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Old 13-01-2015, 03:48 PM
dave brock's Avatar
dave brock
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Join Date: Dec 2011
Location: hamilton nz
Posts: 83
A very quick calculation suggests you're going for close to f/14. Is that right? You might want to check the 'focus' by wetting the mirror and reflecting the sun as a back up to your bar and screw. It may be hard to get repeatable measurements on a 0.8mm sag with a 1mm/turn screw.
Remember, sun test will give focal length, not RoC.

Dave
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