It is a shame that the 50 has had this problem. I always knew that when Canon made the 50 f/1.2L that I would buy it without a doubt. Canon has proven to me recently that I should not trust things when they first come out, so I wisely, unfortunately, waited for the early adopters to try it. I still follow this len because I keep hoping that something better will happen with it, and I will purchase one. Canon hasn't given me a reason to do this.
Canon seems to be making more and more mistakes lately. Hopefully, 2008 will be a better year.
stanj wrote:
To me it's the combination of focus shift and sheer softness ("dreamy" look) that makes me love/hate this lens (the hate part). No I am not obsessed with sharpness, I'd buy macro lenses if I were. But the 35L and 85L are far sharper wide open, so the 50L - the "easiest" focal length in 35mm format - should be able to be just as good. The 50L photos are simply blurry wide open, compared to the 24L, 35L and 85L which I also have.
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I'm also disappointed with this lens (on my 1Ds2) because of its utter inconsistency at acquiring focus at close quarters. I like the "dreamy look" mentioned above, but would like to be able to count on this lens being able to reliably focus on an assigned focus point, important for me in portraiture. I find that the 85L v1 and the 35L are far more predictable when shooting wide open, given the constraints of limited DOF. Wherever focus may fall, my copy of the lens is very sharp, it is just impossible to predict where it will be. Not a good thing, at least to me. I find this situation very surprising, albeit unpleasantly so.
Roy Pertchik wrote:
Yes, asabet, many, many, many people, in many threads, here and elsewhere, have been asking for a simple software fix. It could be download able to camera firmware, possibly by users, but barring that, it could easily be done as a tweak to the lens firmware installed at a Canon service center. That's where it gets expensive...all those lenses mailed back an forth.
I have complied a petition to Canon to fix this, with FM's who ask to participate and provide their names and e-mail addresses. If you would like in, PM me with your name and e-mail address.
Hi Roy, just sent you a PM with my name and email.
Can you explain the nature of the data and/or computations needed in a firmware fix for spherical aberrations ie focus shift (the type usually dealt with by a floating element)? I want to make certain we are discussing the same "issue".
A software fix for this doesn't seem simple (although I must admit nothing in photogrpahy seems very simple to me). Somewhere a computation has to be made relative to how much shift is going on at any given f-stop and agreed upon increment of distance. Assuming my previous statement is correct, would the current firmware chip on a 50L have the capacity to execute such computations beyond what it already does, or at the very least have enough space to store the results needed from a computation made off-chip?
BrianP wrote:
It is a shame that the 50 has had this problem. I always knew that when Canon made the 50 f/1.2L that I would buy it without a doubt. Canon has proven to me recently that I should not trust things when they first come out, so I wisely, unfortunately, waited for the early adopters to try it. I still follow this len because I keep hoping that something better will happen with it, and I will purchase one. Canon hasn't given me a reason to do this.
Canon seems to be making more and more mistakes lately. Hopefully, 2008 will be a better year....Show more →
One could say the 50mm f1.2L does not have a problem. For a lens without the typical correction for spherical aberration, focus shift is to be expected - noticeably at close distances.
Once we adjust our mindset away from focusing on the symptoms (so to speak ), I think we can make headway toward a resolution with Canon.
What I mean is, as long as folks keep sending their 50Ls back to Canon complaining of various focus shift problems, Canon can keep sending them back and saying the lens is operating within spec (which it is). When folks start telling execs like Chuck Westfall they want a floating element system or a software correction for spherical aberration such as those mentioned by Amin and Roy, we allow Canon less room to wiggle because we are resetting the parameters of our requests.
Of course, those of us who do not care for the design may have to deal with the fact that there could be photogs out there who understand and prefer the design. (This group hasn't been very vocal though.)
Erik, with your four bad copies, are you referring to focus shift at close range (design compromise) or something related to bad QC, ie different problems with each copy?
rfkiii wrote:
Hi Roy, just sent you a PM with my name and email.
Can you explain the nature of the data and/or computations needed in a firmware fix for spherical aberrations ie focus shift (the type usually dealt with by a floating element)? .
Hi rfkii,
I added you to the petition, thanks.
If I understand, the lens has a look up table which it uses to turn the lens in response to the camera doing the computation. Camera reads the phase shift of the incoming blurry image, camera sends lens a signal of how far away to focus and aperture setting, lens looks up how far to turn per the signal, and turns focus and sets aperture. I think it's just a matter of editing the look up table to turn a different amount for the different aperture. There is a lot of speculation on my part here, you are right, the lens may not have capacity to respond differently depending on aperture.
