Stop-D

 
The F Stops Here
The title is a bad pun, I know, but I couldn't help it. (My second choice pun is found in the subtitle).
There has been arecent discussion(July, 2002) on theDiscussion Forumthat evolved into one about the resolution of lenses; wide open Vs. stopped down.; aerial image Vs. image resolution on film, etc, etc. While this is of interest, it raises the practical concern that all photographers have about using their lenses at optimum aperture Vs. stopped down.
Most photographers know that lenses typically perform at their best about 2 stops down from wide open. This is usually at f/5.6 or f/8 (depending on the maximum aperture of the lens). Using the lens either wide open or stopped all the way down can lead to increased aberration, diffraction effects or facial warts. Somewhere in the middle is best. Right?
We all believe this, myself included, because it's mostly true (except the part about the warts‚ I made that up).But is it relevant?!
Chained Hut‚ Iceland, Jun...