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Sharkbait
08-24-2005, 09:16 PM
Any other 20d owners having problems with the AF system? I just got a new Sigma f/2.8 short zoom (their new EX series), and in low light it focuses perfectly on my 300d, but put it on the 20d and every single image is back-focused. :? :x

ksmattfish
08-24-2005, 09:32 PM
Any other 20d owners having problems with the AF system?

It's all over the web, and there are lots of theories and explanations. I haven't been happy with my 20D AF either. I only use the center AF sensor. I've been mostly shooting with a Sigma 18-50 f/2.8 and a Canon 85 f/1.8; it does seem to be a bigger problem with the Sigma lens, but it's there with the Canon lens too. When I do the ruler test (photograph a ruler at a 45 degree angle) it seems to be working fine, but in the field it doesn't seem to be very accurate. One explanation is that the actual AF sensors are much larger than the indicators in the viewfinder.

Maybe after the fall wedding season I'll send mine in to be checked out. All I know is that the AF on my Pentax ZX-5 (circa 1997?) works circles around this 20D. I installed a split screen, and now I'm back to 100% manual focus.

Sharkbait
08-24-2005, 09:39 PM
You installed a split screen in your 20d? How'd you do that? I'm probably going to send mine in after the wedding season as well. Right now I have a $500 sigma paperweight. :|

We're switching over to 1dMkIIs in our studio...I'd love to be able to up to one of those.

Sharkbait
08-24-2005, 09:42 PM
What's odd is I put the 18-55 EFS p.o.s. kit lens from my 300d and the 20d will focus in zero light. Put on the $500 Sigma digital EX series lens and it won't focus in broad daylight. :| But put the Sigma on the 300d and it works great. So for the time being it looks like the 300d is going to be my primary body at weddings! :?

JohnMF
08-24-2005, 09:44 PM
ive had this prob too with my 20d and sigma lens, im really close to buying a new lens but if its the camera i might hold fire.

How did you get the split screen too?

ksmattfish
08-24-2005, 10:42 PM
Check out

http://www.katzeyeoptics.com/

There are other screens available. Some are cheaper. If you search there are big debates on which are better. I have the Katz Eye, and it works well, but it's the only one I've ever tried. The viewfinder is still too small.

danalec99
08-24-2005, 10:51 PM
We're switching over to 1dMkIIs in our studio...I'd love to be able to up to one of those.FYI they are replacing that model with 1D Mark II N (http://www.dpreview.com/news/0508/05082208canoneos1dmkiin.asp).

Bosscat
08-29-2005, 11:33 AM
Don't go ask anything about this at the Canon forum. They'll just say that your at fault, not their beloved Canons. I am lucky to get 30-40% keepers with this camera.

Look on the bright side though folks. If this was a film camera, it would put you in the poor house.

Had my Sigma F 2.8 70-200mm EX APO HSM sent back to make sure it was compatible with a DSLR and the song remains the same.

ksmattfish
08-29-2005, 04:32 PM
Don't go ask anything about this at the Canon forum. They'll just say that your at fault, not their beloved Canons.

I don't know if it's the same Canon forum, but I was visiting one where it was generally held as truth that you couldn't be a pro without the vertical grip, and that it was impossible to photograph almost anything without AF. The forum was all about gear masturbation, and had very little about actual photographs.

Don't get me wrong, obviously my large collection of cameras demonstrates that I am quite turned on by camera gear, but I can seperate my camera fetish from where my good photos come from.

John E.
08-29-2005, 04:53 PM
I do the same as ksmattfish and only use the centre point for focusing. I mostly shoot stills, I realize weddings are a whole different ball game . I use the spot metering first and take a reading then I center the AF point on an edge that I want to focus on and quickly switch the AF to manual being careful not to move the zoom, I find I get a better success rate this way. I also like to choose the point of focus on landscapes also, I never did trust computers Glad to hear I am not the only one with AF issues . I use the sigma 18-125mm lense. What I wouldn't do for an old fashioned split screen

ksmattfish
08-29-2005, 04:58 PM
What I wouldn't do for an old fashioned split screen

See the posts above. I love my split screen in my 20D. :)

I use the custom function that makes it so the shutter release button is the meter lock, and the AF is switched to a button on the rear of the body. Not that I really ever use the AF anymore.

John E.
08-29-2005, 05:16 PM
Thank you so much ksmattfish, it is now on my must have list. :thumbup: :D

photobug
08-29-2005, 06:48 PM
If you can, try another (non-Sigma) lens before you bail on the camera. Months ago in the Pentax forum at dpreview there was a long (painfuly so!) discourse on Sigma lenses misfocussing on Pentax dslr bodies.

I believe it was a chip issue, as some of these lenses had been around quite some time before the newer bodies. It seems the short zooms were more likely to have focus problems than the longer zooms. I have a 70-200mm APO EX that will focus correctly. Newer Sigma lenses don't appear to be (as) affected.

Bosscat
08-29-2005, 07:38 PM
All I can say is that I shot over 1400 pics at a huge National MX race and ended up with 350 keepers out of it. So many just seemed to be slightly off , or way off in the focus dept.

