[Aavso-photometry] Light box question]

[BailyHill at aol.com]

Hello Ben
 
Mike did an excellent job of explaining the dither technique.  
 
Like everything in photometry, it has its limitations.  It is very  hard to 
collect enough images to get real high signal to noise ratio in the  flat.  As 
Mike said, you can spend more time doing flats than  observing.
 
The other trick, is to remove the stars from these flats.  For me, I  have 
NEVER been able to make them really go away.  I can always see  residual stars 
at a low level.  Perhaps there is a trick that I do not know  able.  
 
I guess the bottom line is that you must match the flat technique to the  
problem you are working to get the optimum results.  What this probably  means is 
to try several techniques, and see which answer you like.   This technique 
will not always be the same.  I can tell you that I spend  some time almost 
every day working on flat fielding techniques.  Its that  important.
 
 
Clear Skies
Gary
 
 



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