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.
FILTERS FOR COLOR
General Information
Recording color involves knowing more about light sources than is necessary for
Knowing that light is a form of energy, we can theoretically view it as energy emitted from a hot object, usually termed a 'black body,' that gives off light as a function of its temperature. The color of that light can be measured in degrees Kelvin (K). The normally encountered types of light can be categorized by certain anticipated color temperatures, or can be measured with a color temperature meter.
Color Conversion Filters
Color Conversion filters are used to correct for sizable differences in color temperature between the film and the light source. These are comprised of both the Wratten #80 (blue) and the Wratten #85 (amber) series of filters. Since they see frequent outdoor use, in bright sunlight, the #85 series, especially the #85 and #85B, are also available in combination with various neutral density filters for exposure control.
Light Balancing Filters
Light Balancing filters are used to make minor corrections in color temperature. These are comprised of both the Wratten #81 (yellowish) and the Wratten #82 (bluish) series of filters. They are often used in combination with various neutral density filters for exposure control. They are often used in combination with Color Conversion filters. Certain #81 series filters may also be available in combination with various neutral density
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