as has been said, input the actual focal length of the lens
as far as " crop " sensor:
The Crop Factor Unmasked
Field of View vs Focal Length on various formats
By PF Staff in Articles and Tips on Jul 23, 2014
Many of us have cameras with different sensor sizes; this raises the question of which lenses need to be used to get the same field of view on two different formats. Below we provide a table listing focal lengths with equivalent Field of View (FoV) across several sensor sizes. . . . .
Note that the focal length of a lens (say 50 mm) is an optical property of the lens and remains the same no matter what sensor size camera the lens is mounted on.
In other words, an smc Pentax-A 50mm F1.7 lens as shown to the right is a 50 mm lens when mounted on a Pentax Q7 (1/1.7 inch sensor size), on a Pentax K-3 (APS-C sensor size), or on a Pentax film SLR (aka 24 x 36 mm or full frame). The focal length does not change with the camera. But the field of view which the lens captures does change. And so does depth of field, but that is for another article. . . .
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The Crop Factor Unmasked - Articles and Tips | PentaxForums.com