Originally posted by ckusnierek Is there any reading that would explain the relationship between DOF/Aperture/and Focal Length?
Do you want it the hard way or the easy way?
Here's the
Wikipedia entry on DOF.
The easy way: DOF is the range of distance from the lens where objects look to be in focus. Several variables are involved, but we can simplify it as:
* The shorter the focal length and/or the smaller the aperture, the thicker the DOF
* The longer the focal length and/or the wider the aperture, the thinner the DOF
Lens-to-subject distance is also a factor, as is the way the image is presented, and how good your eyeballs are. See the Wikipedia entry for details.
You'll hear about razor-thin DOF. That comes from fast (wide aperture) longer-than-normal lenses. Wide-angle (short focal length) lenses, with the aperture stopped down, may have seemingly infinite DOF.
And that's the short version. Have fun!