If I use a Mamiya M645 lens on my Nikon 35mm body with and adapter, how do I figure to focal length?
A 150mm M645 lens is what when placed on the 35mm body? The focal length is longer than my 35mm, 150mm lens.
If you read the lens focal length that is on the front of the lens (near the glass, written in a semicircular pattern) when it is on the Nikon, you will have your answer.
2F/2F
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