So, how does one measure ease of focusing in a lab? How does one measure comparative ease of focusing (say a 35mm lens v a 105mm lens)? What tests are used, what equipment is used? How do you define "ease?" Is the lens tested on a camera, or is the camera something that gets in the way of an objective test? Is there an "easy of focusing" machine to which the lens is attached? Do you use more than one sample of each lens? Do you change the light at times, vary the subject? Is there an "ease of focusing" test target? How does the target relate to real world subjects? For example, does the lab target have a face? A nose? Eyes? Wear glasses? Or is it some flat sheet of paper with grid lines on it?
Shel > [Original Message] > From: Cory Papenfuss > > Perhaps those of you relying on science and physics should pick up a couple > > of appropriate lenses, stick 'em on your istD or istDS, and see what your > > results are instead of quoting the laws of physics, which you did with a > > large list of qualifiers. > > > > Shel > > > I trust physics and measurement equipment more than my own > subjective opinion since I know my opinions can be swayed by unrelated > factors. Don't even get me going on tube (valve) audio amps vs. > solid-state.... -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
