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08-12-2009, 10:23 PM   #1
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Medium format lenses

The lenses for 645 or 6x7 formats will work with Pentax K100D/K20D or K-7? If they work what will be the focal length multiplication?


08-12-2009, 10:32 PM   #2
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Will work with appropriate adapter and limited functionality. Focal length is a physical parameter and will behave the same as with any optical device (lens). So 1.5 times the real value (shown on lens) it's equivalent will be in therms of FF fov.
08-12-2009, 10:33 PM   #3
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There are adapters, both 3rd party and Pentax genuine ones, not cheap though. Here's a link for genuine 645-k adapter.

The multiplication is the same 1.5x, focal length is focal length - that won't change with format. It's just with medium format, say, a 50mm lens is a wide angle lens, 30mm is a fish-eye. On the contrary, same 50mm on digital is a short telephoto, and a 30mm is kinda like a normal lens.
08-12-2009, 11:54 PM   #4
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Thanks for the replies and the link.



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