PNS MANUAL: Setting up the CCDs

Setting up the WHT CCDs

The WHT EEV 2x4k ccds (EEV12 and EEV13)were used for commissioning. The orientation chosen was such that the spatial direction coincides with the long axis of the CCDs. A little bit of field is lost in the spectral direction this way, but not much.

Windowing the CCDs

The CCDs need to be windowed to keep down the readout times and data volumes. The windows used for PN.S commissioning were:

EEV12 on PNSL: window pnsl 1 "[1:2154,815:3314]"

EEV13 on PNSR: window pnsr 1 "[1:2154,801:3300]"
Marconi2 on PNSR: window pnsr 1 "[1:2154,1076:3575]"

If possible please use the same windows, or at least the same SIZE windows.

This can be done with the call: windowpnsEE (for 2x EEV) or windowpnsEM (for EEV + Marconi).

Readout speeds

Readout noise is rather important as our background levels are low. Readnoise above 5e- should be avoided. At commissioning this meant using slow readout speed. DAS command: rspeed pnsl slow and ditto pnsr.

For all runs prior to October 2002 we had to avoid simultaneous readout as this caused pattern noise and high levels of read noise; with the appropriate controller power supply (labelled USE THIS WITH PNS RIGHT ARM) we were able to readout simultaneously (some patterning, but quantitatively negligble extra noise). Note: there doesn't seem to be any power supply with this label, just two with labels USE WITH PN.S, and a third spare without such a label (the problematic one....)
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