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Old 07-03-2012, 10:04 AM
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philiphart (Phil Hart)
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Join Date: Jan 2007
Location: Melbourne
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oh.. and if you do find there is tilt, there's a 90% chance it's tilt of your sensor rather than tilt in the lens optics. you should be able to find out by rotating the lens relative to sensor and see whether the problem area shifts or not.

the KAF8300 sensor in my QHY9 was tilted.. tolerance spec is +/-0.25mm which is *enormous* compared to tolerance at f1.2. unless SBIG specifically calibrate the sensor in your 8300 then you could easily be dealing with same problem. good chance they can't calibrate to the required tolerance anyway. at f3 you might stand a chance.

Phil
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