P3D Filter Quality

[markaren@xxxxxxxxx (Karen Obusek)]

A filter mounted over a lense does not appear to affect the image
quality. The filter only need allow the light to pass through and the
image is resolved at the film plane. Here is an extreme example ( and
why I don't believe there are noticable quality differences in filters)
Taking the blister plastic wrap from my new Bogen slide bar, and
cleaning it off.....I placed the plastic very close to my eye and took a
look through it. I did the same with a couple of sky 1A filters. I COULD
NOT tell the difference between the piece of plastic and the filters! As
I moved the plastic away from my eye as I continued to look through it,
the flaws and abberations in the plastic became noticable. I concluded (
to myself...I'm sure others will think I'm blind) that the distance
between the filter and lense is a factor that has not been considered. A
filter that is viewed through and included within the DOF focusing range
would be likelier to reveal quality differences than a filter mounted at
the lense. Perhaps I need a scientific explanation.........or another
beer! :-)
                                  
                                          Mark Dottle


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