Originally posted by geekette Big G, so with full frame, I guess there isn't a crop factor and the older lenses work better with that body? I guess this makes sense if the photographer already has a large selection of older full frame 35mm slr lenses.
Unless you have a lot of experience with 35mm film photography, I recommend you forget you ever heard the words "crop factor". Those words generally only cause confusion and mean nothing to someone who doesn't have the reference point of 35mm film photography. (imho, of course
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You can use virtually any lens Pentax has ever made on a Pentax dslr, although some require an adapter. All of Pentax's bayonet mount lenses fit on Pentax dslrs without and adapter and work just fine.