10D Focus Problems / Focusing Point Problems / HEEEEEELP!

[GonzoMan]

Hey gang, I know that the 10D focus problem "thing" has been run into the ground, but I have yet to find any answers to what exactly the problem is.

I just bought a "Like New" 10D body off of ebay and a brand new Canon 24-70 f2.8L USM lens from B&H Photo in NY. I took that setup out today and shot about 100 pics - half of them came back "waaaay" out of focus. As I shot today, I changed the focusing point a lot - trying to get used to using this feature.

Realizing that there may be a relation to my out of focus shots and the fact that I changed focusing points thruout the day - I did a little test this evening. I shot pics of this water bottle "utilizing each focusing point". The sharpest pics came while using the center focusing point and the worst (most out of focus) pics came while using the focusing point on the right side of the center one.

This pic shows a comparison between the center focusing point and the next one over to the right. The center focusing spot makes the sharpest pics and all the other ones and not as good.

http://www.imdino.com/focus_test.jpg

I was wondering if any of you guys have ever done a test similiar to this and if this may be the cause of some of the bad focusing problems that we're experiencing?

I also wondered if this is a repairable problem?

I have been a Nikon shooter for 15 years and just recently sold all of my Nikon gear (3 bodies and 7 lenses) to start investing in Canon gear. I am so dissappointed right now in Canon - I'm not sure I want to continue buying their gear. I have read a lot about this focus problem on the 10D's but can't find anything where Canon acknowledges that there is a problem and how to go about getting the camera serviced -

Thanks,

Dean*

[robertwgross]

It sounds like somebody on eBay successfully dumped their used Canon body on you.

So, you are disappointed about all Canon gear now?

If somebody had purchased the body originally and then sold it very soon, then that suggests that they found something that was either broken or they didn't understand.

Why don't you approach this systematically? Send the camera and the lens into Canon repair and tell them as clearly as possible what you think you have in focus problems. If it is a back-focus or front-focus problem in the camera, then they can find it and adjust it out. Or, if it is a lens problem, they can find it. It's unlikely that a brand new lens would have a problem like this, but anything can happen.

You haven't done the ruler test, have you?

---Bob Gross---

[KennyG]

Before you do anything else, re-set the camera by removing the main and button batteries to make sure you have cleared all settings. You will have to re-enter the date etc, but you will start from a known baseline.

Use a target that is flat, no reflections and that has a lot of contrast for the focus point to work on. Shoot in Av at maximum aperture, making sure you have a lot of light. Do NOT use flash.

The centre focus point is the only one that is in the form of a cross and it could be grabbing a better contrast area than the adjacent points which are horizontal. The red squares are only a guide, not the exact boundaries of the focus points.

If the results are the same then you may have a problem. I have tried a quick test following your post and, using my 85 1.8 lens wide open, all points focus perfectly. I personally doubt that there is a fault with your camera.

[GonzoMan]

Thanks Kenny - I'll try that and see if it helps.

I'll keep ya' posted!

:wink:

[GonzoMan]

Nope - still having the same problems - even worse at f2.8.

I did test the manual focus and all is well. I got crystal clear images manually focusing at f2.8. It's the auto focus that screwed up.

Looks like I'll be visiting the Canon repair shop up in LA this weel :cry:

[GonzoMan]

It sounds like somebody on eBay successfully dumped their used Canon body on you.

So, you are disappointed about all Canon gear now?

If somebody had purchased the body originally and then sold it very soon, then that suggests that they found something that was either broken or they didn't understand.

Why don't you approach this systematically? Send the camera and the lens into Canon repair and tell them as clearly as possible what you think you have in focus problems. If it is a back-focus or front-focus problem in the camera, then they can find it and adjust it out. Or, if it is a lens problem, they can find it. It's unlikely that a brand new lens would have a problem like this, but anything can happen.

You haven't done the ruler test, have you?

---Bob Gross---

Bob - thanks for your comments. I am only dissappointed in the fact that I see people discussing their focusing problems with the 10D all over the internet. They are talking about them on baords like this, on their websites and even reviewers are discussing it. I have yet however found anything in regards to these focusing issues on the Canon website.

A company who doesn't stand behind their product enough to tell the public about issues like this and to acknowledge that there is (or was) a problem - well, it makes me wonder if this is the kind of company that I want to invest more money in...

