debias runs 'picstat' followed by 'icsub' to remove the bias level from frames. Note that reduce can also do this but debias may be useful for preparation of flat fields etc. For safety, it creates a header item '.more.debias' which if it exists means that it will not attempt to subtract the bias frame a second time, although it will carry on with the action of a constant determined from the bias region.
debias bias_frame bias_region file1 file2 ...
| bias_frame | --- | a mean bias frame to subtract. specify a null frame if you don't want to do this |
| bias_region | --- | is a file specifying the bias region(s) for picstat. |
| file1, file2 | --- | are individual files. |
Author: T.R. Marsh
Created: 14 January 2001
Revised: 08 December 2005