Archived posting to the Leica Users Group, 2001/10/15
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]On Mon, 15 Oct 2001 11:54:00 -0400 Austin Franklin <darkroom@ix.netcom.com> wrote: > > So far I've been UV-filter-less for a year..... > > > > Walt > > Out of curiosity, did you notice your images were any better without the UV > filter? > > --Nah, but my use of the lenses is not as critical as say Erwin's... I shoot Tri-x or CN400 (various brands at EI250 or so)-HANDHELD- and print only 8x12.....there's NO way I could tell a difference in sharpness.... as for flare, without a strict A/B comparison, any conclusion would be anecdotal... As a note, when I was in college (photojournalism) we had a photo-physics class...I chose to "test" lenses for a project....I recall testing my then "beater" 50 f2 chrome, with some cleaning marks, dust inside, AND accidentally left a tiffen UV on it....now bear in mind that this was a "no-flare" setting, but still, the resolution exceeded our test charts at the distance we used!!! (I believe 125 lpm was the finest gradation on the chart, at the prescribed distance)....we used a Leitz (!!!) microscope at fairly low magnification (perhaps 50x?--it's been 20 years!).....to look at the resulting negatives-- Tech Pan (perhaps High Contrast Copy in those days)-I believe. The "on film" resolution is expressed as 1/total resolution= 1/max film resolution+ 1/max lens resolution. At least that's what I recall--hope it's correct! Point is, the lens resolution, with or without a filter, is only one part of the equation. If your camera is handheld at less than 1/focal length, there's NO WAY anything else matters....might as well be an Argus C-3. Most of my favorite photos, however, were shot under these conditions! (pushed tri-x, handheld, wide open @ 1/15 sec, braced on a chair or pole or whatever!!) As for increased flare, bear in mind that in the early days of coated lenses, then-active photojournalists thought that the UNCOATED lenses were better for available light!... the flare level "filled in" the shadows (pre-exposure, anyone?)...truly a case of practice NOT following science!... To each his own!....I might, however, still make fun of ya'll if you post something really dumb. :) :) ;) Walt - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html