Depth of Field Aperature and size of elements. Read Edward Weston's diaries from Mexico if you really want to see that the greats stumble around like the rest of us. Weston had large aperature portrait lenses. Big (macho) glass. He kept trying to stop down to get more and more sharpness and depth of field. Didn't happen. We all know about refraction and optimal aperature (yawn) A big part of Weston's problem was his lenses were too big. large glass, very fast large aperatures. Great for portraits (some even had soft focus widgets) I just shot some paintings for a client I used my 180 Apo Fujinon lens f 9 for the 4x5s and a rented 350 Schneider something or other f5.6 for the 8x10 trans. The Schneider got beat. Not because it is bad, but because there was just too much glass. The Schneider isn't a bad lens, it just isn't designed to do copy work. Very sharp lenses for copying are usually tiny more easily corrected pieces of glass. The small glass reduces internal reflections. Weston tried cutting little pin hole aperatures in paper and inserting them into his lenses. A dentist finally pointed out the problem of too much glass and Weston went out an bought a slow, small and sharper Kodak lens for $15. Modern lens design and coatings eliminate a lot of this. ---William Nettles [EMAIL PROTECTED] Nettles Photo / Imaging Site http://www.wgn.net/~nettles _______________________________________________ Cameramakers mailing list [EMAIL PROTECTED] http://rmp.opusis.com/mailman/listinfo/cameramakers
