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Old Dec 21, 2004, 8:14 PM   #1
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20D out of focus! "Blurry" and "soft" are nice words for an expensive camera that is not focusing correctly. I've shot hundreds of pictures using the Canon 24-70mm 2.8 lens. I tried different techniques, modes, tripods etc. and my pictures are not clearly focused - it is not a sharpness issue. All the sharpening software in the world will not correct focus. This seems to be a serious complaint from numerous users who were counting on producing superior, sharp quality pictures that Canon is famous for. This is a critical quality issue with the 20Dthat was not an issue with previous models using the same lenses.

I came across this analysis in another forum.

http://forums.dpreview.com/forums/re...ssage=11053991

This is exactly the problem I am experiencing. Wide angle shots are not focused.( Depth-of-field mode has yet to impress me either.) I sure hope there is a software fix for this inaccurate focus issue - soon.
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Old Dec 21, 2004, 8:32 PM   #2
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If youreally have this problem I think you need to take your camera and the lenses having the issues to a Canon repair site. From what I have heard aboutthis issueI don't think it is firmware fixable.

So farI have not seen this problem with my lenses. Tamron 19-35 f3.5-f4, Tamron 28-75 F2.8, Canon 100-300USM f4, Canon 75-300USM f4-f5.6, Tamron 2x TC
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Old Dec 22, 2004, 11:12 AM   #3
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Could people with this "focus" issue please post some images that they consider out of focus? I am only using the 18-55mm kit lens to date, so if anybody has some images with this lens it would be appreciated. I am trying to determine if it is the camera that is in fact a bit soft, or myself being used to over sharp consumer level cameras. I will post some of mine shortly to see what people think.



thanks

Bob
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Old Dec 22, 2004, 4:54 PM   #4
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Jasper666 wrote:
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Could people with this "focus" issue please post some images that they consider out of focus? I am only using the 18-55mm kit lens to date, so if anybody has some images with this lens it would be appreciated. I am trying to determine if it is the camera that is in fact a bit soft, or myself being used to over sharp consumer level cameras. I will post some of mine shortly to see what people think.
You can usually tell if there's a focusing issue if some part of the picture is actually "in-focus", either in front or in the back of what you try to focus on...
http://www.photo.net/learn/focustest/

It's best to do this focusing test with the fastest lens that you have, since slower lenses tend to mask the problem because of their larger Depht-Of-Field (DOF). On smaller aperture lenses such as f/4-5.6 for example try to get very close to the subject to minimize their DOF (ie an f/2.8 or even an f/1.8 would expose a camera's focusing problem more easily than a slower lens) -> You can have a problem and not be aware of it because the DOF of the slower lens is hiding it :?
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Old Dec 23, 2004, 11:00 AM   #5
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Yeah, I will have to do the focus test. But you are right, if there is in fact a focus problem, some part of the photo should be in focus. So far, my images tend to be just "soft" entirely. So I don't think I have a focus issue. I have been playing more with the f-stop and post processing to sharpen and am getting much better results. I also think this 18-55mm lens probably isn't the greatest anyhow.



Bob
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Old Dec 23, 2004, 12:18 PM   #6
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I just tried the test on that site. I even added a 45 degree block (with an extra set of marking) so that I had a flat plane to focus on.

My 20D is showing a focus point of 3cm past the plane I am trying to focus on.

Obviously I might be conducting the test wrong

I'd need to spend more time making sure I'm not fooling myself.
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Old Dec 23, 2004, 2:02 PM   #7
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Jasper666 wrote:
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So far, my images tend to be just "soft" entirely. So I don't think I have a focus issue. I have been playing more with the f-stop and post processing to sharpen and am getting much better results. I also think this 18-55mm lens probably isn't the greatest anyhow.
Actually on the 20D you're not exercising the camera's high precision AF sensor unless you use a lens with f/2.8 or larger aperture... The larger DOF of the kit lens keeps you covered anyhow

The DOF for a 55mm f/5.6 @ 1m is 7cm!
http://www.dofmaster.com/dofjs.html
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Old Dec 24, 2004, 11:05 PM   #8
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Hi:

I myself have had the same problems as has been posted by many. NHL, I have the focus situation you were talking about. Some part of the image is very clear and the rest isn't. I posted about images at 100% that are very blurry and just "not right" and after calling the Canon service rep, feel I have no choice but to send back my camera and two canon lenses so those geniuses that claim they need my canon lenses to "calibrate" can try to fix my damn camera. I have been very loyal to Canon but if this doesnt work and i'm stuck with this camera that i'm not really happy with, i'll look to sell this camera or actully maybe step back to the Canon 10D because ive read that doesnt have these problems and I like my Canon 70-200 f4 lense alot. Hope you all have a merry christmas. Jcarboski
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Old Dec 26, 2004, 6:18 AM   #9
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jcarboski wrote:
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i'll look to sell this camera or actully maybe step back to the Canon 10D because ive read that doesnt have these problems and I like my Canon 70-200 f4 lense alot. Hope you all have a merry christmas. Jcarboski
This is not a very good idea...

Even if your picture was shot @ f/4, the 20D uses high-precision sensors for the AF when the lens was wide open (ie f/2.8 for your 24-70) before the shutter was released. I would check everyone recommendation and verify which AF point the camera has picked, since the hat on the subject was clearly in focus (but not the face): http://www.stevesforums.com/forums/view_topic.php?id=42476&forum_id=37

The 10D/DRebel do not have theses higher-precision sensor... If the sensor is spot on (ie the face) and the hat is in focus instead then your20D has a slight back-focus problem which need to be re-adjusted that's all. May be the EF 24-70 f/2.8 is a new lens and you're more used to the larger DOF of the slower 300D kit lens, but the DOF is nowthinner and the camera has to be spot-on especially at close distances.
Thisissue will be even more acute when you use a longer lens such as the 70-200 f/2.8 where the DOF is paper thin! (it's a good idea to have the camera checked)

FYI on faster lens: http://www.a1.nl/phomepag/markerink/af_expla.htm
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Old Dec 31, 2004, 8:41 PM   #10
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nhl:

thanks for your help. I actully sent it back to canon last week, Ill keep you up to date how things work out, but i sent the 18-55 and the 70-200 f4 l series lense back to canon so they can do there thing, wheather it's there so called calibration or what?? but they have the camera and two lenses and they did prepay the shipping so i feel there willing to do the right thing for me. John
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