Thiking about the A57, can I adapt old lenses like vivitar, konica hexanon, takumar etc.?

You absolutely can with an adapter. It just depends on which mount you want to use. Alot of folks seem to prefer the M42 adapter because there's no extra glass in the adapter to take away from the IQ of the lens, but I have a cheap MD/MC mount adapter with glass in it and it seems to perform pretty well even with the lightly regarded Minolta 50 f/2.





Cheers!!