Re: [Leica] Filter Degradation

[Steven Alexander <alexpix@worldnet.att.net>]

> 
> Here is my problem. After reading Tina, Ted and the gang on the light
> bending and brightness- diminishing effects of expensive, high-quality
> optical glass I wonder what insidious effect I create by hanging that square
> of cheap plastic in front of my Hassy lenses.
> 
> Anybody have an opinion?
> 
> Thanks.
All this talk about the degradation of image quality due to the usage of
filters has finally prompted me to write this.

As a cinematographer, 20 years shooting documentaries, commercials, non
theatrical and theatrical films, I can truly say that only on a very few
occasions did I fail to have a filter of some sort in the optical system
path.  16 mm film image area is considerable smaller than 35mm still  image
area as is 35 mm film area and the projected image (in most cases second or
third generation) must be made from the best quality original negative, I've
never heard this argument among cinematographers.   In twenty years of
reading the Journal of the Society of Motion Picture and Television
Engineers or American Cinematographer or meetings of IATSE cameramen,  I do
not recall any such warning telling people not to use filters.

The people who create filter, Tiffen, Hoya, Lee, B+W, Harrison and others
never address anything about degradation of image other than the damage to
the image caused by non optical quality material.

As a still photographer, doing color travel stock, I use filters on almost
all the images that I create and again the ASMP or other professional groups
never seem to be concerned about this "issue".

Filters are just another tool.  If your handheld meter shows a measurable
difference with or without the filter, I wonder what effect would be
measured by transmission measuring device.  Please consider the effect a
variation in time, temperature or agitation will have on you exposure index
as well as improperly taken handheld meter readings of a scene.

Happy snaps,

Steven Alexander