Re: Using 89B Infrared Filter with Regular B&W films

[v.bromfield@xxxxxxxxxx (Vaughan Bromfield)]

Folks

Regarding the "red filter not working" issue: when I first started out in
b+w I too couldn't get red filters to "work". The tonality always seemed to
remain about the same as an orange filter.

What I found effects the results is (in a rough order from memory, though
it's a while now) the way the neg is printed, ie grade and exposure;
conditions of the atmosphere which has already been mentioned and cannot be
underestimated (no effect on cloudy days, and on hazy too probably just as
much); and the exposure of the film.

When printing images with red filters that I know will make the sky black,
I expose the paper for the dark sky and adjust the grade paper to fit the
highlights in nicely and appropriately.

As mentioned, strongest effect is 90 degrees to the sun: with my 21mm lens
(90 degree view) a red filter will actually produce a gradation from almost
black to about mid grey in the sky.


Vaughan



>On Tue, 11 Feb 1997 07:09:15 GMT, Sue Myers wrote:
>
>|I just shot a roll of T-max myself, for my photo project for a Graphic
>|Comm. class I'm taking. . . I have a cokin red filter (#3?) which is the
>|equivalent of a Wratten 25, and the shots I took with the filter look =
>very
>|similar to those taken w/o the filter. I took them last Friday, on an
>
>This post, plus the earlier similar comment, is very puzzling to me.
>Perhaps that's because I've never tried using T-Max films for
>landscapes, but it certainly goes against the grain of both
>conventional wisdom (is that an oxymoron?) and my own experience with
>regular panchromatic films.
>
>According to "the books," panchromatic films render the visible
>spectrum more nearly the way we see its values than do orthochromatic
>emulsions (which are notably weak in the red range), but pans still
>don't have the hypersensitivity in the yellow-green that the human
>retina does.  The recommended "correction" is usually a light yellow
>or yellow-green filter.  A dark yellow filter goes beyond correction
>to make deep-blue skies look a little darker, and therefore more
>dramatic, than they do to the eye.  An orange filter is supposed to
>take this tendency a bit farther, a light red filter a bit farther
>still.  By the time you get to pan film with a Wratten 25 (dark red)
>filter, the effect is supposed to be "very dramatic," partly because
>it's blocking off the blue light in which shade and shadow areas tend
>to be rich, and thus yielding "increased contrast."
>



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