I'm just starting out with DLSR photography - I recently purchased a Sony A230 with the kit lens (18mm - 55mm). I know that the lens mount is compatible with Minolta lenses. These lenses were originally designed for film SLR cameras, and I'm wondering what impact that will have when I go to use them with my camera. Some websites advertise lenses for a Minolta mount that have the ominous warning NOT FOR DIGITAL SLRs.
What am I getting myself into when I buy older film SLR lenses? I have heard that the effective length of the lens changes due to the different sizes of the image sensors, but how can I calculate this? Are any other lens specifications, like aperature size, that are changed? Will autofocus still work? Will my camera be able to read the lens? What would happen if I bought the lens that is linked above - would it really not work with my camera or give horrible results?