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This chapter describes test CCD test package that can be used to
check the performance of the CCD detectors used.
In order to ensure the quality of the data delivered by the CCDs on
La Silla, ESO run a programme to monitor all CCDs available at the
Observatory. In this CCD monitoring programme, for each CCD test
for each CCD data is collected on regular intervals. A standard
data to check the performance looks like the following one:
- 9 bias frames;
- 16 pairs of flat fields (both of each pair have the same
integration time) using a stable light source and with exposure levels
ranging from just above bias to digital saturation;
- 9 low-count-level (of order a few hundred electrons per pixel)
flat-fields with stable light source;
- one flat-field exposure obtained with 64 rapid shutter cycles;
- 3 30-minute dark images;
- the time taken to read out and display an image.
The quality of the data collected is checked using a number of commands
and procedures available in the MIDAS CCDTEST context. Although the
composition of the calibration data of the user is most not
identical to ESO's test data set, the same CCD commands can still be
executed to check the quality of the user's calibration data.
Rein Warmels
Mon Jan 22 15:08:15 MET 1996