DOF Help?

[ezb]

Firstly I'm basicly a novice to photograhpy, I know bits and bobs, I've been trying to mess around with DOF, I think I get the bases of it, but it seems my camera (350d stock lens) doesnt, I believe that the number on the right hand ride of the dial seen in the viewfinder is the focal length? mine seems to be stuck at 9 :rolleyes: no matter how I change the apeture my camera seems to keep the photos the same. I have two choice, everything focused or macro like shots. Been through alot of tutorials but my camera does not seem to respond.

Hope someone can help, cheers for reading

[John_B]

ezb,
Try putting your camera on Av or M and then you will be able to easily change the aperture. I believe the number you see is how many photos you can take to fill up the buffer. If its similar to my 10D the shutter speed and f/stop is on the left side of the viewfinder.

[ezb]

Just looked it up, yes your right, no idea where I got that from then..... unless theres something alike? I am using M and Av when doing this, sorry should have said that to start with. The thing I was thinking is what sort of lenghs my camera would focus on, I was hoping the stock lens would allow me to focus on a subject a short distance away and blur the background? I've had one slight success with this seen here (http://img441.imageshack.us/my.php?image=img2184qf2.jpg) but this is the only shot to come out like that.

[John_B]

ezb,
Ok we are making progress :)
I assume your lens is the 18-55? ???
Depth of Field is much larger with wide/ultra angle lenses. The best you can do is use your largest aperture at your longest focal length (ex. 55mm f/5.6). A cheap alternative is to pick up a 50mm f/1.8 lens (its only about $80) and with an aperture of f/1.8 you can get really small DOF and lots of blurred background.

Here is a link to DOF calculator which you can put your lens, aperture, camera and subject distance to show how much will be in focus at those settings Online Depth of Field Calculator (http://www.dofmaster.com/dofjs.html)

[ezb]

Yeh, using the 18-55, I get how it works, just doesnt seem to :P if I wanted to focus on a subject say 5/10 feet away, using this standard lens what aperture range would I be looking at?

cheers for your help