd*f + cfd*ext – ext*f)/(cfd*ext – ext*f + f*f)
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1:1 Macro 50 mm lens + 50 mm extension
Bellows
G7
fits between the body and the lens
sensor
Stops
lost
CFD
mm
100 mm lens are half these values
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7.2
X
5.3
mm
$825 for Canon
$1001 for Nikon
novoflex.com
Novoflex Auto Bellows for Canon EOS
Bellows are flexible and continuously adjustable
extension tubes (from 40 (0.8X) - 192 mm (3.8X)) that
allow precise extensions and magnifications to be set.
Bellows can also include a tilt-shift mechanism.
Often used together with extension tubes and
reversed lenses for even higher magnifications.
FotodioX Macro Bellows for Nikon F or Canon EOS: $50
Extensions from 40 - 150 mm (0.8X to 3X with 50 mm lens)
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WD
37
mm
Mag
1.4X
Nikon D800 + 50 mm f/1.4 + 68 mm extension @ f/16, 2s, 100 ISO 28
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Reversed lens
Aperture control for
auto focus reversed lens
Reverse ring adapter fits between body and reversed lens
Focus at ∞
Lens bayonet
Aperture Control Filter attaches to and protects the
rear of the lens and can reduce glare in lens like a
lens hood
An inexpensive ~$12
reverse ring adapter
allows a lens to be
mounted on a camera
in the reversed
position.
Not to scale
Bayonet specific
to camera
mount
~$25
Lens filter thread
Aperture ring
Reverse ring adapter
Manual lenses of any
make preferably with
an aperture ring can
be used.
Camera is operated in
manual (M) mode
Adds a filter tread
Male thread
Bayonet specific to camera mount
Filter thread specific to lens
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Auto focus lenses require the aperture to controlled manually
as it is no longer controlled by the camera
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Reversed lens -Magnification
Reversed lens -Magnification
Magnification cannot be calculated for compound (thick) lenses
16-35 mm at infinity focus
22 mm
~1.1X
16 mm 4.6X
20 mm 4X
24 mm 3.3X
28mm 2.9X
35 mm 2X
13 mm
~1.8X
primes
WD @ CFD
23 to 30mm
50 mm f/1.2 lens at f/4
W.D. 86 mm, 3.4 inch
50 mm 1X,
85 mm 0.36X
28 mm f/2.8 lens at f/4
W.D. 53 mm, 2.1 inch
Wide angle lenses give the highest magnification
Wide angle lenses give the highest magnification
Inexpensive but often get soft edges at higher magnifications
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Exact magnification depends on optical formula of each lens
and lens focus distance
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Stacking Lenses/Macro Coupler
14 mm
0.55 inch
dia.
primary
lens
reversed
lens
~$10
wikimedia.org
Couplers often have the same size male
threads on both sides. Use step-up or
step-down rings to match to lenses.
coupler
Use Aperture Control Filter for AF lenses
This configuration consists of a primary longer focal length lens, a macro coupler,
and a reversed shorter focal length lens.
The coupler screws into the filter rings on both lenses.
=
Nikon D800 + reversed 28 mm f/2.8 @ f/16, 1/20s, 100 ISO
$
%
Examples: 50mm + reversed 50 mm = 1X;
300 mm + reversed 20 mm = ~15X
2X
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Stacking Lenses/Macro Coupler
1.6 mm
0.063 in
15X
Vignetting at the corners of the
frame can occur with stacked
lenses due to the aperture of
the reversed lens.
To minimize this effect, set the
focus of the primary lens to its
closest focusing distance.
Sensor size 24 x 36 mm
Nikon D800 with AF-S 300 mm f/4 +
reversed AF-S 20 mm
Working distance ~1.3 inch (33 mm)
Lighting: tactical flashlight focused on
ruler
© Michael K. Miller
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Nikon D800 300 mm + reversed 50 mm f/1.4 @ f/8, 1/20s, 100 ISO 6X36
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Reduction of working range
Methods to get 1:1 (1X) magnification
subject
1. Macro lens at close focus distance
2. Lens + extension tubes of the same extent as the
focal length of the lens, e.g., 50 mm lens with 50
mm extension
3. Stacked lenses of the same focal length, e.g., a 50
mm primary with a 50 mm reversed lens.
