A problem with speed shooting....

JamesMartin · Aug 28, 2005

Hey all,
I am new here... and new to digital cameras.

I have got myself a Canon EOS 20D with a 17-85mm lens. When I am shooting moving shots (sports mainly) on any size setting (auto everything else) it seems that the camera is not focusing on the target properly, and it is not just because the target is moving closer to me, sometimes the target is moving 'with' me.

As I have said, I am new to this whole game, so if anyone could offer advice, that would be great.

Thank you
- James

hobbes28 · Aug 28, 2005

Welcome to the forums, James.

It sounds to me like you need to change the focus to Servo mode. That way the camera knows to focus on the closest subject and can predict where it's going to be when you squeeze the shutter. I'm not sure where that change can be made but I'm sure you can find it in your manual.

Hope this helps.

JamesMartin · Aug 28, 2005

Hobbes28,

Thanx for you idea.. I will give that a go tomorrow when I am running around

I will read up the manual and see what I can find out about 'Servo' mode.

Thanx again.

- James

ksmattfish · Aug 28, 2005

Google "20D" and "autofocus" and you find hundreds of people commenting on the lack-luster AF ability of the 20D. I've been using one for about 6 months now, and 1 out of 3 times it can't accurately (at least to my standards) focus on a subject that is perfectly still.

usayit · Aug 28, 2005

As mentioned... .servo AF mode. Have you tried shooting with the aperature stopped down a bit more?

JamesMartin · Aug 28, 2005

ksmattfish,

Good to know that someone else is having problems with the same thing.

usayit,

I will try stopped the aperature down and see what happens, although that will slow the camera down? From what I think I know, which I know is limited

The aperature lets in the light, faster the rate, the less light (so the darker the image) and other way around for slower.??

Am I on the right path? or wondering in the bush somewhere???

Smith2688 · Aug 28, 2005

Yes, but stopping down the lens also allows more of the frame to be in focus so your focus point doesn't have to be *dead on*.

If it's bright enough out you shouldn't have much of a problem stopping down.

The picture shouldn't be darker unless you keep the same shutter speed. If you make the shutter speed one stop slower for every stop that you slow down the lens, you should be fine (provided the shutter is fast enough to stop the action).

Sorry for being wordy. :X

JamesMartin · Aug 28, 2005

Smith2688,

Phew, glad to hear that something I said makes sense

Most of the time there is enough light, although I live in a town where there are all 4 seasons in one day.. so it is hard to catch up

I will have a play and see what I can do, I have a tripod, so I might test out some shots with different settings and see how things turn out.

PS:... some great photos in the gallery

Thanx again.
- James

Smith2688 · Aug 28, 2005

hahaha...no problem. Definitely be sure to check out the Servo Focusing though, it should help.

Oh thanks...it's kinda stark, but I'm working on adding things. There a few random pictures in there that I need to move to different albums (called something like Camera Tests or something).

usayit · Aug 29, 2005

Yup.. Smith elaborated on what I was trying to say. Stopping down the lens ( smaller aperature opening ) will increase depth of field. Since more depth of the scene will be sharp, there is more room for focusing error.

If you want the greatest depth of field, you set a small aperature and focus at hyperfocal distance. Its a technique many journalists use to get the maximum depth of field and allows them to snap away with less worry about focus. Everything from hyperfocus distance to infiniti will be sharp. Ever notice journalists holding cameras above there heads snapping pictures?