badgen generates a frame in which all pixels within an input frame that lie within a certain range of values are set to 1 while all the others are set to zero. This can be used to generate bad pixel masks. A bad pixel mask is an ordinary ultracam frame in which good pixels have been set = 0, while bad pixels are set to integral positive values. For instance, take a flat field, smooth it with boxavg and/or boxmed and divide by its smoothed version. Then you can identify all pixels with value below 0.8 (or something) as bad using this routine. You can define several levels of badness with multiple runs of this routine, and add the resulting frames together after multiplication of the individual frames by an integer denoting the level of badness. Avoid the value 10 which I reserve for possible cosmic ray IDs in the future. reduce then stores the worst bad pixel encountered in each aperture in the log file.
badgen input min max output
|min||---||Minimum value to consider|
|max||---||Maximum value to consider|
|output||---||The output frame set to 1 whenever pixel values lie within range|
This command is a member of the classes: Arithematic, Manipulation, Programs.
Author: T.R. Marsh
Created: 29 June 2004