Can anyone share their bookmark for the original thread on the 50L? I've already done the Google thang, but I must not be describing the subject correctly. TIA
Near the very end of that thread, this post was made by hahr:
I asked chuck westfall for an update last week and this was his esponse:
"Technical discussions about the EF50mm f/1.2L USM are continuing to occur between Canon USA and Canon Inc.. The matter is not resolved yet, but it is most certainly not being ignored. Unfortunately, I can't say much more about it until there is an official conclusion."
i understand the legal reasons behind chuck's somewhat vague commentary about this lens and am glad to hear that the wheels are turning.
ironically enough, by the time canon finds a fix for this lens i may not even want one anymore. i might just get a 45 TS-E to use as my normal lens and call it a done deal. ...Show more →
Did Canon ever make a determination? "Fixing" the 50L would involve Canon putting a floating element into it am I right?
I believe Canon ignored the problem, and they got lucky enough that the complaints went away (most likely focused on 1DIII problems).
That said, many users didn't notice the issue, and the focus shift became almost more of a quirk in the design which only affected some but not everyone because of the ways different people shoot. When I had one, it had no effect on me.
I tried a 50L F1.2 for 3rd time about 3 months ago; it was the worst of the 3 and it went right back to B&H. I've been curious see if new 1D3 and 1Ds3 owners are having better results since the 1-series has the new focus engine.
Did Canon ever make a determination? "Fixing" the 50L would involve Canon putting a floating element into it am I right?
They certainly did.....long time ago......to let equipment deficiencies like this one ride silently. If we live long enough to see a successor to the lens, in it they might address that aperture caused defocus anomaly.
What I find puzzling is the apparent lack of user unanimity on the backfocus problem. Does that mean that the extent of the problem may vary in a major way and/or some folks have not looked for it/observed it (yet) ?
However, in our imperfect world, I still consider that lens to be very good.
They certainly did.....long time ago......to let equipment deficiencies like this one ride silently. If we live long enough to see a successor to the lens, in it they might address that aperture caused defocus anomaly.
The "aperture caused defocus anomaly".
Couldn't the anomaly be solved with a floating element?
I think it is a variety of factors, sample variation AND the technique of the people shooting. If you're shooting wide open it's not so bad. If you're shooting from a tripod, the focusing flaw is very apparent. Some people wobble or make minute movements when shooting and may luckily hit an area of acceptable focus. Some people just don't notice when the area of focus is not what they intended. I've tried two copies, gave up, and now have the original 50L. The original 50L focuses perfectly and has a wonderful 3D feel to it, love it so much more than the 50mm f/1.2L
PetKal wrote:
They certainly did.....long time ago......to let equipment deficiencies like this one ride silently. If we live long enough to see a successor to the lens, in it they might address that aperture caused defocus anomaly.
What I find puzzling is the apparent lack of user unanimity on the backfocus problem. Does that mean that the extent of the problem may vary in a major way and/or some folks have not looked for it/observed it (yet) ?
However, in our imperfect world, I still consider that lens to be very good.
Yes, mine also backfocus at f stop smaller than f2 when close focusing(under 1.25 meters or 4 feet). But since I always use apertures bigger than f2, it does not affect me that much.
Hey, the Noctilux also backfocus because it has the same double Gaussian design than the 50L (and cannot focus closer than 0.9 meters), with the same design choices. If Canon can include a floating element and retain the same bokeh for their Mk II, I will buy it!
If you look through all of the threads on the 50L you'll find that a bunch of us wrote Chuck last May and got the response back that an announcement was expected from Canon in the near future. Follow-ups with Chuch haven't gone anywhere. Here was his response:
"Canon Inc. is definitely aware of the claims concerning the AF accuracy of the EF50/1.2L USM. They've been investigating for the past couple of months, and I am told that there will be some kind of public announcement forthcoming in the near future. Stay tuned, and thanks for using Canon equipment!" - email from Chuck Westfall 5/24/2007
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.
Mine is still has the anomaly with new 1DsIII. Iam pretty sure its a design flaw or "compromise" with the lens. I can ameliorate it some with the micro AF adjustment but cannot get it perfect like with other lenses in my collection. I still use and typically get good results with the lens...
I don't own this lens yet but had the opportunity to use a copy for a day on my 5D and plan to buy it in the future. I'm in the group that knows about the focus shift and is okay with it as a compromise considering all else that this lens delivers. Correct me if I am wrong, but the only 50mm lens of this speed which does incorporate a floating element is the 55mm f/1.2L FD. That's not to say Canon shouldn't have included one, but I think it's unlikely that they will re-engineer the lens. I'm guessing that a new design incorporating a floating element to address focus shift would satisfy a small group of prospective buyers while upsetting a larger group of current owners. Likely Canon will get around to doing it, just not for a number of years.
An alternate solution, which Joe Mama proposed some time ago in the DPReview forums, and which I recently espoused in a blog post here, would be for Canon to release a software fix. Konica took this approach in 1993 with the Hexar AF. They left a significant degree of spherical aberration uncorrected, apparently to enhance the bokeh and wide open performance of the lens, and had the in-camera computer correct the autofocus for focus shift in an aperture and subject distance-dependent manner. If Konica could do that with existing technology 15 years ago, shouldn't Canon be able to do it in firmware today?
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.
I did send it in and Canon said that it's "within specs".
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.
i gave up and bought an 85/1.2L II instead. having gone through four bad copies of the 50/1.2L to date, i won't consider one again until a mkII version has been announced -- if that ever happens.
what was once vaporware surprised many in its announcement, excited many in its release, and disappointed many upon its delivery. this is one lens that canon never should have let go to market in its current incarnation.
oh well. the best thing to do is to pick another lens and move on.
