Sorry if the title is misleading somehow, but what I found 75mm lens AF is not that snappy as 12-40 set on 40mm. I was kind of surprised that I could not lock focus sometimes on my E-M1 with this lens. True it was late at night with couple of bulbs lighting the room and TV was on. I tried my 12-40 in the same condition and it was much more responsive in that regard. Is it normal? My understanding that 75mm with f1.8 would be much better than f2.8 in situation like this. So who should I blame? Me, Oly75 or E-M1?