Roy Pertchik wrote:
I compiled a list of names and e-mail addresses submitted to me by FM'ers for a petition to Canon to do something. I got about 50 or so volunteers and sent an e-mail to Chuck via another website where he participates. I sent it about a month or so ago, but i have gotten no reply. Does anybody have an e-mail address I should ust to submit this petition? You can PM me. Also, if you want me to add your name and e-mail address to the list, PM me as well.
I sent Chuck Westfall a direct email on the 50L too (since I believe the more customer complaint Canon sees, the more pressure they feel). I won't reprint Chuck's response verbatim since I'd like for him to respond to my absentee 5D mkII email.
Basically, he said he has tried his best to convey to Japan some of Canon's customers' concerns and frustrations. Note the use of the word: some. He suggested that I contact the Service Department since it is they who have the perogative to handle such complaints as they see fit.
Since I returned the lens, I do not know what level of standing I would have at the Service Department. Once, when I presented the Service Department with a problem regarding the dim output of my 5D's viewfinder information bar in bright sunlight, they couldn't fix it, declared it "within spec" and suggested that if I were still dissatified with the brightness level I should contact Customer Service to "register a complaint".
So, I sent Canon USA Customer Service a message through the website regarding the 50L, the 5D mk??, and my dim viewfinder info bar.
rfkiii wrote:
So, I sent Canon USA Customer Service a message through the website regarding the 50L, the 5D mk??, and my dim viewfinder info bar.
I did the same after getting a similar reply from Chuck last year. Got a reply back from customer service that there aren't any known issues with the lens and that I should send it to factory service for evaluation. Well it had already been there and back with a note of "in spec". At least I consider myself lucky that they didn't mess it up.
Chuck has not responded to my e-mail containing 50 FM signers of a petition for info on the 50 L focus shift issue. Shameful.
Roy, how about forwarding the same e-mail to his boss, cc. to the boss once removed as well, with a request to free up some of Westfall's time so that he may compose a reply.
Roy Pertchik wrote:
Sure! Can you provide names and e-mail addresses of said boss and uber-boss?
I'll try calling them tomorrow. Hopefully their org chart is not 'confidential".
If that was Canon Canada, I could do it off the cuff.
Google helps......all info posted by Canon USA for public edification........surely cheaper than long distance phone calls too.
Yoroku Adachi....Pres &CEO
William Reed,....Sen. VP Corp. Communications.
Now, Reed may not be Westfall's direct superior, however I'd expect him to be in his line management.
No one, or corporation, is perfect, and a business decision was obviously made in this case, but the more pressure one receives to be better is welcome by those that WANT to be better.
I agree westvleteren. Nobody is perfect, but I would expect Canon to have pulled the lens from the market until they solve the problems, and, also keep existing users updated. But none of this is happening. Many have invested hard earned money in Canon by buying this lens, and now sit with a defective product which you can't use well.
Evidently, I am one of the fortunate few who has a 50/1.2 that is not a "defective product." When I carefully test my 50/1.2, it exhibits focus shift (inherent, it seems, for fast 50s), but only at close ranges, and the depth of field never shifts beyond the focus point. In real world shooting, the focus shift is indiscernible. Otherwise, focus is accurate and relatively fast (perhaps slightly slower than my 24-105, but much faster than my 85/1.2 II), although the 50/1.2 is more sluggish and prone to hunting in low light than I expected. (This is on a 1Ds II.) In terms of sharpness, my 50/1.2 is about 1/2 stop less sharp than my 85/1.2 until about f/2-f/2.8. In other words, my 50/1.2 is about as sharp at f/1.6 as my 85/1.2 is at f/1.2. Beginning about f/2, those two lenses are, for all practical purposes, equally sharp. Setting sharpness aside, the image quality between my 85/1.2 and my 50/1.2 is very, very similar -- and that's a very good thing. So, overall, I am quite happy with my 50/1.2 -- the focus shift does not affect me, and while I slightly prefer the IQ of my 85, I more greatly prefer the angle of view of my 50.
By the way, I was one of those who corresponded last year with Chuck Westfall about the 50/1.2, and received the same response as has been reported. I followed up this year with various Canon service centers to see if there was any truth to the rumor that there has been a silent fix to the 50/1.2 (mine is an early model). If there has been a silent fix, the service centers are not disclosing it.
Somewhere a computation has to be made relative to how much shift is going on at any given f-stop and agreed upon increment of distance. Assuming my previous statement is correct, would the current firmware chip on a 50L have the capacity to execute such computations beyond what it already does, or at the very least have enough space to store the results needed from a computation made off-chip? 
