Canon 20D

[Donnie]

Hi, I’m new to the forum and I have a question. I have a Canon 20D with a Canon 17/85mm lens. My pictures are sometimes tack sharp and other times they are soft. I took the camera to a Canon repair center and they said there was nothing wrong with the camera. What an I doing wrong? I’m new to photography so maybe I using the camera wrong. Generally I have all nine focus points on but for isolated subjects I will use only one. I welcome any suggestions from everyone.

Donnie

[Joe Hoetzl]

Do you have any examples posted anywhere? It would certainly help to see what you are considering sharp vs. soft.
If you have them with the full EXIF data somewhere let us know.

As for the focus points question - there are several opinions on this one, for me, I usually leave center focus point on and focus/re-compose, or, just override the AF.

[inkista]

It's part of the learning curve with a dSLR that you can get fuzzy photos. :) Point'n'shoots are sort of optimized to not get fuzzy photos, but dSLRs allow you enough control to screw it up.

The first thing you might want to check is whether the fuzz is due to focussing or to shutter speed. If everything is overall equally blurry, then it's probably a focus issue. If you see streaks or multiple images, then it's shutter speed. It can sometimes be hard to tell the difference.

Whether you had the wrong number of focus points selected is pretty easy to tell--just open the photo up in the Canon software and have it tell you which focus point was used. Also, don't expect the autofocus to work as well in low-light conditions.

With shutter speed, the main rule is that the more you zoom in, the faster your shutter speed has to be to eliminate camera shake blur. You typically want to be at 1/focal-length (e.g., if you're shooting at 85mm, then you need to be at 1/85s or faster). To eliminate subject motion blur, it depends on the speed of the subject, but you typically want to use at least 1/60s.

You may also want to check your handholding technique (http://digital-photography-school.com/blog/how-to-hold-a-digital-camera/).

Lastly, you want to learn about aperture and its effect on depth-of-field (http://www.cambridgeincolour.com/tutorials/depth-of-field.htm). When you have a lens opened up wide, portions of the photo will be blurred, because only a limited amount of the image can be kept in focus.

[Donnie]

Thanks for responding to my question. I went back and looked at a bunch of my pictures. It seems that at shudder speed above 1/250 and apertures around f/8 they look pretty good. I guess it's the way I'm holding the camera of the way I push the shutter button.

Donnie

[smc1377]

Donnie, forgive me if my question seems insulting, but since you mentioned that you usually leave all the 9 focus points on, are you making sure that the camera is focusing on the subject you want to take a picture of?

I almost never enable all of the focus points. It's almost always on the center focus point. And like Joe mentioned above, I'll focus, then recompose if my subject isn't in the middle of the frame.