Is focus issue with 50mm 1,2 a real problem ?

I really want the 50 mm 1,2 - but I am afraid of getting disapointed because of all the negative things of the "bad focus up to 3 meters or about 9 feet - and very often backfocus in this area" and rthings like that, So if u who have the 50 mm 1,2 could tell me if and how this is a problem i would be very grateful to u all.

Dude, practice makes a master! at F1.4 using a 30D the DOF at 3m should be only 10cm (16cm on FF) front and back, but a minute shake will blur the shot. do a focusing test on the lens. If it fails send it to have it repaired. That is all.

http://www.dofmaster.c​om/doftable.html

silvex wrote in post #4239854
Dude, practice makes a master! at F1.4 using a 30D the DOF at 3m should be only 10cm (16cm on FF) front and back, but a minute shake will blur the shot. do a focusing test on the lens. If it fails send it to have it repaired. That is all.

http://www.dofmaster.c​om/doftable.html

The backfocus issue with the 50/1.2 is not "repairable", it's a characteristic of the lens design Canon used for this lens. It's most pronounced around f/2.8 or so and then partly goes away as you stop down because of the increased DOF. Shooting at or near wide open is no problem and some say if you use an off-center focus point for short distances AF works better.

It's hearsay as I can't talk from my own experience - I decided to skip this lens, I don't like to have to think about compensating for a focusing error which is both distance and aperture dependant. If Canon releases a 50/1.2 II some day I'll buy one.

FretNoMore wrote in post #4240841
The backfocus issue with the 50/1.2 is not "repairable", it's a characteristic of the lens design Canon used for this lens. It's most pronounced around f/2.8 or so and then partly goes away as you stop down because of the increased DOF. Shooting at or near wide open is no problem and some say if you use an off-center focus point for short distances AF works better.

It's hearsay as I can't talk from my own experience - I decided to skip this lens, I don't like to have to think about compensating for a focusing error which is both distance and aperture dependant. If Canon releases a 50/1.2 II some day I'll buy one.

Clear and rational conclusion. - but . its a pitty Canon dont make a 50mm lens thats sharp and consitent in focusing ,
I agree - buing an expensive lense and then have too compromise all the time ...
My be I am wrong . but dont think its worth it this time.
Pitty again

It is a pitty. I was set on this lens until i began to read about that issue. I think I will just wait for the second version to come out.

I actually have the lens and am quite happy with it. My lens has the focus issue but it does not affect shots much beyond 3 feet. I have read of some having the issue out to 6 feet or so. In my case the problem rarely affects real world shots. If you shoot it wide open or nearly wide open the focus shift is a non-issue at any distance.
If you think you might want the lens, I would purchase from a good merchant with generous return/exchange period. That way if you find focus shift is a big problem for you, you can return the lens.

Here are a couple of snaps with the lens...

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It's focus accuracy and low light ability are fantastic. The focus drift never really affected my day to day shooting. I didn't like sharpness wide open.
Buy one second hand

mebailey wrote in post #4242043
That way if you find focus shift is a big problem for you, you can return the lens.

What exactly is the "focus shift" problem with the 50 f/1.2 L ?

I don't have the exact explanation but I think it has to do with an optical problem of focusing a fast lens at short distances, basically how well the lens is compensated for spherical abberation. When stopped down from wide open this abberation shows up more and it affects where the best focus is in the image, in effect shifting the sharpest plane a bit. As you stop down more this is then masked by increased DOF until it's no longer visible. So, the camera focuses the image with the lens wide open but when the aperture is then closed a bit to take the picture the sharpest focal plane is no longer at exactly the same distance. It has to do with the lens design, the 50/1.2 is I understand a simpler design than for instance the 85/1.2 which has a floating lens element to better compensate for this.

mebailey wrote in post #4242043
I actually have the lens and am quite happy with it. My lens has the focus issue but it does not affect shots much beyond 3 feet. I have read of some having the issue out to 6 feet or so. In my case the problem rarely affects real world shots. If you shoot it wide open or nearly wide open the focus shift is a non-issue at any distance.
If you think you might want the lens, I would purchase from a good merchant with generous return/exchange period. That way if you find focus shift is a big problem for you, you can return the lens.

Here are a couple of snaps with the lens...

Nice shots

roli_bark wrote in post #4268175
What exactly is the "focus shift" problem with the 50 f/1.2 L ?

Its difficult to deal with since those on the board cant agree if there is a problem and if there is a problem what it actually is. Canon's position is that there is no problem (at least that they have admitted).

I think the problem is inherent in their lens design. Iam not an expert by a long shot but know compromises have to be made to construct super fast lenses unless the sky is the limit on expense. One of the problems with fast optics can be focus shift which Fretnomore explained well above. My understanding is that in these fast lenses DOF can move backward as you close down the aperature unless you can correct it with a floating element (which I believe the 85L has). Since all focusing is done wide open then the lens closes down at the moment of shooting, the image appears in focus in the VF (whether you use AF or manual focus). Then when you snap the photo and the lens closes to your selected aperture (which we assume for this explanation is not f/1.2) then the DOF moves backwards and you get an OOF shot. It only happens at intermediate fs say f/2-4 and at close range because at higher fs and longer ranges the increasing size of the DOF masks the anomaly. Canon should have opted for a floating element but it may have raised the cost beyond what they thought they could sell the lens for. Remember, this all is only a hunch of what Canon customers think is wrong with the lens. It may not be right. But there is something wrong with the lens.

Sorry about the basic explaination, I really can't explain any of the optical the theory. I hope that is somewhat helpful. I did not mean to ignore your question for so long. I just saw it today.

G35Driver wrote in post #4335564
Nice shots

Thanks. I really do like the lens. When you play to its strengths the results can be very good. Its just that many feel at this price point you shouldnt need work-arounds...

Since we have resurrected this focus shift thread, some of you may be interested in something I noticed a few days ago. Check out this thread if you have not seen already.
https://photography-on-the.net/forum/showthre​ad.php?t=407604

It is certainly more than POTN folks who think there is a problem here...several other forums have had similar threads...there's even a petition being raised to try to force Canon to correct the problem.

I bought mine knowing that there were issues that needed to be worked around and accepted that it was not perfect throughout its spectrum. I have deliberately refrained from testing it and simply used it for shots......result...no problems seen. I'm sure that I could reproduce the problem given everything I've read that's been written but I have nothing to gain until the fateful day that I inadvertently use it at f/2 focussed at about 1 metre.

I don't mean to knock others who are disappointed with the lens...they have every right to expect a faultless piece of glass if that's what they think they paid for. I, on the other hand, knew I was buying a flawed gem.

Bob

Canon Bob wrote in post #4335830
It is certainly more than POTN folks who think there is a problem here...several other forums have had similar threads...there's even a petition being raised to try to force Canon to correct the problem.
Bob

You are right.