See this Comm Center thread by Jeff Lewis. The exposure interval is positive for light images, 0 for bias, and negative for darks.

 

  
SVN Comment
 
 

  
Author
  
rbdenny
 
 

  
Repository
  
svn+ssh://rbdenny@a2_svn_dc3/home/rbdenny/svn/astro/acp
 
 

  
SVN Revision
  
799
 
 

  
Affected files
  
/trunk/ACP Help/addtologic.htm (Modified)
/trunk/ACP Help/relnotes.htm (Modified)
/trunk/Script Components Master/UserActions-template.wsc (Modified)
/trunk/Script Components Master/UserActionsJS-template.wsc (Modified)
/trunk/UserActions-template.wsc (Modified)
/trunk/UserActionsJS-template.wsc (Modified)

 
 

  
Check-in comment
  
Clarify in UserActions ImageStart() that exposure interval of 0 is a bias, and negative is a dark.
GEM:1204