blonde wrote in post #5460349
thanks for the great feedback so far guys.
Wim- are you sure about that UV09 and above lenses?
Personally, I am, based on my own tests (5 copies, of which 3 prior to UV07, early last year, and two newer ones, UV07 and UV09, and comments from other people, four I know in my area who own 50Ls, and several comments from people here on POTN.
It was reported by one person that the focus shift may still exist, in the f/1.4-F/2.8 area at distances between 45 cm and ~1.2 or ~1.5 m, but apparently so small now as always to fall within DoF. Personally I found no proof of this. My own specimen (I kept the UV09 one) just works right, every time, every aperture, every distance, completely repeatable. The only variation I see is normal AF variation - all within focus however. Maybe not entirely normal, as it seems 99.9% repeatable on a tripod, with MLU and remote control. Since I also got a Katz Eye prism wedge focusing screen for the 40D, I did test the MF focus ability too: similar results so far, just very much slower 
. Note that my MF results show more spread than the AF results - that's good AF performance .
BTW, people who had their 50L calibrated and work correctly under all circumstances, report "electronic adjustments" were made, so I reckon something was done to the firmware of the lens to correct the problem.
With my particular specimen I found that AF hits right at the edge of DoF nearby, all the time, when doing focus tests, so seemingly slightly backfocusing all the time. This I found irritating at first, becaus eof th eidea of it, but in real life shooting I have really started to appreciate it; it looks to me now that that is how it should work with such a fast lens, especially considering the real size of the sensors. In real life it just gets it right all the time, provided of course I get things right myself in the first place - there will always be user error with such a fast lens used at very large apertures, especially with long shutter speeds, although I did manage a few sharp shots at 0.3" .
The bokeh is out of this world as well. And it is sharp. Only at F/1.2 it is not excellent, just very, very good, which of course may be caused by the very shallow DoF. And from F/1.4 it is sharper than any other 50 mm lens I have tested personally so far (4 50 F/1.4s, 1 50 F/1.8 Mk I and 4 Mk IIs, 1 50 CM, 1 Contax Zeiss Planar T* 50 F/1.4). I may test it against a Zuiko 50 F/1.4 as well, as soon as I get an adapter for it . I think I do know the outcome 
.
It does have some longitudinal CAs (the green and dark red at high contrast transitions in OOF areas) at very large apertures, just like the 85L, but a little less so. I did not manage to get it to flare, not even shooting with the (setting) sun in the frame in a high contrast environment, or lose contrast in difficult lighting situations. I haven't noticed any lateral CA so far, nor PF, but I used it mostly indoors so far, which may hide this. OTOH, the 85 F/1.8 showed PF both outdoors and indoors under the right circumstances, and I haven't seen any yet with my 50L. All in all, IMO, a very, very impressive piece of optics. As impressive as the 85L, just smaller and lighter .
I'll see if I can find a few pics that I can share, but since I am on the road again, that'll may take a few days if you don't mind.
Kind regards, Wim
