Pixel Size: 21x21 microns
The quantum efficiency of S2KB is given in this figure. The abscissa is wavelength in nanometers and the ordinate is dQE (%).
Here are some of the original calibration frames for S2KB.
There is a hot column in the overscan region, [2066:2066,1:2048]. Check for the presence and position of this column in your data. You will probably NOT want to use the default BIASSEC in CCDPROC, but rather set BIASSEC to [2053:2064,1:2048] or a similar region of your choosing.
More recently, S2KB has developed an enhanced bias level in one corner amounting to a peak of ~1500 ADU above an overall level of ~965 ADU. This bias exposure shows this effect. The enhancement is limited to the region X < ~240 pix and Y> ~1800 pix.
You can estimate exposure times for S2KB using the CCDTIME package in IRAF v2.11.3 which should still have the necessary information in its ccdtime$kpno.dat database file. If it does not, here is the kpno.dat file.
Click here for the latest on scattered light and over-illuminiation.