Stack a set of images. The iset number is an integer designation that is assigned a set name (such as tht used by the onsky_set routine).

 

% iset_stacker --help   

Example (after a run of AcmRunDate) 
% onsky_set EX1 3 N N 
% iset_stacker 3 List.FINAL_ISET mean  

The stacked image is placed into the ./local_red/ISET_STACKS directory 
with the name:   iset_3_stack.fits
A list of the iput images (list.3) is also placed there. 

Finally, two header cards are added that give stack information. Here 
are the last four header cards of iset_3_stack.fits:
BIASMEAN=           1400.0135 / mean bias subtracted
BIASSIG =              1.0782 / stan.dev. of bias among images
NSTACK  =                 24  / Number of images in stack
NSUBSTAC=                  8  / Number of substack images