Didn't matter what lens I used either. I am convinced that some of these cameras are poorly calibrated from the factory. I would be eaten soup for years, if I had shot that much slide film with those poor of results.

Jeff Canes
08-29-2005, 09:44 PM
Shark – I’ve heard for two photog (pro sports shooters) that they or photog that worked for them have had problems with the shutter breaking at around 30K exposures with the 1dmII. This must have be a common problem because the shutter durability is addressed on first page of new 1dmIIn specs

Have you heard anything like this in your hockey circle of photogs

Bosscat
08-30-2005, 07:26 PM
According to what I read over on a Canon forum, anyone have problems witha 20d should read this link.

http://photoworkshop.com/canon/EOS_Digital.pdf

ksmattfish
08-31-2005, 08:07 AM
I've read that, along with numerous other articles how to get the 20D to focus correctly. There are lots of good AF tips, but it doesn't really address the issue that thousands and thousands of people are posting that they are having AF issues with the 20D. I don't have these problems with my 10 year old Pentax AF 35mm SLR.

What is interesting is that some folks have both a digital Rebel and a 20D, and are not having the AF issues with the same lenses on their Rebels. I think Canon has really dropped the ball on this one, and is hoping we'll all quietly upgrade to the next DSLR rather than making them fix it (which may be impossible as many people are reporting the same problems after their camera is returned from the Canon service center).

Bosscat
08-31-2005, 11:01 AM
Guess I shoulda bought the cheaper camera and been money and pictures ahead.

Some say that after they have had theirs calibrated it works fine.

Guess its burst mode and lotsa deleteing on the laptop for this weekends sportscar race.

For this I paid 2 grand???

Digital Matt
08-31-2005, 11:05 AM
I have focussing issues with my 70-200 f/4 L. That lens has many reported issues, and I also experienced those issues with my digital Rebel and that lens, but occassionaly I will still get a back focused shot with my 85 f/1.8 on the 20D. Do those focusing screens make manual focusing "easy" with that tiny viewfinder? I have trouble manual focussing.

ksmattfish
08-31-2005, 12:11 PM
Well, the viewfinder is so small and dim that it's more difficult than with a 35mm SLR, but I'm doing better manually focusing with the split screen than the camera's AF was doing by itself. I can't wait until I can afford a full frame sensor DSLR; not because of the extra megapixels, but for the larger, brighter viewfinder.

John E.
08-31-2005, 05:45 PM
According to what I read over on a Canon forum, anyone have problems witha 20d should read this link.

http://photoworkshop.com/canon/EOS_Digital.pdf

Thanks for the link Bosscat. I downloaded and saved it. So much for Digital being simpler :lmao:

Sharkbait
09-02-2005, 07:19 PM
Well, I contacted Canon and explained my situation--that I need this body at all times because I have weddings scheduled through the end of the year. I know that Canon does a loaner program, because the studio where I shoot has used it numerous times when we've had a body go bad. But I got exactly what I expected from Canon to a small-time, couple-of-cameras customer--

Dear Mr. Wikman:

Thank you for contacting Canon product support. We value you as a Canon customer and appreciate the opportunity to assist you.

I apologize, but the only option we can offer you is to examine the camera at our Factory Service Center. Please note that we cannot address issues with non-Canon equipment, and thus we are not able to assist you with the Sigma lens. Canon EOS system cameras are designed for use with EF and EF-S series Canon lenses only. It is entirely possible that the camera would perform poorly (if at all) with a non-Canon lens attached.

Our recommendation is to have the EOS 20D and grip examined by a service technician. For factory service, please forward your digital camera to one of the Factory Service Centers shown below. When shipping your camera, please be sure to remove the memory card and batteries. You are not required to send any accessories or manuals when shipping the camera. Be sure to include your name, street address (no P.O. boxes, please), telephone number, and a letter describing the issue with the product. If it has been less than one year since the camera was purchased, we ask that you also include proof of warranty in the form of a copy of your sales receipt.



:roll:

Sharkbait
09-02-2005, 07:21 PM
Here's what I emailed back to them this afternoon:

Hi Jenny --

Thanks for getting back with me. Unfortunately, I'm still stuck between a rock and a hard place. I _need_ that camera body until at least the first of the year, as I have weddings scheduled through 17 December. Unfortunately, by that time the one-year warranty will be expired.

I understand that Canon can't be held responsible for problems with non- Canon lenses, but I am experiencing these same issues with my Canon 50mm f/1.8 and my Canon EFS 18-55mm lenses. I have done extensive testing with the Sigma lens on my Canon 300d, as well as the 1DS-MkI, 1DS-MkII, and 1D-MkII at the studio where I work, and have brought the lens in to Roberts' Camera in Indianapolis, where it performed flawlessly on another 20d. As you can hopefully see, the issue is not with the lens (Sigma or otherwise), it is with my 20d body.

If there is another solution, I would love to hear it, but the impression that I'm getting is that you've got my money, and I've got a $1500 paperweight.