== '''Current Status''' ==
GIRAFFE has been mothballed following the failure of its control software, a lack of source code to delve into to fix it and a current lack of staff resources for creating a modern control programme. The instrument was undergoing a series of upgrades to improve performance and provide a data reduction pipeline. This is now on hold, with other instrument projects taking priority.
== '''Brief description of GIRAFFE''' ==
2. A thin client system for data storage ''ltsp.suth.saao.ac.za''.
3. [[APD|A laptop running a LabView program to display the APD counts]], i.e. monitor the light intensity emerging from the fibre.
4. The Linux TCS PC for acquisition and autoguiding.
=='''Data storage''' ==
The PC on which QUARTZ should not be used for any other purpose. The same applies to the TCS. GIRAFFE data should be automatically transferred from the ''giraffe'' PC to the server, which is accessible from the thin client (the monitor to the left of APD counting laptop), where data reduction software, ds9, web browsers, etc. can be used.
You should check that your data is being transferred by logging into the thin client
Username: ccd74
Password: label on monitor
cd /data/74in/giraffe/data/image/yyyymmdd
Your files will be named ''annnmmmm.fits'', where ''nnn'' is your run number.
[[Indlulamithi|Data reduction Software for Giraffe]]
The instrument is controlled by the QUARTZ software on giraffe PC.
'''2.1 Starting the software'''
1) Log on as ''ccd'' (usual password)
* Wait 2 minutes for it to finish initalising.
* Check that things are working, by reading out the CCD by selecting ''Read CCD'' from the ''CCD'' drop-down menu at the top right of the QUARTZ window. This will display information regarding the bias reading and the maximum CCD count.
* Select “Filter” → “Init” at start of run, and again before every filter change.
=='''Setting prism position & determining wavelength range'''==
First [[Determining prism position|determine the required prism position ]] for your desired wavelength coverage.
Then '''at the start of the run or after a software crash''', follow these steps using options available by clicking on the “Init” button at the top right of the QUARTZ window:
== '''Observing''' ==
'''4Acquiring a target''' Before attempting this, you should read about using the [[APD|APD]]. The shabby A4 notebook stored on the bookshelf contains previous "red marker" positions on which to locate a target with the guide mirror in beam. '''Current latest red marker coordinates:''' (218,50) on 23/01/2015. Note that this position shifts slightly after each instrument change, and when pointing far from zenith. To acquire a target: 1 ) On the TCS, with guide mirror in beam, place a red marker on the acquisition image in the previously recorded position (e.g. 218,50). 2) Point the telescope to the target and centre it on the red marker. 3) On QUARTZ "Control" panel, click "APD" to turn on the avalanche photodiode. 4) On TCS, move guide mirror out of beam, and "Go To" XY-slide position (590, -12900) to view the fibre. Target Set acquisition camera exposure time ~2s. 5) On "Piet's Old Laptop", run the APD plotter by clicking on the white arrow and wait for the counts to stabilise. 6) With the hand paddle switched to "Guide" speed, adjust the telescope pointing to centre the star on the fibre. You should see an illuminated disc on the acquisition image, which is the reflection of the star from the small mirror inside the GIRAFFE head (although after an instrument change you may not see this yet). The technique to centring the star is to make small movements of the telescope and use the rising/falling APD counts and brightening/dimming acquisition image to help you centre the star on the fibre. As the star becomes better centred, the APD counts will increase, and a bright disc will appear on the acquisition camera image. 7) Set up a guide star, as per the TCS manual, start target exposureswith QUARTZ, and keep an eye on the APD counts to ensure that the target isn't drifting off the fibre over time. '''Exposing on a target'''
1) Select “ND Pos 1” and “Mir Pos 1” in the QUARTZ “Control” panel
3) Click the “Expose” button in the “Control” panel on the right of the QUARTZ window and enter the exposure time.
4) Take an arc every at the beginning and end of observing a target, and at ~20 minutesminute intervals on that target. == '''Troubleshooting & avoiding trouble''' == * Do not touch the ''giraffe'' PC while it is busy with a procedure - especially during readout - as QUARTZ is likely to crash.* If QUARTZ crashes, or and complains of a Merlin/transputer error, you will need to go to the Coude room, duck under the coolant pipe, locate the blue Merlin transputer on acquiring the shelf below the optical bench and press the ~central red button. Then restart QUARTZ.* If the orders do not match the requested prism position, initialise the prism with "Find ref" and move to the requested prism position again. You may have to repeat this a new targetcouple of times for the prism/camera to reach the requested position. == '''Instrument shutdown''' == * Ensure that the APD and all lamps are switched off.* Ensure that the fibre flat filter (silver knob on telescope) is out of beam, or you may forget it the following night.* Leave the QUARTZ software running (the technicians need to check the temperature of the detector during the day).* Stop the APD count plotting software and shutdown the windows laptop.* If the cryostat was last filled before midnight, please fill it before you leave.* Shutdown the telescope using the printed recipe, stuck to the shelf above the TCS.