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Although
originally intended for use with black and white film, these
filters can also be used as a creative tool in color
photography.
Black and
white imaging records only tonal differences between colored objects, which
appear as black, white, or different shades of gray.
Proper rendition depends on your own desires, and, for film, the
differences between film sensitivity to colors and that of the eye.
The latter is due to the fact that most panchromatic emulsions used are
more sensitive to blue, violet and ultraviolet than to other colors.
Therefore, blue appears as lighter on film than it does to the eye. This can make a blue sky light enough to appear a similar
shade of light gray as the clouds that are in it, making the clouds
"disappear." A more
"correct" cloud presence is obtained through the use of a yellow
filter, such as a Wratten #8, which
can absorb blue light, darkening the sky to more closely match what the eye
would see. The #8 also acts as a
general compensator for most subjects, giving a tonal rendition similar to
that of the eye. Deeper colors,
further to the red end of the spectrum, such as Wratten #15 deep yellow, #16
orange, and #25 and #29
red filters will produce progressively deeper and artificially more dramatic
renditions of blue sky.
Remember
that, since these filters act on color differences to produce tonal
differences, the required colors must be present.
The part of the sky you are recording must be blue to be affected.
Sky sections closer to the sun, or nearer the horizon, are generally
less blue than elsewhere. Use of a gradated neutral density filter can darken a sky
relative to the foreground, but will not increase contrast between a blue sky
and the clouds. In most
situations where color-contrast and tone adjustment is involved, these filters
work similarly for black-and-white video as for film.
Using filters
for contrast control can be a matter of artistic preference, or of necessity.
It is possible for two disparate colors, say a certain orange and blue,
to record as the identical tone, eliminating any visible difference between
them. Filters will lighten
objects of their own color and darken those of their complement.
Complementary color pairs are: green-red; orange-blue; violet-yellow. An orange filter in the above case will darken the blue, and
lighten the orange; a blue filter will perform the reverse.
A green
filter, such as Wratten #11, can be
used to lighten green foliage, to show more detail.
It may also be used to provide more pleasing skin tones outdoors,
especially against blue sky.
Any filter
used for the above purposes will have a greater effect if slightly
underexposed. Its function
depends on absorbing light of its complementary colors to increase the
proportion of light of colors similar to itself.
Exposure compensation is often needed to allow proper image density,
but the relative difference is reduced by the addition of light at the
absorbed wavelengths through additional exposure.
Other filters
for black and white photography include:
Yellow 12:
"Minus blue" cuts
haze in aerial work; reduces excess blue of full moon in
astrophotography. Recommended as a basic filter for use
with Kodak Aero Ektachrome Infrared film.
Orange
21: Absorbs blue and blue greens. Renders blue tones
darker as in marine scenes.
Green
58: Dark green filter that produces very light foliage.
Red
23A: Light red filter producing contrast effects that darken
sky and water, as in more dramatic architectural
photography. Not recommended for flesh tones.
Blue
47: Dark blue filter that accentuates haze and
fog. Used for dye transfer and contrast effects.
Blue
47B: Dark blue filter that lightens blue objects for
detail.
The Tiffen Company, LLC
90 Oser Avenue, Hauppauge, NY 11788
www.tiffen.com email:
techsupport@tiffen.com
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