#21  
Old 04-01-2011, 11:11 AM
TrevorW
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Join Date: Aug 2006
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Based on the calculator as these dust motes are around 200 pixels in diameter with a 7.8micron chip at f.9 then they are only aound 7mm from the ccd chip

Marc found the offending frame for the band across the top one of the last 6 minute subs I took

Surface dust on the primary mirror does not affect an image unless it is severely bad and then it would only diminish the amount of light being collected.

As you know the primary only reflects light along the path to a focal point where the image is then projected onto the sensor, motes on the primary would not appear in an image

Last edited by TrevorW; 05-01-2011 at 09:01 PM.
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