Canon eos 10d auto focus - DPChallenge Forums

Sigma 105mm f/2.8 EX DG Macro for Canon

06/06/2004 07:39:42 AM · #1

I got my Canon yesterday but my lense didn't come down with it. I found a friend with 2 canon lenses (for his 35mm cam) - EF 28-80mm 1:3.5-5.6 II and EF 80-200mm 1: 4.5-5.6 II.

My photos are coming out slightly blurred, not much but enough. The AF locks and it looks great through the view finder. Have tried with high shutter speeds on a tripod, with the timer and still get the same problem. Is there anything i can do or will my Sigma 70-300mm 4.5-5.6 macro super II not have this problem when it arrives?

Tranquil

Canon EOS-300D Rebel

06/06/2004 07:41:35 AM · #2

Try to take a few shots on a tripod. This might be a case of slight camera shake. If you want to post some examples, that can help us further se what the problem is.

Lee

Canon EF 28-135mm F/3.5-5.6 IS USM

06/06/2004 07:43:55 AM · #3

Can i post examples if i am not a full member yet? I don't think it is camera shake, i have tried on tripod with 1/1000 shutter speed with the timer and no wind!

ClubJuggle

Canon EOS-400D Rebel XTi

06/06/2004 07:49:03 AM · #4

You can post examples if you have another place you can upload them. Just upload them there and create a LINK to the images in the forum. Please do not embed the images themselves, as they will likely be large and load slowly for dialup users.

-Terry

Tranquil

Canon EOS-300D Rebel

Sigma 105mm f/2.8 EX DG Macro for Canon

06/06/2004 07:50:48 AM · #5

Bio, as for your latter statement, I am not sure what the problem is. It may be the glass and it might even be your vision although that does not make much sense since it is AF. Is is possible htat these lenses cannot comply to the Passive AF used by the 10D as opposed to the possible Active AF originally meant for the lenses?

06/06/2004 08:03:02 AM · #6

I'll try to upload an example now.

My vision is ok and like you say, it does lock the af. I'll get the example there in a few minutes, its not way out of focus but not sharp.

Thanks for helping.

Canon EF 135mm f/2.0L USM

06/06/2004 08:40:22 AM · #7

Focus problems

Here are a couple.

JC_Homola

Canon EOS-20D

06/06/2004 08:49:05 AM · #8

I have a feeling it's the glass,,, I had my first shot's look like that, before I got my 50mm prime. The 2nd one also looks like it has a little shake in it....

Tranquil

Canon EOS-300D Rebel

Sigma 105mm f/2.8 EX DG Macro for Canon

06/06/2004 08:50:26 AM · #9

Ok here's my take.

On the first one, your metering and focusing system took the wrong part of the image as the subject. If you were trying to focus on the flower, it focused on the tree because the tree was what it found to be the subject of the composition. The flower might have been a major distraction to the system so although it thought the tree was in focus, it also may have thought the flower was and it averaged them out so your focus seems to be somewhere in the middle, although a little bit towards the tree side.

For the second, the focusing system may have just focused too shallow or too deep. For specific shots without fast moving subjects and when you can take your time, you should take the time to manually focus if your AF is an issue. It probably shouldn't be like that, but it does happen.

Manually focusing in my shots generally gives a better, less flat result than when I AF it. There are certain things that should almost always be done with AF, like sports. There are other things that require manual focus like still lives. The camera does not know (although some come close) your photographic intentions. Remember, there are just algorithmic computations and equations going on in there :)!

It may be necessary to hold the shutter down half way more than once, so that camera takes different reading until it gets it just how you like it.

Hope this helps,
Lee
Edit: The glass could play a role as well :)

Message edited by author 2004-06-06 08:52:05.

ClubJuggle

Canon EOS-400D Rebel XTi

Canon EF 28-135mm F/3.5-5.6 IS USM

06/06/2004 09:31:34 AM · #10

Sam,

When your camera locks focus, be sure to pay attention to what it locked on... which will be indicated by one or more of the guide squares briefly flashing red in your viewfinder.

In your first shot, the image is perfectly focused on the tree in the background. This is not surprising as it runs across the center of your image, and four of the seven focus points (indicated by the above-mentioned guide squares) on the camera would have been trained on it. The flower that I assume you intended to focus on is in the corner and therefore not in the path of any of the 7 focus points. You can work around this by training the camera on the flower, pressing the shutter halfway to lock focus, and then moving the camera to frame the shot as you like before pressing the shutter the rest of the way.

Though it is hard to tell at this size, I believe the problem on the second shot is the same. The planter in the background on the right side seems to be in focus. There may be a slight bit of camera shake here as well.

I don't think it's your glass.

-Terry

Hakon

Canon EOS-5D

Canon EF 24-70mm f/2.8L USM

06/06/2004 09:48:32 AM · #11

I have a Canon EOS-10D and I have similar problems with my camera.
I have Canon EOS 24-70mm lens 1:2.8
It is usually ok if I take photos between 24 and 40 mm but if I use it between 40 and 70 mm I many times get the photos slightly blurred.
It doesn't matter if I use shutter speed at 1/1000.

-Hakon

scalvert

Canon EOS-5D Mark III

Canon EF 24-105mm f/4.0L IS

06/06/2004 09:54:49 AM · #12

If your intention was to get everything in focus, use a higher f-stop to get more depth of field. Oh, and don't enter these in the Deep DOF Challenge- you'll get spanked. ;-)

Nusbaum

Fujifilm X-T1

Canon EF 50mm f/1.4 USM

06/06/2004 10:01:56 AM · #13

I set the auto-focus on my 10D to only use the center focus point so I can reasonable sure it focused on the right part of my composition. The auto-focus sensors are big and it still misses occasionaly.

Canon EF 24-105mm f/4.0L IS

06/06/2004 11:17:04 AM · #14

Thanks for your comments guys, very helpfull. I should have mentioned but the first shot was supposed to have locked on the tree with the center 3 af points and the second was locked on the cigarette packet (bad habit i know!:)) I have been trying to re focus by pushing the shutter halfway and it certainly is in focus through the eye piece (which makes me think it is the glass). I also get better results from the smaller of the two lenses.

Have also tried manual focusing on tripod, with timer and still same issue.

I'm thinking (and hoping) that it is the glass. If not, there must be something with the camera as i have taken into account all the variables, camera shake, wrong af point/s, focal length, etc.

Anyway, my lens should arrive tomorrow so i'll hopefully find nice crisp images!

Thanks very much for taking the time to help me everyone!

zeuszen

Canon EOS-1Ds Mark II

06/06/2004 12:25:13 PM · #15

� AF looks for contrast near the focusing points. If there is more than a single object to focus on, it will focus on the object with the most distinct contrast.

� Lock the mirror as well, just to see if there is an improvement over shots taken without it.