10 D Auto Focus problems

[ronchast]

Anybody have auto focus problems with the 10D ?
I have set it up in the studio and locked focus on sthe subject and randomly it will be out of focus. I did family portraits the other day and about 1/3 of the shots are out of focus and I was VERY careful to lock on and get the "beep". I have tried all three focus modes but the problem seems to be random. Bad deal when I do weddings, so I take my D 60 along and shoot with both now. Any help ?

[defordphoto]

You're probably having focus-point issues. The 10D does not have a focus issue anymore. Those days are long past. Make sure you're using the proper focus-point and maybe set the center only as your focus point until you become more accustomed to the camera.

[ilya]

You may want to search this forum for a guy named Mishkin. That guy's devoted his entire life to figuring out why HIS 10D doesn't focus right. You will run the risk of losing your mind though (or going blind). Alternatively, if you're convinced there is a focus problem, take it in to a Canon service center. I've seen a few folks come back revitalized and full of life after having been to the brink of AF suicide.

Ilya

[Belmondo]

ilya wrote:
You may want to search this forum for a guy named Mishkin. That guy's devoted his entire life to figuring out why HIS 10D doesn't focus right. You will run the risk of losing your mind though (or going blind). Alternatively, if you're convinced there is a focus problem, take it in to a Canon service center. I've seen a few folks come back revitalized and full of life after having been to the brink of AF suicide.

Ilya

Come to think of it, we haven't heard from Mishkin in quite a while. What do you supose he's up to? Just when my headaches were starting to clear up, you invoke his name. Nothing good can come from it.

[PaulB]

Mishkin seems to haunt the forums - not just this one - under a variety of nom de plumes, and has been banned from at least one of them!
I know what you mean by headaches clearing up though and now he gets recommended to a poor unsuspecting newbie - only on second post - have mercy please.

I don't doubt that Mishkin/whoever he was/is now did have some problems with his AF but his search for dubious formula to explain it rather bordered on the obsessive and near hysterical.

If you are reading this Mishkin then none of us harbour any grudges and wish you well - hope the AF problem got sorted.

[ilya]

I did caveat appropriately (lose mind/go blind) upon invokation...

[ronchast]

Thanks all, I will avoid the Mishkin ??

I have locked on to all the focus points - if the camera is not known for the problem, then it is probably something I am doing wrong - just wish I knew what it was ...

Ron

[CyberDyneSystems]

belmondo wrote:
ilya wrote:
You may want to search this forum for a guy named Mishkin. That guy's devoted his entire life to figuring out why HIS 10D doesn't focus right. You will run the risk of losing your mind though (or going blind). Alternatively, if you're convinced there is a focus problem, take it in to a Canon service center. I've seen a few folks come back revitalized and full of life after having been to the brink of AF suicide.

Ilya

Come to think of it, we haven't heard from Mishkin in quite a while. What do you supose he's up to? Just when my headaches were starting to clear up, you invoke his name. Nothing good can come from it.

What is he up to?

Photographing more rulers,.. you know the engineering tyope with 10s of thousands of an inch :D

[stevelew]

I had the same problem with my first 10D. My friends told me to use the single focus point for focusing but it didn't matter. The camera would zone back and forth without locking on to the subject. It would work about 1/3 of the time and other times it would hunt. I sent the camera back to Canon about 5 times and they couldn't duplicate the symptoms. After trading camera's with another photographer who lives in Irvine, I believe that Canon finally fixed it because that photographer also had the same problem. It's not the lens because it did the same thing with all lenses. It is an internal problem with that camera. Canon should be able to fix it for you. Good luck!

[MichelM]

Recently I had what I believe to be a similar problem. During a small christmas get together, I noticed that upon many attemps at focusing, the camera or what I saw through the camera was not clear at all. Other people tested it, and they came to the same conclusion. I waited one day, to make sure the alcool was not the problem, and I came to the same conclusion that what I was seeing was far from clear. I tested it by using the same lenses on my old CANON EOS 650 and quite a difference. I took the camera back to the store and they did tell me that they had similar problems. I took the camera back to Canon, and I am waiting.

I will let you know what happens

[vvizard]

Disclaimer: I don't doubt that anyone of you have had "real" focus-issues. I will just like to state something, so that newbies (like myself) reading theese posts don't get paranoid about their cam having focus-issues.

