Hi there. Im looking to get a135 2.8 second hand. The ai ones are a bit above my budget atm. But I've seen an converted NON ai for a good price and nice condition.
I just would like to know Is there any difference in optics quality etc between the ai and non ai?
Is it just different fitting. That all?
Anything else I should maybe check before deciding to go for it?
Thanks for reading 

