I currently have a 50/1.0L and would be interested if anyone has used both the 1.0 and the 1.2 and how they compare. I can't see getting ride of my 1.0 as there are just things it does wide open I can't see another lens doing but have considered adding the 1.2 if it's faster focusing and a bit sharper at 1.2.
ghuff wrote:
No, you really don't want to join the club. But thanks for posting these. My first lens could not pass this test wide open, and the second could pass at f/1.2 but rapidly started backfocusing at above f/1.2. So I am glad to see your results that show your lens can pass this test.
And yes, PLEASE try it on your 1D and let us know how it does.
I do see one possible difference though in your test shots versus mine. My test focus chart was flat for all of my tests. Both my lenses exhibited slight barrel distortion. In other words the "focus here" line was bent oppositely to yours...mine was convex (barrel)...but yours appears to be concave (pincushion). SO the big question is..... WAS your paper flat for this test? And if so, this pincushion distortion MAY be a sign of what correctly adjusted lens elements are supposed to do...since your lens does not seem to backfocus.
Interesting observation about barrel and pincushion distortion, and could very well be the key to the mystery. I'd love to see pics of your test shots to compare. The sides of the test chart was held down with weights on a flat surface to ensure "flatness". I stopped down to f/8 before I was convinced that there was no back-focusing. It was pretty late at night when I conducted the test, so I didn't really feel like conducting the same test on the 1D. I'll conduct the same test today using both bodies, run it through all aperatures, and post my findings.
This thread has surely piqued my curiousity to the point where I'm actually really looking for any sign of a defective lens. I'm just not understanding why so many of you guys are having these problems while some of us don't appear to be. Even with us having serial numbers so close in range. Gary, I've sent you PM.
ed, i'm glad to see that yours is working perfectly. my second copy is going back to the store but i'm not giving up. i plan to keep trying until i get a good one.
Double-check yours stopped down. Mine performed flawlessly at 1.2 (and also as Gary's)would backfocus as I stopped down. With each incremental stop down, it moved further and further back (and only seemed to do so at distances between 1.5 and 4 feet). Even refocusing did no good as Gary notes the lens focuses wide open. It doesn't happen all the time on mine either, just about 60% of the time, But I, as others didn't spend $1500 on a lens to guess if I got the shot. I wound up missing a critical shot at a wedding I shot last week as a result.
I also shot with my lens for approximately 2 weeks and didn't notice a thing, and for the few times I did shoot between 1.6 and F4.5, some were in focus, some not. It seems that 2.2 is the sour spot with my lens at least. Perhaps its a design flaw, perhaps not. Some possibly may have not noticed as they are all to thrilled with shooting wide open with their new lens. Who knows.
Thanks, Gary. I just finished conducting another tests with both cameras and will be posting my results shortly (I keep getting distracted by this Tornado Chaser show on National Geographic ).
ghuff wrote:
Yes, and it is being refocused...problem is the Canon system (and maybe others) focuses WHEN the lens is WIDE open. Then it only stops down to the selected stop when the shutter button is pressed, leading to the focus error. Understand?
...so if you focus manually and then use DOF preview to stop down, the problem will still appear, right?
johnastovall wrote:
I currently have a 50/1.0L and would be interested if anyone has used both the 1.0 and the 1.2 and how they compare. I can't see getting ride of my 1.0 as there are just things it does wide open I can't see another lens doing but have considered adding the 1.2 if it's faster focusing and a bit sharper at 1.2.
Any comparisons, observations?
John A. Stovall
Canon 20D and 5D with these Canon Lenses 400mm f/5.6L, 200mm f/2.8L, 180mm f/3.5L Macro,135mm f/2.0L, 85mm f/1.8, 50mm f/1.0L, 35mm f/1.4L, 24mm f1.4L, 16-35 f/2.8L, 24-70 f/2.8L, 70-200 f/4.0L, 70-200/2.8L IS, EF 1.4X II, Peleng 8mm f/3.5 and 580EX. Modified Holga 120N. CANCELED orders for Leica M8, ZM 21/2.8, 35/1.4 'Lux ASPH, 50/1.0 Nocti', 75/2.0 'Cron APO ...Show more →
Take the tons of money from your canceled Leica order and buy a 50 f1.2 and see
dinoadventures wrote:
...so if you focus manually and then use DOF preview to stop down, the problem will still appear, right?