Dean*

[KennyG]

Well, that is the first time I have seen that particular problem. To correct my above post, the adjacent (right and left) focus points are vertical, not horizontal.

The centre point is the more accurate, but that still does not account for the huge difference between points.

As I said, take shots of a flat high contrast target at each of the points and take copies of your results with you. Do it at 2.8 which is the worst case scenario.

I am sure they will sort it out for you. Not all 10D's have focus problems, mine certainly doesn't and neither do those belonging to people I know personally. It is an issue that has been blown out of all proportion by a very few people across various groups. Once sorted you have a great camera.

[garethhhhh]

10D's do have problems focusing in low light, but nothing as bad as that in broad daylight.
I have a 10D & I've never had results even close to that. The 10D is a very good camera, either you have a bad copy or the person you bought it from damaged it in some way & tried to offload as fast as he could.

Take it to te service center right away. :wink:

[iwatkins]

Could it be that the AF sensors has just got some dirt on it? Maybe worth a clean.

Cheers

Ian

[Jim_T]

Your focus problem is unique..

The biggest focus complaint with the 10D was that some of the cameras sold consistantly front or rear focused, but it never mattered what focus square was used.

While it was a real problem, (Canon Germany acknowledged it), I don't know about how widespread it was. It seems a dedicated group took over most forums complaining endlessly about focus problems under different names.. If you look around now, you'll see the problem is no longer as 'bad' :)

I agree with iwatkins, The fact that only ONE focus point is acting up means there may be dirt over the focus sensor, or it's gone out of alignment or has gone bad. Do any other focus points display this trait ??

Finally.. I only use the center focus point. This prevents the camera from focusing on the wrong part of the frame.. (This has been an issue with the 7 point focus). Losing another square wouldn't be the end of the world for me :)

[GonzoMan]

Do any other focus points display this trait ??


Yes. The center focusing point produces the sharpest pictures, although not consistantly sharp. The focusing point just to the right of the center one produces the worst pictures. The other focusing points are somewhere in between.

I am communicating with Canon now via email about the problem. Will keep you guys posted. Thanks a bunch for your thoughts and advice.

Here's a little something that I shot with my Nikon setup a few months ago. Hope you like.....

Dean*

[NUDITY] http://www.deancapture.com/images/pantera_red.jpg

*If this picture is not appropriate for this forum, please let me know and I will remove it.

[robertwgross]

A company who doesn't stand behind their product enough to tell the public about issues like this and to acknowledge that there is (or was) a problem - well, it makes me wonder if this is the kind of company that I want to invest more money in...


If you had been the original purchaser of a new camera from Canon, then that would be one thing, but when you purchase somebody else's junk off eBay, you don't know what you are getting. (Right, Belmondo?)

In the early days of the 10D body, there were some front- or back- focus issues, but those became well understood and then corrected. Did you do the ruler test on yours to see if that is relevant?

---Bob Gross---

[Sendide]

Hi everybody
this focusing pb issue is coming out so often. I have got a second hand 10D too, looks perfect so far, but since the guy sold it soon after buying it (saying that he wants a full frame camera or closer (1D)), I'm liitle woried. I do mostly macro photography and as you know its always manual focusing. couple shots I did with 100mm macro and 28-105 USM were prety sharp but always with the flash help (550EX). I think I have to do this "ruler test" but have NO IDEA about it.
any help please?
thanks in advance.

[Wickedfn4u]

What is the ruler test? I would like to try it and see if mine is working correctly.

TC

[robertwgross]

I can't find the instructions here right now. Let me describe it.

Take a long ruler or a yardstick and set it reclining at about a 30 degree angle. Step back from the low side about five feet. More if you are using a long lens. Use only the center focus point. Focus on some inch mark of the ruler, e.g. 5, and make note of that number. Shoot it.

Take the image into your computer and study it. If your camera has proper focus, you will see that mark 5 is in perfect focus, and everything from 4.5 to 6 (depending on DOF, of course). With a tight DOF, it might be only 4.9 to 5.1. That is normal.

If you study the image and see that everything is in focus from 4.1 to 4.9, then that is a front focus problem. By the same token, if everything were in focus from 5.1 to 6.2, then that is a back focus problem. These are just example numbers.

---Bob Gross---

[slin100]

The ruler should not be the target of the test because it has too many high-contrast lines, any of which the camera can lock onto. The ruler should be off to the side of the image. The target should be a single high-contrast subject on a plain white background.