View Single Post
  #2  
Old 20-09-2021, 12:32 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Sydney
Posts: 21,857
Couple of things come to mind. Changes in temperature, changes in focal length and focus, aberrations due to uneven glass stress.
Reply With Quote