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Nick_3536
9-Jul-2007, 11:12
Is there a list or other resource that shows the thickness for the major screw in filter companies? Heliopan,B&W and Hoya? I mean the actual glass.

Thanks

Bob Gentile
9-Jul-2007, 13:19
Never seen that one. I've seen all kinds of specs -- filter factors, transmission curves for different wavelengths, thickness and thread pitch for the mounting rings... but never the thickness of the actual glass.

You've got me curious. Why do you ask?

Nick_3536
9-Jul-2007, 13:42
The price of Mamiya fisheyes has dropped so it's not much more money then the Kiev fisheyes once you add in everything. The problem is the Mamiya needs a rear filter in place. Of course the cheaper used lens are missing most of the filter set. Mamiya tells me the lens needs a filter 1.8mm thick.

John Schneider
9-Jul-2007, 14:49
Yep, if the filter is behind the lens, then it's in the optical path, and its thickness is important. I would take a micrometer down to a local camera store and carefully measure the thicknesses of various filter manufacturers' products. Make sure you carefully clean the anvils on the mike before you try this on a filter. Without a mike, I'm not sure of an easy and accurate way to measure this yourself.

C. D. Keth
10-Jul-2007, 14:32
You can mount any filter you like. The only difference is that you may have to have the lens mount moved a bit on a bench.