20D Focusing woes

Hi all, I'm a pro using a Canon 20D and really like the camera but I'm having some focusing issues.

It seems the camera's focus is falling somewhere short of the subject and it's causing us major headaches here at the magazine.

The camera has been back to Canon Pro Services twice where they claim that nothing is wrong with it yet, I keep returning from the road with soft images.

I am photographing motorcycles with the zoom (70 -200 2.8L IS USM) racked out to 200mm and usually at f5.6 for minimal depth of field. I have the camera mounted on a good tripod, the stabilizer switch "off" and I'm using a shutter release cable even though I'm often shooting at 1/1000 sec and still the images are soft. Sometimes the camera focus will fall short by 6 to 8 feet. Other times it over shoots.

I have used it with all the focusing sensors activated as well as just using a single one. I'm at a loss as to what my next step is.

Does anyone have a similar problem? How did you solve it?

take some sample shots with the problem, and overlay an image of where the AF points are. See if any of the AF points are in focus. I had that problem with my old 20D -- even with only the center AF activated, in AI-servo, the camera would focus on the wrong spot, under one of the other AF points.

good luck

Hi Tele-Bob, welcome to POTN.

Are you using AI Servo, One Shot, AI Focus? Why are you using a shutter release cable? That sounds really odd. Are you not panning and looking thru the VF? What percentage of shots are soft? Sorry for all the questions, but this data will help.

Sounds to me like the AF mode you are using is falling short. AI servo on the 20D is Ok, but nothing like the 1 series. My copy of the 70-200 2.8 IS was some what soft racked fully out to 200mm. But at 198 it was razor.

Hello,

I don't have any experience shooting motercycles. Are the bikes moving? If so, are they coming towards you or are they traveling across the frame? I've seen some amazing bike shots taken by folks who have mastered the art of panning the camera with the bikes as they speed by. Generally in this case, they don't use a very fast shutter speed. Something around 1/200s or so seems to work well.

Here's a (very fast) car that I photographed with a Digital Rebel/300D at 1/250s:

I'm having focusing issues with the bike sitting there dead still!

I am using a tripod, shooting with the "one shot" setting, AF. The image appears to be sharp in the viewfinder but is not when I look at it on the computer.

Now here's the strange part. It's only when shooting the side of a bike that this occurs. The shots where the bike is angled are almost always perfectly sharp.

I will try backing off the zoom to 195mm and see if that helps. This has become a very serious problem.

Post some images. That might help to see what's going on....

I suspect that the autofocus system is finding a contrasty edge in the subject (lined up with one or more of the focus points) that is not the motorcycle.

Try switching to using a single focus point (I use ONLY the center focus point) and make sure that that focus point has a nice contrasty edge to work with on the motorcycle.

single focus point for non moving objects
I use all focus points when shooting bikes moving when the track is clear.
It would really help if you posted some pictures.
See there is nothing else in the area so all focus points are used because they are fast buggers.
(I missed the nose of pedrosas bike there)

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Post some images. Without any, it's a case of the blind leading the blind.

Thanks guys. I was thinking there might be an inherent problem with this camera model and that perhaps people would step forward and say "the problem is XYZ"

There is no problem in my method of shooting. I've been a pro for 15 years and have never had these issues with any other camera. In fact, the boss here has the identical camera and I'm not having any problems when I use his. I also read somewhere that someone tested 6 identical 20D's and 3 of them had AF issues.

I'm going to send it back to Canon, (for the third time), and ask that they shoot some actual images to examine. I'm baffled.

Thank you very much to everyone who chimed in here.

Nice MotoGP shot! I'm a HUGE fan btw and used to shoot lots of AMA stuff here in the states. Broke my heart when Rossi tossed it away after such a huge comeback this year. He's still "the man" though!

Check this link out:

https://photography-on-the.net/forum/showthre​ad.php?t=242816

I note you have not posted any photos to enable others to suggest avenues for you to explore, so I have found the above link which may be of help to you.

Remember, without evidence of your problem, you might aswell talk your problem through to a blank wall! A lot of people may have similar problems to you, but, evidence and facts together could result in a solution or diagnosis for you to consider.

Regards

Mark