Interesting idea for testing! Well...unfortunately I don't have a lens to test with now. The focus shift theory appeared about the time that I sent my last lens back to the dealer. Someone else with this problem and lens here on the forum may be willing to give this process a go, I'll bet.
I would guess that if you use the DOF preview and then focus manually, that the problem would go away...
dinoadventures wrote:
...so if you focus manually and then use DOF preview to stop down, the problem will still appear, right?
i just tested this and the backfocus issue does not appear when using the DOF preview button. i tried f/2, 2.8, 4, and 8. my copy will backfocus when stopped down in real-world shots.
weird.
-erik
Edited by flatdraft on Jan 21, 2007 at 12:25 PM GMT
ok, i ran the test again and here's what i found...
f/4 using AF will backfocus.
f/4 using DOF preview requires an MF adjustment to get proper focus.
it seems like i can get consistent results by using the DOF preview and adjusting focus as i see it. if i let the camera decide focus point then everything backfocuses, whether it be on AF or MF.
critical focus with this lens only works with the DOF preview and NOT trusting the focus confirmation light.
my lens is proving to be a much sharper copy than first thought. it's the focus communication system that needs to be sorted out.
I have shot two gymnastics meets with the 50 1.2L on an EOS-1D MkII and an EOS-5D and have been very happy with the lens performance from every aspect.
Its resistance to flare has kept me out of trouble in several circumstances, and I plan to give it the acid test at the University of Georgia next week.
I have been following the discussion on backfocusing with interest and puzzelment. After testing two 1.2L's from the UU1000 batch, I have encountered no backfocusing issues. In my resolution tests, I was using a 51 inch working distance, focused at f/1.2 and fired at various f/stops. Resolution results are shown here for the center of the image.
There is no going back for me. The more I use the lens, the happier I am. I have tested it for astrophotography, and it outperforms the 1.4 lens hands down as far as freedom from coma. I'll be putting the astrophotos in my revised review also.
I'll be interested in learning what the basis is for the backfocusing issues several of you are experiencing.
In my most recent test I'm seeing the same thing. Focusing creeping up from 2mm up to the 14mm range when stopped down on both my 1D2N and 1D. On the 1D2N it starts to creep from f/2 stopped down. On the 1D it starts from f/1.2. I have a lot more natural light to work with today than I did last night just using tungsten light. My test may be flawed, so I'm going to get a second opinion on it. Gary?
Edited by lord_malone on Jan 21, 2007 at 12:21 PM GMT
I will add that my real world shots are still yielding excellent results on both bodies, which leads me to believe that my tests may not be an accurate reflection of real world performance. Nevertheless, I'm getting a second opinion. You guys got me all paranoid and shit.
lord_malone, we did not mean to make you paranoid! If it works for you then use it and enjoy it! My problem was that I could not get consistent results in real life....if I could have, I would not have started this testing crap!
Yeah I got a bit paranoid also after reading this thread. Other than that rush job in December that I did with the 50L I didn't have much time to play around with it until today when I took it out for a stroll in the first snowstorm of the year here.
It is one of the sharpest lens I've used. Would even say on par with the 200/1.8L. My non-scientific testing is that the images do not need to be sharpened in post processing. When I don't goof up with the AF of course.
wcastleman wrote:
I have been following the discussion on backfocusing with interest and puzzelment. After testing two 1.2L's from the UU1000 batch, I have encountered no backfocusing issues. In my resolution tests, I was using a 51 inch working distance, focused at f/1.2 and fired at various f/stops.
if you're feeling lucky, try focusing closer to minimum focus distance and see what happens. using AF, mine backfocuses as i stop down. the only way to compensate is to throw it in MF, use the DOF preview, refocus using my eye instead of trusting the focus confirmation light, and taking the shot. then, and only then, will i finally have the shot in perfect focus as intended.
at or close to infinity focus, none of these issues show up on either copy i've had. the problem is at close focus and large apertures -- and that's where i plan to use this lens at least 50% of the time. if i only used it at 6+ feet subject distance or as a landscape lens, i'd have no complaints.
i'll stand by this lens mechanically. it's something in the focus system electronics that needs help.
Those shots are very good, Anna! Which confirms my belief that this lens is optically just as good as any in the Holy Trinity. Looks like you've got a winner to me.
). 
and buy a 50 f1.2 and see 
