I just recently bought my first DSLR, a Canon Rebel t2i/550d. I use it mostly for video and it works wonderfully. I bought the kit lens with it, but I am looking to expand my lens collection. I found a set of old Minolta lenses from my dad, and I was wondering if I could use them on my new camera. The lenses are: a Sigma UC zoom 28-105 f4-5.6, a Minolta Maxxum zoom 70-210mm, a Minolta Maxxum zoom 28-58mm and a Kalimar 500mm lens. I know about the crop factor and that the auto focus won't work, but that does not bother me. Is there an adapter for Minolta AF/Sony to Canon EF mount? Any help is appreciated. Thanks!
It certainly looks like you can get the adapters - a quick check on ebay revealed this one.
Though I can't verify how good it is, etc...
There is different way to adapt lenses designed for one brand to fit another brand of DSLR.
If the flange focal distance of the lens brand is bigger than the one of the body, you can use a lens-less adapter ring (as an example Contax C/Y mount lenses on Canon)
Doing the same with shorter flange distance (as exemple Contax C/Y mount lenses on Nikon) has the effect that you lose the ability to focus at infinity. In such a case you can either:
Those three solutions share the main problem that you will lose the coupling between the lens and the body (Apart from in specific cases such as Contax N1 mount to Canon), which means you will have to focus manually and meter in AV mode stepping down the lens manually.
The usage of an adapter with a ring (as suggested by Mike) has the additional drawback that the additional adaptor (low-end quality) lens will, most of the time, cause bad optical performance. Note also that the distance scale (on the focussing ring of the lens) is no longer usable with an additional lense.
Usually this is enough to discourage the usage of lenses from one brand on another body except for some very good lenses (and only in the cases without additional lenses). See also the discussion on Bob Atkins' site
If you really want to use your lenses I suggest that you replace the lens mount. To see a step by step discussion here, although it doesn't seem easy.
Typically, lenses made for one brand of camera (or worse, one line within a brand) can't be used on another.