View Single Post
  #8  
Old 19-02-2008, 06:12 PM
Peter Ward's Avatar
Peter Ward
Galaxy hitchhiking guide

Peter Ward is offline
 
Join Date: Dec 2007
Location: The Shire
Posts: 8,113
So, you are saying we effectively knobble the Canon by introducing a ND filter factor ahead of the Bayer (G_R_B_G) Matrix?

There is considerable interpolation during the debayering and it would be very rare to find an object that emits only one of the primary colours.

The off colour pixels do contribute to the image so I can't see how you get "9x the usable photons" from the CCD....if that were the case, then should have been little difference between the two cameras with broad band emitters (stars)....and it is clear that the CCD is still more sensitive there.

I also wanted to use each camera "as is". Turning off the peltier on the CCD would make as much sense as putting an ND filter on the Canon


Quote:
Originally Posted by avandonk View Post
It is a meaningless 'test' as the Sbig has nine times the usable photons. The Canon only uses a third of its pixels for each colour.

Then test them at the same temperature!

Sorry try again by maybe illuminating the Sbig without any filtration for thirty seconds and the Canon for 30 secs through red, green and blue filters and converting the three images to luminance. Then the test would be more equitable. The IR filter still hampers the unmodded Canon.

Bert
Reply With Quote