Wonder is there a so-call SLR lens term?
Anyway if we mount a SLR lens on DSLR (450d), the focal length we need to multiply by 1.6 right? So if i have a Vivitar 70-210/2.8-4 APO, if I mount in on my 450d, it will become ~110-330mm lens? What about the aperture, does it remains?
As the Vivitar 70-210/2.8-4 APO is attacked by fungus, do you think its good to send for cleaning or buy a new lens better?