If you own a 1Ds3 and a 35L, would you find the following AF performance acceptable if you compare it to MF performance?
This was shot in sequence (f/1.4 AF/MF, f/2 AF/MF, f/4 AF/MF) using the most upper right AF point. Camera was on tripod, slowest shutterspeed was 1/125:
As you can see, by f/4 the differences between AF and MF are virtually gone. But I didn't bought this lens to use it at f/4 and smaller. Would these differences between AF and MF fall within specs?
Not to me they wouldn't. Even at f/4 you can see the difference--that's bad. I don't know about in Holland, but in the U.S. I've been successful in getting a lens properly calibrated by Canon by sending them comparison shots of AF vs. MF. Then again, they probably just calibrated it without looking at the sample pics I sent, so who knows. Your situation is more complicated though, isn't it? Doesn't it AF just fine with the center point but not with the outer points? Sounds like a body problem instead a lens problem if so.
Shivatron wrote:
That's certainly unacceptable for a pro-level body and a $1k+ lens. Send it in.
Glad you feel the same way. Unfortunately this combo was already serviced twice. Before servicing it was way off when using the center and outer AF points. AF performance has improved after servicing, but there is much left to be desired.
thedigitalbean wrote:
Have you tried using the AF micro adjustment?
No, and I won't go there either. I get very mixed results with all AF points. They all seem to behave differently. MA will only shift the problem. I think MA is a too simple tool for such a complex situation as this.
Daan B wrote:
Glad you feel the same way. Unfortunately this combo was already serviced twice. Before servicing it was way off when using the center and outer AF points. AF performance has improved after servicing, but there is much left to be desired.
Really? That's nutty. Canon really needs to get its act together with the new AF system. It strikes me that the old AF system (which took us from the EOS-3 right through the Mark II) never had the widespread problems that the Mark III AF system seems to face. I wonder why?
Shivatron wrote:
Really? That's nutty. Canon really needs to get its act together with the new AF system. It strikes me that the old AF system (which took us from the EOS-3 right through the Mark II) never had the widespread problems that the Mark III AF system seems to face. I wonder why?
You know what's nutty..? The AF on outer AF points seems to degrade when I move into wide angle territory. My 24-70L focuses consistently using AF and MF @ 70mm. But when I use the 24-70L @ 35mm on the outer AF points, I get similair results as with my 35L: visible differences between AF and MF (where MF has the better performance). The longer I get, the less AF problems I seem to have on the outer (and center) AF points.
I just sold my 35 f1.4 because of this. I have gone back to my trusted manual focus methods: Zeiss 35 f1.4, concentrate hard, bracket heavily, and use liveview whenever possible. Canon's current AF system is not accurate enough, after calibration, for reliable placement of focal plane with wide aperture lenses (24, 35, 50, 85, 135). Get the Ec-S and go manual - it works.
brainiac wrote:
I just sold my 35 f1.4 because of this. I have gone back to my trusted manual focus methods: Zeiss 35 f1.4, concentrate hard, bracket heavily, and use liveview whenever possible. Canon's current AF system is not accurate enough, after calibration, for reliable placement of focal plane with wide aperture lenses (24, 35, 50, 85, 135). Get the Ec-S and go manual - it works.
Brainiac, I have to say that after reading your posts and seeing the images on the Alt. board, I've given some thought to picking up a CZ 35/1.4 myself. Shame that they are almost as expensive as the EF version of the same lens (which could theoretically be used in MF)...
I had AF issues with a 35L on a 5D before. I sent it in for calibration and to me, the problem did not seemed to have been fixed. I sent it in once more and was told that the head of the service center took a look at my lens and replaced some odd part and afterwards the lens worked perfectly.
You should express your concern in letter or in person (if possible) and ask them to be more thorough during the inspection process. Though its bad form to miss such an issue after 2 rounds, I'd give it one more shot and see if they can fix it!
BTW, I dropped my lens (without body) off directly to the Canon Irvine service center.
Best of luck!
Jason
Edited by Jason Joo on Jul 03, 2008 at 11:14 AM GMT
I wonder, have you tried to replicate this test with say a 300/2.8 IS?
My Canon 'loaner' 1Ds3 arrives tomorrow and from all I have read on FM, the problems are primarily with the 35L which few seem to be happy with, but I don't remember reading any problems with long lenses.
BTW There are others with the same issue... I wouldn't be surprised if all 1D(s)3 cams show the same issue.
A lot of people blame the resolving power of the 21MP sensor or a strong AA filter for the lack of sharpness in 1Ds3 files... I wonder if these people ever tried MF with the 1Ds3?
Alistair Watson wrote:
I wonder, have you tried to replicate this test with say a 300/2.8 IS?
My Canon 'loaner' 1Ds3 arrives tomorrow and from all I have read on FM, the problems are primarily with the 35L which few seem to be happy with, but I don't remember reading any problems with long lenses.
Unfortunately I don't have a 300/2.8IS. But like I said, the problems seems worse with WA lenses and with wide(r) apertures at (medium) tele FL's. My 85L II is only good by f/4 and smaller (meaning no difference between AF and MF). From wide open to f/2.8 MF gives better results on the outer AF points. The further away from the center, the worse AF becomes.
Alistair Watson wrote:
My Canon 'loaner' 1Ds3 arrives tomorrow and from all I have read on FM, the problems are primarily with the 35L which few seem to be happy with, but I don't remember reading any problems with long lenses.
My 35L works flawlessly but no amount of prayer etc. will make my 24L work reliably. Granted, even less magnification, but still annoying.
