If your 50mm f/1.4 has AF accuracy problems you can send it to be calibrated by Canon and free of charge if it is under warranty.

However a lot of people complain about the AF accuracy of f/1.0, f/1.4, f/1.8 lenses and in reality is bad technique from part of the user, at f/1.4 your DOF is so thin that the slightest movement you do after acquiring focus with the AF system will result in bad results.

--
Think before you shoot!

Yeah no, I tested it on a tripod and calibrating doesn't help, since I already tried that with Micro-AF-adjustment.

The problem is not only, that my example is focusing wrong depending on focusing distance (at far distances it front-focuses and at near-distances it back-focuses).

The problem is, that there's a huge focus shift, when you stop down from f/1.4 to f/8. So if the AF sets the focus correctly for f/1.4, then closes the aperture to f/8, the picture will be out of focus.

I'm not using the lens at apertures below f/2.8 most of the time anyway, it's too soft there. The problems however are still there, even at higher apertures than f/2.8.

--
House is the audio equivalent of Braille.

"there's a huge focus shift, when you stop down from f/1.4 to f/8. So if the AF sets the focus correctly for f/1.4, then closes the aperture to f/8, the picture will be out of focus."

Sounds like the lens may be decentered - unusual but not totally unheard of. That's a manufacturer's defect, so if the lens is still under warranty, it should be returned for a new copy.

--
"They who would give up an essential liberty for temporary security, deserve neither liberty or security" - Benjamin Franklin

I don't think it has to do with being decentered.

It's the problem mentioned here: [link]

I think this is a property of the lenses used. "Better" glass would show less of this effect.

--
House is the audio equivalent of Braille.

micro adjustment is different than the calibration Canon (or any other manufacturer) will do since they will run tests and check out if it is:
1)A mechanical defect.

2)If it the lens calibration was poorly done in the factory and doesn´t meets the standard.

3)Or any other reason that might affect its performance.

Keep in mind that micro adjustment is only going to solve some types of front or back focusing issues, others require to take look at the lens, remember that you are telling the camera to back or front adjust the focus to some degree but if there´s something wrong mechanically then it won´t do any effect.

My recommendation is still the same send it to Canon to be checked out, at f/1.4 the lens will be always kinda (not that much) soft, but it should improve (looking good) at around f/2.0 and be insanely great from f/2.8 onwards.

--
Think before you shoot!

What eyeballman says is one of many mechanical problems that could be affecting the lens.

I have used a properly calibrated 50mm f/1.4 and to tell you the truth f/1.4 looked kinda soft but really very acceptable, and from there it gets better fast.

--
Think before you shoot!

I don't know how much tests you did with your lens. I get ok pictures sometimes, too.

--
House is the audio equivalent of Braille.

I don't know where you get your informations. Here in Europe they don't do those things you mentioned in 2) or 3). They will just put it on a fixed mount with a fixed calibration target and calibrate it for that fixed distance.

I'm pretty sure they can't even fix the focus-shift problem, since it is a physical problem.

--
House is the audio equivalent of Braille.

EF-S 10-22, does exactly what its meant to.
EF-S 17-55 f/2.8 IS, can't fault this either.
EF 70-200 F4, can't fault either, I'd like the IS version but I can't blame that on the lens! You can't blame a lens for only being F4, buy the f/2.8 if it isn't good enough. It does what its designed to do perfectly.

EF 85mm f/1.8, possibly my most satisfying lens but sadly had to sell. Oh, it got filled with dust, something that the 17-55 is apparently meant to do, never mind.

EF 50mm f/1.8, most dissatisfying but can't complain after getting one so damn cheap.

--
Pete-EOS | 350Dlovers | Waterscapes-Club

Thank you!

--
House is the audio equivalent of Braille.