• UPDATE



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400mm f/4 DO II + 2xTC III + FoCal AFMA

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AlanF

AlanF

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Aug 16, 2012
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I find a large discrepancy between red and green channels AFMA from FoCal for the 400mm DO II and 2xTC III. It's fine for the bare lens and also with the 1.4xTC. The 2xTC III on the 300mm f/2.8 II gives perfect agreement between green and red channels so it's not the TC.

Has anyone else calibrated the DO II lens with FoCal and found this discrepancy?
 
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