4. Reversed 50 mm lens
5. Lens with close-up lens of the same focal lengths,
e.g., a 200 mm lens and a +5 diopter (200 mm)
close-up lens
Min. focus
distance
Close-up lens
subject
Max. focus
distance
Min. focus
distance
Min. focus
distance subject
Max. focus
distance
Extension
tubes
working
distance
infinity
When additional optical
elements are inserted
before or after the
primary lens, the
camera has a much
reduced range of focus
and can no longer focus
at infinity.
In some configurations, the working distance can be less than 10 mm
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Light sources: flash
Lighting the subject
As the working distance in macro can be very small, the
lens blocks much of the ambient light and also the oncamera flash that would normally reach the subject.
Longer focal length macro lenses give more working distance.
working distance
200 mm
working
distance
+windshield
This limits the creativity for
artistic lighting the subject.
60
mm
Back
lighting lightpads
with
diffusers
1-1500
lux
6000K
540 lux
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On-camera flash are blocked by the lens.
Speedlights have a controllable range that is
much longer (~0.6-20 m/2-66 ft) than the
typical macro working distance + too much
power.
Nikon R1 macro flash
Reduce power by using manual flash
Up to 4 speedlights that can be
settings.
positioned around the ring
A ring light goes directly around the lens and
Nikon
SB 200
is aligned with the axis of your lens resulting
in nearly shadowless lighting but may show
rings in the eyes of insects and be dimmer in
the centre of the image.
Two (or more) separate flash heads on
either side of the lens giving a more 3D
lighting effect.
The SW-11 modifiers can
Can be used to freeze the subject.
redirect and diffuse the light
~250 flashes per charge
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Light sources: LED
Tactical flashlight
130 - ~4000 lux
Very bright
Lume Cube
1 to 1500
lumen
DO NOT
TRY THIS
AT HOME
SEVERE
EYE
AND/OR
SENSOR
DAMAGE
POSSIBLE
Light guides
with colour
filters
Relatively inexpensive LED Panels and high intensity LED (tactical)
flashlights with continuous light output up to 4000 lux are available.
Some have adjustable color temperatures ~(3000-6000K) and intensity.
Some LEDs have a blue tint – adjust White Balance accordingly.
WARNING: DO NOT VIEW LED OR SHINE IN PEOPLE OR ANIMALS EYES
© Michael K. Miller
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8X
D800 + 200 mm + reversed 16-35 mm @ 35 mm, f/8, 1/20s, 100 ISO
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Positioning subject in relation to camera
Fleabane
“The small
yellow disk
flowers bloom
from the
outside in.
The white
"petals" are
ray flowers.”
Kris Light
0.6X
© Michael K. Miller
Nikon D800 + 200 mm f/4 + Canon 500D @ f/8 stack, 1/250s, 100 ISO
Single Lume Cube LED light – Auto WB
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At macro magnifications,
vibration and accurate
positioning are major
concerns.
Therefore, sturdy tripods,
ball heads, and good
camera technique is
essential.
The MUP (mirror lock up)
setting and a remote cable
release are often used.
A stable mount for the
subject is also required.
Moving subjects can be
frustrating.
$650 for pair
reallyrightstuff.com
Note scales for focus stacking
Focus is normally achieved by moving
the camera with respect to the subject.
Lab jacks and/or macro 2- or 3-axes focusing
rails are often used for positioning the
specimen and focusing.
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Resolution v. Depth of Field v. Light
Increasing DOF with Focus Stacking
Higher bars better
Focus stacking (or blending/Depth of Field (DOF) stacking) enables the DOF of
an image to be increased by combining multiple images taken at slightly
different focus settings or subject-to-camera distances.
Allows non-planar and subjects not parallel to sensor to be photographed.
Olympus M.ZUIKO
60mm f/2.8 ED Macro
DLA = 6.78*1.61 = 10.9
Corrected for sensor crop factor
DLA Diffraction limited aperture – sensor pitch in microns X 1.61
smaller
The choice of the aperture setting is a compromise between resolution/diffraction
effects, depth-of-field (DOF) and amount of light required.
Macro lenses are similar to other lenses in that the resolution typically
increases until the refraction limited is reached at small apertures.
The DOF increases at smaller apertures and is distance dependent.
Light increases with larger apertures and longer exposures
The DOF is extremely small at macro working distances
Simplest to place specimen parallel to sensor plane (parallelize the subject)
DOF defines the optimum step size for focus stacking - >20% overlap.
