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Old 26-07-2019, 04:50 PM
benklerk
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benklerk is offline
 
Join Date: May 2008
Location: Katoomba
Posts: 220
Quote:
Originally Posted by Atmos View Post
You're actually at 85.8mm I'm afraid.
A 3mm filter adds 1/3rd to the optical back focus (subtracts from the mechanical).
61.5+20+5.3-1=85.8mm
You sure? I was told you add the filter thickness into the total backfocus.

If that is true do you know where I can pickup 3 m68 or m69 1mm extenders. It would save the hassle importing them.
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