Archived posting to the Leica Users Group, 2001/02/26
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]>Austin, >My problem with a lot of this testing is that it only measures the effect of >one variable - in your case, the effect of your filter on your lens, using >your camera and your film, etc. I think what needs to be done, is that once >you have somehow determined a difference between filter and no filter, you >need to place that in the context of all the other variables present when a >photograph is taken. >For instance, a test of a tripod mounted camera might reveal a slight >degradation of resolution when a filter is used. But the loss of resolution >when the same camera is used hand-held might be so great from the reduced >stability that any benefit gained by removing the filter is lost. >My experience with "scientific testing" of photographic equipment is that >you will get results that hold true for your equipment, your subject matter, >and the conditions under which you tested. They won't necessarily apply to >others. >Between the photographer's eye and the finished image, there are too many >variables to isolate a single one and evaluate it all by itself. Actually, there is a way to test more than one variable at a time and sort out the effects of each variable from each other and interactions between variables. It's called a Design of Experiment. If you're interested, let me know the variables and I'll set one up for you and analyze the data. At the end of the day, you should know the main effects and interactions. Ernie Ferro