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Image capture for focus stacking
Example below is a ruler set at 45° to focal plane of camera
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3
In depth how to tutorial is available on the CCOR website
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2
3
4
5
6
7
8
6
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Some stacking software will suggest and set the step size for the
camera lens or the focusing rail between the frames
4
Step size = 2 c n (m+1)/(m x m)
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focus stack of 72 frames at f/8
How many frames and optimum step size
A series of images at different focus or distances are captured.
1
Single frame at f/8
Most often used for macro photography but can be use for other subjects, such as landscapes.
c = circle of confusion
n = f-number
m = magnification
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After capture, a focus stacking program is used to
automatically align and choose the in-focus regions
of each image to combine into the final image.
The shape of the in-focus regions depends on the
depth profile of the subject.
The output may be a single jpg, tiff, or dng file of
the stacked image.
Use at least a 20% overlap.
Steps can be extremely thin when
very close to subject
Thinner than a credit card (0.76 mm)
@ 1X = 0.45 mm with a 20% overlap
@10X = 0.025 mm with a 20% overlap
Out-of-focus bands
(known as focus banding)
of can be observed in the
focus stacked image when
the step size is too small
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Focus Stacking methods
1.
2.
Turn the lens focus ring manually by hand
Automatically step the focus motor inside your lens with software, e.g.,
ControlMyNikon™, CamRanger™, Helicon Remote ™, digiCamcontrol, etc.
3.
Move the camera (or subject) with a focus rail, or automatically with
StackShot™ Macro rail package (cognisys-inc.com)
DOF 4” or
100 mm
Must have a compatible autofocus lens with a computer chip
Simplest to tether the camera to a computer.
$550-850
Very time-consuming.
Subject or camera must not move
Optimum with extended distances and when shooting at 1:1 magnifications,
i.e., when at end of focus range (no + focus may be available)
Stacking software is then required to combine the images.
$115
$200
$240
See tutorial
on CCOR
website
$89
$189
$289
See en.wikipedia.org/wiki/Focus_stacking for other software
Short stack – up 20 frames: Tradition stack – up to hundreds of frames
Clean sensor before starting.
sensor spots will appear as dark lines
stuck pixels will appear as coloured lines.
© Michael K. Miller
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D800 + 200 mm Macro @ f/8, 148 frames @ 1/250s, 400 ISO
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Parameters for the Depth Map method
Setup for Stackshot™ operation
“Pyramid” (Pmax) method has NO adjustable parameters
Camera’s
USB port
“Depth map” (Dmap) method finds the source image where the sharpest pixel
is located and creates a "depth map" from this information.
Radius and Smoothing parameters
USB port 1
USB port 2
Shutter release
The Radius Parameter: Radius is the most important parameter. Start from the default
value (8 HF/10 ZS) and then set it to its minimum (1) and observe the changes. Then
increase the value to get rid of any noise or artifacts, particularly halos along the edges.
If your image has fine details and thin lines, a low radius level (3-5) will probably yield the
best results, although you will probably get more noise and a halo effect. If there is a halo,
try increasing the radius to minimize halo, then stop to preserve as much detail as possible.
X
110V Power
AC
adapter
The Smoothing Parameter: Low smoothing produces a sharper image, but the transition
areas may have some artifacts. High smoothing will result in a slightly blurry image without
any visible transition areas.
Start with the default smoothing (4 HF/5 ZS). For more detail, decrease the smoothing
value; if get too much noise and too many artifacts, increase the value.
USB power
AC power adapter for camera eliminates the need to change batteries
Minimum step size is 0.002 mm over the 100 or 200 mm travel of the rail.
Connect USB cables directly from computer to camera – no USB hubs.
HF = Helicon Focus; ZS Zerene Stacker (Options> Preferences> Dmap settings
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Popular focus stacking algorithms
“Pyramid” (Pmax) method is very good at
finding and preserving detail even in low
contrast or slightly blurred areas.
It gives good results in complex cases
(intersecting objects, edges, deep stacks) but
increases noise, contrast and glare. It can alter
colors.
Some lens and reconstruction artefacts
“Depth map” (Dmap) method does a
better job keeping the original
smoothness and colors, but it's not as
good at finding and preserving detail.
Images must be in order.
Substack slabbing for troublesome
regions or to overcome large file
size/computer memory issues.
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Halos around edges of objects and in
the out-of-focus background regions
Coloured straight lines running
perpendicularly to the edge(s) of the frame
Strings of dots – sometimes replicated
Dmap reconstructions can introduced noise
similar to sensor spots and stuck pixels
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