Table 1-1. Wratten filter designations
c. To make pan film exposed to tungsten light respond like your eye, you must reduce the blue
which the pan film is sensitive to and reduce the red of the tungsten light. So you should use a light
green (No. 11) filter (Table 1-2).
Table 1-2. Tone-correcting filters
Filters emphasize one color.
a. It is possible that two different colors reproduce the same shade of gray in a black and white
photograph. If your subject and background normally reproduce similar shades of gray, even though the
colors are different, you can make the subject stand out by using the proper contrast filter to lighten or
darken a particular color.
b. Use a filter the same color as the subject you wish to lighten.
c. Use a filter the complementary color of the subject you wish to darken.
d. As an example, suppose you have red letters on a green background, but there is a very little
contrast on the black and white print. A cyan or green filter will darken the letters and lighten the
background; a red filter will lighten the letters and darken the background.