Originally posted by Michaelina2 My 28mm adventure took this path: M42 28/2.8 --> M 28/2.0 --> F 28/2.8... If I had it to do over again, I'd go for the F 28/2.8 and tip-toe past the temptation to fuss with the rest. Don't read this wrong... the others are excellent... even dazzling... I have no regrets, but the F version - for the money - is the most versatile and satisfying to use ... read the reviews in this forum... It took some time to find one, but the wait was worth it.
Cheers...
While I don't disagree that perhaps an AF lens would be worthwhile, I suspect the OP might be looking for something older and less expensive.
If you add up all my 28mm lenses, the total cost is something like $100, that is for the M28/2.8, the sigma mini wide 28/2.8(KA mount), an M42 Vivitar 28/2.5, a K mount Vivitar 28/2.5, the Tamron 28/2.5 in KA mount, and A Kiron 28/2.
If yuou look a lot of these lenses can be had cheap.
As I said the only regret was tie sigma mini wide, due to the lateral CA (i ran a thread on CA removal in different software, using this lens for the sample image) but i got it due to the KA mount.
The Kiron 28/2 is a nice lens, but I got mine cheap due to stuck aperture blades, which are problematic on the Kiron and vivitar (by kiron) 24 and 28mm lenses from the early 1980's.
The lenses that impress the most for the cost (~$10 each) are the vivitar 28/2.5 lenses.
My tamron is OK but, does not really do anything for me. Again it only cost about $15 so no loss.
The M28/2.8 is a very nice lens, but it will cost more, i got mine along with an M135/2.5 as a pair for $105. Lets say 50-60 is a good price for one.