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WORKING WITH ULTRACAM
Ultra-fast imaging camera exposing in 3 bands simultaneously through two dichroics, with 5x5 arcmins field.
Mounted at WHT cass, it has Peltier-cooled chips (no need of LN2).
It is fed with cool water by a chiller placed onto the observing floor close to one arm of the mounting fork of the telescope. This chiller is connected to the instrument with two long pipes which hang from cass; these pipes are large enough as to allow telescope movements in DEC and rotator position.
They gave no problems during commissioning (May 2002).
For more information see Ultracam Sheffield page

On 2-May-2004 FJG released W23-1-2. With this new version use INSTRUMENT ULTRACAM. GSS was updated at the same time with an ULTRACAM configuration.

Note: The TCS fall-back version is W23-1-1. With this use INSTRUMENT ISIS.

Startup
TCS:
to zeroset on the targets switch to computer control:
to zeroset absolute: Zeroset absolute will go wrong in case an absolute encoder bulb is broken! When slewing to the first object check azimuth and altitude incremental and absolute encoders are in close agreement and updating.

Autoguider:
Use the standard uDAS autoguider for CASS with AUTOFOCUS 2800. This was last run from leo (whtdas18) with 'obssys 1', 'startobssys' and 'startag AG' followed by 'option 4'. No window is required!
GSS is used for finding guide stars, connect to LPVS3 via LAT and login as GSS.

The probe is moved using the new AG_GUI or using a telnet connection to Taurus. Logon as:whtobs,passw:***** , type obssys and carry on 1, 1 and we'll have the prompt TO> prag Radial Theta.

TV:
AGCOMP mirror is used for direct viewing, finding the rotator center and performing calibrate.
- For observing no mirror is left in, thus OUT from the AG_GUI.

Observing System:
UltraDAS.

Preparation
Telescope focus:
Is determined on the chips, usually by the Ultracam team.

Determine rotator center:
Use direct viewer (AGCOMP) and TV camera(whtdas19).

Calibrate procedure:
Calibrate is done on the rotator center and with the rotator stopped (ROT MOUNT xxx) using the direct view TV.

Determine aperture offset:
There is no need for defining an aperture.

Observing

Twilight dithering:
Vik uses an ICL-script to dither while taking sky flats.
To run the script go the taurus terminal and in the observing system prompt type SYS>spiral.csh, and this start to run the script.

----OLD IDL:.."First ICL> LOAD [.VSD]SPIRAL.ICL, then run it by typing ICL>SPIRAL 10 100 10.
The script is asking you for three parameters. The step size in arcsecs (e.g. 10"), the number of steps (e.g. 100) and the time to wait in each position (e.g. 10 seconds). The script can be terminated by ctrl-c any time. As the script uses 'tweaks' remember to move to the original position before restarting it".----

Acquisition:
Acquisition is done through the camera itself, as it is a fast-reading device for high time resolution observations.

How star moves by XY HANDSET cursor keys:

using the new TCS version W27-1-2:

       +------+
       |  ^   |
       |  |   |
       |  |   |
       |      |
+------+------+------+
|      |      |      |
|      |  |   |      |
|  <-- |  |   | -->  |
|      |  v   |      |
+------+------+------+


using the fall-back TCS version W23-1-1:

       +------+
       |    / |
       |   /  |
       | |/   |
       | +-   |
+------+------+------+
| \    |   -+ | +-   |
|  \   |   /| | |\   |
|   \| |  /   |   \  |
|   -+ | /    |    \ |
+------+------+------+

Autoguiding:
For guide stars use GSS with ULT setup.

Data Handling
The data are numbers of images (up to 2 Gb) stored in a single data file on dedicated Ultracam machines, so the runs do not appear on ING logs.

-------- © 2006 Isaac Newton Group of Telescopes --------
Last Updated: 3 March 2006 Juan Carlos Guerra jcg@ing.iac.es