Quote:
Originally Posted by SkyViking
Great info there Ray, which confirms my own experiences with flats. Thanks for posting yet another thorough analysis 
One question, how do you dither flats? With an evenly illuminated flat what is there to dither? |
Depends how you make your flat. If you image a twilight sky then you may pick up some stars. If you image a t-shirt then there may be varying density of threads or whatever across it. If you image an LCD screen like me then they are pixel defects or backlight inconsistencies.
So I move my scope around in front of the screen to "dither". It has the effect of averaging out the inconsistencies.
Cheers,
Cam