10D uses a passive focus-mechanism, rather than an active. What that means, is that no light or high-frequent sound is emitted from the camera when it tries to figure out distances to the subject. It simply relies on "looking" at the subject, and monitoring selected pixel-values on the CMOS-sensor. It then drives the (in case of mdern Canon) USM-motor in/out while constantly reading off the before-mentioned pixel-values. When the contrast between the pixels beeing monitored is highest, the camera stops the motor, and expect that focus is fine. Although, if it doesn't "sense" good contrast, it will hunt. All the way out, and then all the way in (or vice versa), and give up.

So do you have to have a bad camera for this hunting to happen? No way, all you have to do is point it at something with low contrast. Like straigt up in a blue sky without clouds. Of course you don't do that much (I hope), but from my short experience, there's a lot of (everyday) things with contrast low enough for hunting to occour. A one-coloured sweater or similiar might actually be enough. And in low light (or slow lenses) things get worse. Honestly.. This is life, and we have to deal with it.

Of course, this is based on what I've come to think so far. And if somebody else know for sure that the cam use an active focus-mecanism, then I'm _very_ wrong here, and will send my cam to Canon tomorrow, cause then I have focus-issues =)

And just to state the disclaimer again: I don't doubt any of you guys are actually having real focus-issues, I'm just trying to prevent a lot of newbies from clogging up the Canon service-centres with "fake" problems. If I'm lucky, maybe this means one less in front of me in the queue, when I experience some issues myself =) For example if someone now tells me that the cam indeed uses active focusing =)

Happy shooting! And to the newbies, never ever shoot rulers! If you got focus-issues which you need a millimeter-ruler to verify, then you got no issue after all ;) Except maybe if you shoot extreme macro-stuff. Anyway, happy shooting, and I would just like to wish you all a very happy "BIG WHITE" Christmas =)

[vvizard]

Just to shoot myself a little..

How the heck can passive-mode focusing work at all? How can the cam figure out the contrast of a scene separated by both a shutter _AND_ a mirror? You know what? I've _REALLY_ managed to confuse myself this time! Please enlighten me, I can't sleep unless I figure this one out :/

[vvizard]

Oh thank God. I managed to find out before comitting AF-suicide myself =)

http://www.canondslr.com/articles/af-how/

And.. hehe, look at the bottom of that page:

© 2003 Mishkin

Is this the same guy you where telling about that was close to comitting AF-suicide himself? =)

[ronchast]

Thanks everyone !!! It may very well be the contrast thing thats getting me messed up. It does beep and lock on but when I open it on the PC, they are fuzzy.

Merry Christmas all


Who is this Mishkin ?? did he do that AF article at that link above ?

[vvizard]

If it beeps, then things "should" be in focus. The 10D is babysitting us a lot in this field. It won't fire unless it thinks it got good focus. Maybe that can be turned off by a CFn-X, but I'm to tired to look now.

But what lens/aperture are you using? I also get the occasional off-focus shots, probably 1/3 (or maybe more), but there's no way I'm gonna blaim that on the camera. They're not like WAY out of focus, but a little bit. Usually caused by me shooting wide open, or trying to handhold 200mm on just a bit to slow shutter-speeds.

But I'm not concerned about the camera beeing faulty. I'm in heaven! I've come from the P&S world where the cameras have a random-number-generator to generate the focus-distance. At least they act like they had one =)

[ilya]

ronchast wrote:
Thanks everyone !!! It may very well be the contrast thing thats getting me messed up. It does beep and lock on but when I open it on the PC, they are fuzzy.

Merry Christmas all


Who is this Mishkin ?? did he do that AF article at that link above ?



Mishkin is actually a very smart guy, and you can learn some stuff on his website about auto focus, if you have a big grain of salt. He is however overly obsessed with trying to prove (I think) that the 10D has an AF design flaw. Or at least that's how his theorems start out. He gets there using a mix of science and pseudo-science, which causes lots of outrage on various forums from the vast majority of 10D owners whose cameras AF just fine.

So to vastly oversimplify something I am not educated enough to understand fully, its like saying that because your new Ford Explorer had blown a gasket, that means Ford should recall all Ford Explorers because the way they built the Explorer engine allows a tiny, small percentage of gaskets to be blown.

From what I observed, there are a few camera bodies that have an AF problem. That problem is apparently easily fixable by Canon service. My camera, and the vast majority of other 10Ds focus just fine. The best way to avoid an AF problem is to try out the body before buying. Whether you have a shop around the corner that will help you with that, is another thread and apparently another controversy!