Originally posted by Winder I used the 135L for years which is an F/2 lens. To answer your question I have used it in portraiture. Have you ever shot portraiture? Ever hear of the Sony (Minolta) 135mm STF? That lens was built specifically for portraiture. I'm not sure why you think there are so few 135mm lenses in production.
I agree but are we talking about 135 f/1.8 on aps-c, or FF?
I use the 180 f/2.8 on FF all the time for 'portraiture', and it's equivalent to about a 120mm f/1.8 on aps-c - so 135 f/1.8 on aps-c is usable for that purpose, I would say, even wide open. Heck, 135 1.8 is great on FF for portraiture - it's generally used for 'longer' portraits but it works fine.
180 f/2.8 == 120 f/1.8 apsc: