Compute image statistics for an acm image. Initially this was used to understand the ovsercan area of the acm images. What I found was that there is no overscan area. Just bad initial columns.

% acm_global_stats --help  

acm_global_stats:
  Cimpute global image statistics for HET acquisition camera image (acm).

Example: 
  acm_global_stats /home/sco/HET_work/acm_nights/20171108/acm/20171108T044747.8_acm_sci.fits
  See the file acm_global_stats.Explain

To run a bunch of images: 
  acm_global_stats_fitslist list.1 

You will have a table file with basename:  acm_global_stats

You can make a quick plot with: 
  xyplotter_auto acm_global_stats overscan active 1