Here`s a guide to starting up and shutting down the Gratama

Introduction!
Blaauw Observatory
Marc Verheijen!
!
Room 284!
Tel: 050 - 363 4077 (w)!
050 - 556 8383 (h)
Blaauw Observatory
Bernoulliborg, 5th floor, room 05-15
Coordinates :
6 32 11.2 East!
53 14 24.9 North!
25m Altitude
Telephone : 050 - 363 8641 (control room)!
8640 (dome)
Prepare for observations
• Check the weather forecast.!
( http://www.weeronline.nl , http://www.sat24.nl) !
!
• Check availability on the Room & Facility Booker.!
( http://www.astro.rug.nl/intranet/computing/roombooker/rbooker.php ) !
!
• Check object visibility.!
( http://catserver.ing.iac.es/staralt/index.php )!
!
• Activate your Linux computer account.!
!
• Bring warm clothes and a midnight snack.
From dusk to dawn on September 21
Sun distance!
below horizon
Sunset!
:
Civil twilight!
:
Nautical twilight!
:
Astronomical twilight! :
Astronomical dark! !
Astronomical twilight! :
Nautical twilight!
:
Civil twilight!
:
Sunrise
:
19:34!
19:34 - 20:11!
20:11 - 20:53!
20:53 - 21:36!
!
( 0° to -6°)!
( -6° to -12°)!
(-12° to -18°)!
!
05:22 - 06:05!
06:05 - 06:45!
06:45 - 07:23!
07:23
(-18° to -12°)!
(-12° to -6°)!
( -6° to 0°)!
Observing is possible from 20:30 to 06:15.!
(10 hours only)
No electronic lock.
control room
• Inform guards of your arrival (5520).!
• Turn off building ventilation.!
• Open emergency escape route.
• Unlock door to dome.!
• Note light switches.!
• Turn on main dome light.!
(bulky red lever)
You should find the
telescope parked at zenith.
Desk with remote
control and dome keys.
Main telescope : !
Guide telescope : !
400 mm Ritchey-Cretien!
3200 mm focal length (F/8)!
175 mm central obstruction
140 mm Maksutov!
2000 mm focal length (F/14.3)!
35 mm central obstruction
CCD camera : SBIG STL-6303E !
: 3060 x 2040!
Science CCD : # pixels!
:
9
micron !
pixel size !
0.12 to 3600 seconds!
Exposure times!:
seconds!
Read-out time! : 14
:
0.580
arcsec/pix!
plate scale!
arcmin2 !
Field-of-View ! : 29.6 x 19.7
: 657 x 495!
Guide CCDs : # pixels!
: 7.4
micron !
pixel size !
Exposure times!: 0.001 to 3600 seconds!
seconds!
Read-out time! : 3
: 0.477 (intern), 0.763 (extern) arcsec/pix!
plate scale!
Field-of-View! : 5.2x3.9 (intern), 8.4x6.3 (extern) arcmin2 !
Filters
: Broad-band! : U, B,V, R!
Narrow-band : Hα, Hβ, [OIII], [SII]
Use keys to turn on the dome switch boxes.
Dome slit control.
Dome rotation control.
Properly set the remote/panel control switches.
Open the dome slit with the remote control.
1. Press Start -> Upper Shutter Open.!
2. Wait for Upper Shutter to open 50cm.!
3. Press Start -> Lower Shutter Open.
Note!
time delay.
Turn on dome relais box.
You should find all plugs
removed from their sockets.
Power up
2. Focuser &!
mirror fans
1. Telescope tracking
(time switch)
up
3. CCD!
camera
Turn on telescope tracking system.
Remove lens covers of
guide scope and finder.
Carefully remove
mirror covers.
Point telescope to !
Dec.≈0deg and HA=0hr
Place covers in cabinet.
Turn on mirror fans.
You should find the Kapteyn!
account to be active but!
Login as Observer
Start programs only !
with desktop icons.
First start FocusMax (takes a while). !
