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INGRID (Isaac Newton Group Red Imaging Device) is a near-IR camera for use at the 4.2m WHT. At the heart of INGRID is a 1024x1024 Hawaii near-IR detector array for imaging from 0.8 to 2.5 microns, the pixel size is 0.238 arcsec.
Drive AZ and ALT slowly in + direction over the zeroset target points, then switch to computer control again
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.
At Cass, Ingrid uses the large feed mirror (AGINGRID). To use AGCOMP for direct TV viewing (e.g. calibrate pointing), the large feed mirror must be out. While direct TV viewing no INGRID observing is possible.
The focus mechanism inside INGRID is only to compensate for collimator / camera distance i.e. instrument focus, not telescope focus. By correcting telescope focus errors with the instrument focus you risk distortion (astigmatism) in the image.
To begin a nights run, INGRID should be set to nominal focus (-750.0 microns) and a telescope focus run done to determine best value for telescope focus Once the telescope focus has been set, another focus run using the instrument focus can be done (if necessary) to optimize instrument focus.
We have found that the instrument focus is stable and should not change with either temp or filter.
Calibrate telescope pointing:
Imaging is easy - point and expose.
Make sure INGRID is fed by the large feed mirror ICL> AGINGRID.
The rotator is usually kept tracking sky PA 180 (USER> ROT SKY 180).
To copy the TCS info display on taurus.roque.ing.iac.es the startobssys
sequence sends the command 'CLONE ON 22.214.171.124' to the TCS.
The INGRID nightlog is produced from the obslog. Writing the data:
The data is written to DAT tape in the standard ING fashion. To do this, get a DDS3 tape. Open an xterm and change directory to the directory containing the data you want to be written to DAT tape. Attached to the Lupus and Auriga sparcs are DDS3 tape drives, the DAT tapes should be put in there and prepared for data by typing:
Follow the on-screen questions. Next the data should be written by typing:
Again, follow the on-screen questions.
Subject: Using the WHT TCS with INGRID ====================================== Operation of the WHT Telescope Control System (TCS) with INGRID is slightly different from its use with other WHT instruments. This is because the TCS must serve telescope header information to the INGRID Observing System which runs on a Unix-based Sparc ('crater') rather than to the VAX-based system computer ('LPVF/LPVG') used for normal optical observations. During a nights observing it is now possible (since version W12-0-6) to switch the TCS between Vax control (using DECNET communications) and Sparc control (using DRAMA communications), without the need to take the TCS down. This avoids the need to do any time-costly TCS recalibration. Frank Gribbin has produced some notes on how to do the changeover. These may be found in the green "INGRID TO's notes" folder in the WHT; additionally I have reproduced them below at the end of this email. Other points to note: 1. By default the TCS still comes up in DECNET comms mode - ie the link to LPVF/G is active. 2. DO NOT type 'TEL_LINK_TO_TCS' at the LPVF/G ICL prompt when running in DRAMA comms mode. This will totally stuff things up ! Instead, follow the instructions laid down below. 3. The INGRID Observing System does NOT provide support for the "TCS info display". This display is now considered obsolete, its use having been superseded by the new TCS 'CLONE' command. To provide the INGRID Observer (sitting in front of 'taurus') with a TCS display type: CLONE ON 126.96.36.199 4. The current changeover procedure is a bit fiddly and we (the software group) will aim to simplify things in due course. WHT TCS Drama/Decnet communications ----------------------------------- 1) To start TCS with default DECnet communications, either (a) Start ICL system and allow it to start TCS. This starts DECnet communications to Vax system computer. (b) Log on to LPAS4 as WHT_LOGIN password on TO Xterm Select start. To start DECnet communications to system computer type TEL_LINK_TO_TCS at ICL or start the ICL system. 2) To change to Drama communications (for INGRID) Drama communications are necessary for the INGRID control system dither procedures and for collection of telescope headers. With the TCS started as in (1) above : (a) Log into LPAS4 as WHT_LOGIN (b) Enter OPTIONS to select the options menu. (c) Enter COMMS to select comms menu (d) Enter DRAMA to select drama communications (e) Enter TELD to start the drama TELD task (f) On ingrid system enter tcsstat 3) To change to DECnet communications (for ICL+optical CCDs) DECnet communications are necessary for collection of telescope header items by ICL and UltraDAS systems. With Drama communications running as in (2) above (a) Log into LPAS4 as WHT_LOGIN (b) Enter OPTIONS to select the options menu. (c) Enter COMMS to select comms menu (d) Enter DECNET to select DECnet communications. Don't worry if you get message "Dtask failed to die". Ignore and continue. (e) At ICL enter TEL_LINK_TO_TCS (f) Check link by issuing ICL command PAGE and note that TCS display page changes 4) To start TCS with DRAMA communications, either (a) Log on to LPAS4 as WHT_LOGIN password on TO Xterm (b) Enter OPTIONS to select the options menu (c) Enter COMMS to select communications menu (d) Enter DRAMA to select drama communications (e) Enter MAIN to go to main menu (f) Enter START to start the TCS and TELD drama task Version 2.1 Frank Gribbin / Simon Rees 10-Apr-2000
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