I've just bought the 50mm F1.2L and can soundly say it's an awesome lens. Strangely, I feel compelled to post some 'facts' given all the negative press. Just to clear it up, I'm not a pixel peeper but did run a few tests in store before buying, purely to avoid getting a dud. I decided to go for the L model over the F1.4 because I wanted something that will last. All the F1.4 users I know say that although the lens is tack sharp, it's not robust at all. In terms of my style, I love 50mm, so for me the investment was worth it
First of all the negatives:
Not especially especially sharp from 1.2-1.8 (but gets a lot better in
natural light vs indoor light). More importantly I would use these settings
Visible purple fringing at above apertures - boo!
I have tried to recreate the focus shift issue and was only able to get a rare few that were maybe slightly out by 1mm or so (incidently this was on distances less than about 2.5ft and F1.6-F4) - no worse or better than my 24-105mm F4 so I'm more than happy as the latter is a cracking lens. Autofocus-wise, this lens is up there (of the ones I have tried to date...)
Len's element moves up and down the barrel and is naked to dust and moisture - need filter!
Now the good:
Sharp at F2 and tack sharp by F2.8
Sharper than the 24-105mm at F/4 and nothing between them by F/5.6
On my 5D2, focusing is AT LEAST as fast as the 24-105mm and never hunts like my 24-105mm does in low contrast/light.
The colours seem fuller and punchier than my 24-105mm
Bokeh is beautiful
Build, size and feel is awesome
I am a bit of consumer from hell and usually take equipment back to the store (I've had bad backfocusing issues with Tamron and Sigma lens). None of that this time.
What a nice surprise this lens has turned out to be