OK to use lens adapters?

[EidolonFilms]

A 50mm on a "1.0 crop" camera, and a 25mm on a "2.0 crop" camera, when shot side-by-side at the exact same distance towards the exact same subject, will result in exactly the same pictures (in terms of field of view and perspective). But there will be a difference in the depth of field; you would have to account for the DOF difference inherent in the focal length difference. So open up the f-stop 2 stops on the "2.0 crop" camera, or stop down the f-stop on the "1.0 crop" camera, and you'll have absolutely identical images from both cameras.

Yes this makes sense. I think what I was trying to get at is that on a 4/3 camera you would still want to have both the 25 and 50mm lenses. Just got confused in the whole crop factor thing.