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Old 19-02-2008, 09:59 PM
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Peter Ward
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Peter Ward is offline
 
Join Date: Dec 2007
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Terry, interesting analysis, but I don't think it's quite so bad for the Canon for reasons I stated earlier.

The distributive property of multiplication over addition tells me summing colour channels will not change the CMOS result (just change it to a grey scale image in photoshop to see what it would look like)....but not filtering the CCD will drop a ND filter factor of at least 0.4, making it look brighter still..... Now *that* would have deserved me some flack!

Quote:
Originally Posted by CometGuy View Post

Peter, what I'd also be interested in though is seeing is a same exposure unfiltered STL11000 exposure versus a 5D with the red/green/blue channels combined in a Black and White image. I'd be interested in seeing difference in limiting magnitude of stars - have you got something along those lines?

Terry
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