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Old 20-06-2014, 10:24 AM
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cometcatcher (Kevin)
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Join Date: Jan 2005
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Quote:
Originally Posted by raymo View Post
Don't forget that your subs will have to be
twice as long.
For a 2X converter, exposures have to be 4 times as long. A 1.5X converter would be twice as long. For instance a 2X converter would take an F5 optical system to F10.
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