Focus Confusion

[Jarrett-Nicole]

Hi everyone! I'm fairly new to digital photography and have been figuring out my Canon 40D basically by trial and error. I have a question and I can't find an answer to it in the manual because I don't speak "camera-ese" very fluently yet. Basically I want to know how I can get my camera to focus on the background and foreground simultaneously. For example: if I was taking a picture of people and a scenic background and I wanted both the people and the background clear. Is this possible? Also, can anyone point me towards a resource for translating photography jargon? Thanks in advance for your help and advice.

[bobwysiwyg]

Yes, you can do this, within reason. It depends on how far apart the subject and background are. You can accomplish this (both in focus) by selecting the correct f-stop, or aperture and checking with the depth of field preview button if you have one.

Normally, when you are viewing a picture before taking the shot, you are looking through a wide open aperture so the picture will be bright. If your shot calls for a smaller aperture for reasons of the correct exposure, it automatically stops down to that aperture just before the shutter opens to expose the picture. If you use the DOF (depth of field) preview button, it will temporarily stop down the the aperture you have selected to give you a chance to verify that all that you want to be sharp and in focus, is. Be warned though, the view will be much dimmer.

[TheWengler]

You can only focus on one thing at a time. The term you're looking for is depth of field (DOF). Stop down the lens (smaller aperture/larger fstop) to increase the depth of field.

[Mark_48]

Depth of Field - DOF

Start here.... http://www.dofmaster.com/dof_defined.html

And continue the adventure here.... http://www.dofmaster.com/articles.html

Some of it may get a little technical, but if you can grasp the basics, you're good to go.

Click on Virtual Camera, 2-aperature, and then try the demo. Adjusting the aperature ring on the lens will show how DOF is affected.
http://www.camerasinteractive.com/index.php#