Originally posted by RuiC Try to find the 645 x K adapter manual and read carefully!! I have several 645 lenses and they have the very same FOV in the 35mm format as the K lenses counterpart.
Quote: The angle of view of 645 lens becomes smaller when the lens is mounted onto the 35mm camera, just the same as the 35mm camera lens with the same focal length.
Which is exactly what I said above. If you want the same FoV on a 35mm camera as you get when using the lens on a 645 camera you have to use a smaller focal length on the 35mm camera.
The 80-160mm, on 645 film, has a FoV of 39-20º. To get the same FoV on 35mm FF you need a 50-100mm lens...but the 645 80-160mm when used on 35mm FF would have a FoV of 30-15º, the same would be true of an 80-160mm lens designed for 35mm...