Depth of field

[jbenenson]

Hi,

I was surprised to learn (through the forum) that the G3's minimum aperture is f8. Being new to digital cameras (the G3 is my first), I was wondering how this affects the depth of field. I know that the lens focal lengths are expressed in "35mm equivalents" and the aperture is a ratio of the actual focal length, so is there an equivalent 35mm minimum aperture, or is f8 really the minimum? If that's the case, then depth of field is really limited IMHO.

[JamesC]

f8 may seem a relatively large minimum aperture, especially compared to f22 on 35 mm lenses, but the thing to remember is that it is the actual focal length, not the '35 mm equivalent' that determines the depth of field. So the G3, with its short actual focal lengths, usually has massive depth of field (sometimes almost too much: I really like throwing backgrounds out of focus, and it can be difficult with the G3).

See http://dfleming.ameranet.com/dofjs.html for a useful depth of field calculator.

[jboyd]

check out this article on depth of field. You may find you like the website, too!

http://canong2.dynip.com:8080/canon-g2/digital-darkroom-article28.shtml

Jackie