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 p.3 #11 · 50L or 35L on a 5D Mark III | |
Lars Johnsson wrote:
Maybe some people are not used to work with very fast f/1,2 lenses with very small DOF. Often they have never used such a fast lens before. Others maybe don't know or understand about the focus shift at close distance. Others just recompose for portrait as they did with their f/2,8 lenses before. There can be a lot of reasons.......
I agree with most of this Lars. I am quite used to shooting f/1.4 with my 35L, but it's more wide-angle so it's more forgiving.
The way I tested the 50L, however, rules out focus shift (I shot @ f/1.2 all the time) and recompose error (I didn't recompose). I did the following:
- I was in a camera store, it was inside, only tungsten lighting (no windows)
- First I tested the 5Dclassic + 50L combo using a Lens Align unit, camera on a tripod. I shot f/1.2-1.4-1.6-1.8-2.0-2.2-2.5-2.8-3.2-3.5-4.0 and the focus shift was quite apparent.
- By coincidence, the combo was tack sharp on the LensAlign.
- Then I tested to mimic shooting an indoor wedding ceremony @f/1.2:
- Camera set to focus with exposure button (no back button focus)
- f/1.2
- shutter speed 1/250 or faster (I have a steady hand)
- fired 200 frames at various subjects: shelves with photographic equipment, desk clercs, cameras, studio lights, etc.
- range varying from 1.5m~5m
- No focus/recompose, just focus and quickly release shutter, to prevent distance shift by me or by the subject
- 20% shots perfectly in focus, 10% barely in focus, 70% unuseable
Repeated the same steps with 5DmkIII.
- I needed -8 MA to get it sharp on the Lens Align
- 80% shots perfectly in focus, 10% barely in focus, 10% OOF, but useable at 4x6
So based upon my own testing, the AF problem with the 5Dclassic/50L is real.
Just to be sure I took my 5Dclassic + 35L and repeated the same test for about 50frames, mostly of the same subjects. Shot @f/1.4 only, got 90% perfectly focused shots, 10% slightly OOF.
Of course a 1 series body with better AF will help you. But it will help other lenses like the 24L,35L, 85L also. It's not like it only help the AF with the 50L. It's not like the 1DsII has some magic AF that works especially good with the 50L and not with other lenses
My 35L is as good as it gets, but of course any lens will benefit from better AF. I don't know what it is with the 50L, but what about this:
I would be willing to get a 1DsII solely for being able to shoot the 50L. There is no other reason I would need one, because my 5Dclassic works magic with all of my lenses. This may sound irrational, but I know a 5DmkIII will be excellent with the 50L, and so may the 1DsII.
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