This automatically launches CCDSoft.
Start cool-down of camera (∼35 deg below ambient).
Open a window on the data archive located on Vega
and create the following directory structure:
yymmdd
STL-6303E
i
g
ST-7
i
g
Display the directory where the images will be saved.!
( view → details)
For autosaving the images, turn AutoSave on/off.
Specify: 1) Starting number (1)!
2) File name prefix (yymmdd_Li_)!
3) AutoSave folder (on Vega)
Be very careful when using AutoSave. !
File numbers get easily messed up!
Open the web browser with weather information.
Start TheSky6 to control the telescope pointing.
Establish the communication link with the telescope.
Set the approximate pointing to Dec.≈0deg and HA=0hr!
by clicking at that location on the sky, then click Sync.
First start the dome Server, !
then start the Dome Control interface.
Dome logistics
magnet
park position
switch
Move dome out of its
park position …!
!
( > goto +35 )
... and calibrate its zeropoint.!
!
( > calibrate )
Start automatic dome tracking. ( > track )
Start the Guide CCD positioner interface and click
Initialize
Open the Cassegrain shutter in the camera adaptor.
(pull out the strip gently)
Now the filters are exposed to the open air .....
Now you are ready to take sky flat-fields.
•
If observing just 1 object, point the telescope halfway
the path the object will follow along the night sky.
Otherwise, point the telescope at zenith.!
•
Accumulate ~40.000 counts during an exposure time
of 5-10 seconds.!
•
•
•
Offset the telescope ~1’ between exposures.!
Collect about 5 exposures per filter.!
Start with the narrow-band filters Hβ, [SII], [OIII]
and Hα, before the broad-band filters B,V, R and I.
Once it’s dark enough to see the brightest stars, point the
telescope to a known bright star in the south (e.g. Altair).
Refine the pointing by centering the bright star !
in the small finder crosshair.
Use the handset with a low slew rate (30x).
Take an image of the bright star (3x3 binned, Texp=0.1 sec)
Center the star in CCD crosshair using telescope
motion controls and take new image to check position.
Once centered, re-‘Sync’ the telescope pointing.
Focus the telescope
on an isolated !
5th magnitude star.
FocusMax works
together with
CCDSoft to take a
series of exposures.
If successful, FocusMax
automatically moves
the camera to the
best focus.
Take note of focus position
and mirror temperature.
Broad- and narrow-band filters
have different glass thickness and
require a refocus when switching!
Calibrate the autoguider on a 5th magnitude star.
First select the external guide CCD.
Point the guide CCD to a star.
Take an image with the external guide CCD and
center the star with TheSky6 Motion Controls..
Calibrate the autoguider.
Don’t forget to enter the declination of the star.
Check the calibration results.
The X,Y offsets !
should be roughly perpendicular.
When ready, turn off the mirror fans.
weather !
!
webcam
TheSky6
CCDSoft
FocusMax
image!
archive
dome !
control
Now you are all set to observe!
Make careful notes on observing log sheets.
Use UT times, note weather conditions and anomalies.
Closing down:
Disconnect CCD camera
Closing down:
Exit !
CCDSoft and FocusMax
Closing down:
Exit !
Guide CCD positioner
Closing down:
• Stop dome tracking!
!
• Rotate to calibration point!
!
• Goto park position (-30)
Closing down:
Terminate telescope communication link.
Closing down:
Exit TheSky6
Do NOT save changes.
Closing down:
Close shutter and
fully retract focus tube.
Closing down:
Cover mirrors and lenses!
and park telescope at zenith position.
Closing down:
Turn off tracking,
dome relais boxes,
and remove plugs.
Checklist
•
•
•
•
•
•
•
Turn off all lights in dome.!
Lock door to dome.!
Log out of Observer and Linux accounts.!
Turn off lights in control room and on terrace.!
Make sure door to terrace is closed.!
Inform guards of your departure (5520).!
Lock door downstairs of control room.