I'm having a bit of a hard time deciding between these two lenses - mainly for portrait use, but also for general photography - and was hoping to get some additional advice.
I already own an 85 f/1.8 USM, but do like working with a 100mm lens for tighter headshots. I actually already bought the 100 f/2.8 Macro USM and do like a lot about the lens, but also think that maybe 100 f/2 USM would be a better option. I'll be using this lens with my 5D MK3, by the way.
Things I like about the EF 100 f/2.8 Macro USM:
-solid construction; I like that it's longer and thus easier to hold in my hands
-seems to be very sharp and renders colors and detail beautifully - based on the short amount of time I used it
-macro capability - never had a macro lens before so this is very new and fun to me
Things I don't like so much:
-even though it's a f/2.8 lens, not all cross-type focus points are available on my 5D MK3 - instead of 41 cross-type points I only get a cluster of 21 in the center
-manual focus ring is WAY TOO fast at longer distances - took me forever to dial in good focus manually
-can't go lower than f2.8 - not a deal breaker, but it's nice to have an extra stop when needed
-I was also reading Ken Rockwell's review of the EF 100 f2.8L Macro, which optically is supposed to be the same or better than the non-L version, and at longer distances sharpness seems to suffer quite a bit compared to the 100 f/2. ( http://www.kenrockwell.com …es/100mm-f28-is.htm#sharp ). Overall he says the 100 f/2 is probably one of the sharpest Canon lenses, which I like.
Ideally I would have both of these, and maybe I will at some point, but for the time being - which one would you choose?