Thread: Taking Flats
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Old 31-10-2010, 06:05 PM
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Octane (Humayun)
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Join Date: Dec 2005
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Because if the telescope is not at the same focus point as when you took your image, then, any aberrations such as dust bunnies, fibres on the optics, etc., will either be smaller than when you imaged, or larger.

You need to take flats at the same camera angle orientation and focus distance to ensure any anomalies are removed in calibration.

H
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