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GIRAFFE

658 bytes added, 23:15, 27 January 2015
/* 2.2 Setting prism position & determining wavelength range */
* Select “Filter” → “Init” at start of run, and again before every filter change
=='''2.2 Setting prism position & determining wavelength range '''==
Do this at First determine the start of the run, using options available by clicking on the “Init” button at the top right of the QUARTZ window: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: 1) Select Initialise the prisms: select “Init” → “Find reference” and wait for “Finding reference...” window to close
2) Select “Init” → “Define red” or “Define blue” depending on the prism you wish to use and enter prism position
4) Check and note down the prism position in the “Prism” status box at the bottom of the QUARTZ window.
5) Take a [[fibreflat|fibre flat]]and an arc exposure (follow steps in Calibrations section). 6) On ltsp, run the data reduction software on the flat & arc files to determine the orders present in the image and the wavelength range. 
6) By taking an arc (follow '''If the calculated orders are far from those expected''', the prisms will need initialising. Repeat steps (1)-2 in Section 3.3(6), check until the resulting expected orders are in the frame. When this happens, the correct prism position is usually achieved over 3 initialisations, but it is important to move the prism after an initialisation, i.e. always follow steps (see section on reductions software1) and spectrograph focus is good with step (see Section 53)(you can skip step (2) because you already defined your desired position); don't do step (1) twice in a row, or GIRAFFE will get quite upset.
=='''Calibrations'''==
Hannah
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