i'm hoping to get a prime 50mm 1.8 but i'm unsure of what i should be looking for when buying a lens brand new from shop or 2nd hand from csers.
i read about alignment but what does it really mean?
besides alignment are there any other stuff i should look out for? should i snap some photos and view them in my 2.5" lcd? or should i just try out the AF and MF?