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Old 12-10-2015, 10:09 PM
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alpal
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Join Date: Jan 2012
Location: Melbourne
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Quote:
Originally Posted by Shiraz View Post
there are a few apertures down that train that could be limiting the illumination at the corners with an f4 light cone. However, I think that 30% reduction should still be quite manageable with flat fielding - after doing this, the main effect will be a slight drop in SNR in the corners and maybe a bit of extra diffraction around bright stars - but so what? All it means is that you have an 8.5 inch scope in the corners and a 10 inch one in the centre of the field. Even the super scope designers accept significant vignetting http://planewave.com/wp-content/uplo...-spot-size.pdf

the RCC1 is the only CC I know of that will accommodate that length of image train.

Thanks Ray,
Yes - you're right -
I can still have a lot of fun with this telescope as is.
If I put a galaxy in the middle & then crop the frame
it would make no difference.

cheers
Allan
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