The use of color filters

Remove dust

In nature, the atmosphere is filled with a large number of very small dust and water vapor, dust formation. The sunlight in the blue and purple lines through the fog, a large number of scattering, the distant scene a hazy state. The farther the distance, the greater the degree of fuzziness. In this case, such as shooting distant scenes, because the photographic film is very sensitive to dust spreading in blue and violet light line, captured by the distant scenery image is not clear enough.

In order to make clear image can reach the distant scene, you need to choose to absorb and weaken blue and purple color. Generally speaking, the darker color of yellow, orange or red filter can absorb dust scattering in blue and violet light line, so as to get a clear image of distant scenery.

Adjust contrast

Because of the difference of photographic film of spectrum in various colors of light sense of color performance, the different colors of the scene, after the exposure reflected in the photo on the black, white and grey tone shades each are not identical, performance for lack of contrast or contrast is too strong. In photography, sometimes to a part of the scenery on the color can be adjusted, niches it reflected the tone in the photo can be strengthened or weakened, you need to increase or reduce the throughput in this part of the light using appropriate filters. This is the use of filter contrast adjustment.

Captured during winter with blue sky and green pine trees in the snow, snow and the blue sky, green trees contrast very disparate, such as with green filter, the contrast of the harmonization of the effect was obtained. As with panchromatic film shooting at the end of the yellow of the scarlet letter, objects, through the yellow light green color filter, can make the bottom of the yellow is bright, blackening the scarlet letter, the handwriting is very prominent. On the contrary, such as red and yellow light can pass through the orange, red filter, weakening the contrast, the yellow, red two colors were light grey, the handwriting is not obvious. Shooting portraits in the sun, in order to adjust the characters facial luminance and sky brightness contrast, often with yellow filter lens, the normal tone was obtained.

Show the sky

Photography in outdoor activities, most of them cannot do without performance on the sky. Blue sky and white clouds and the sky bright clouds tend to make a common scenery photos hyperchromic brilliance; in everyday shooting commemorative photos of people also like "the blue sky floating white clouds" as the background.

For the performance of the blue sky and white clouds, with a yellow filter, the blue sky and white clouds light absorption effect, but to in the sky blue, violet absorption prevent more. In the photo showed deep dark gray tone; absorb less light towards the white clouds, the Baiyun in the photo on the dark grey in the sky appear outstanding.

If added with orange and red filter to the performance of the sky, the sky darker. The clouds are more prominent, but often give people an unnatural distortion feeling. So in general, should not use red, orange filter performance of blue sky and white clouds, unless it is to create a special artistic effect.

Reject color

In shooting a colored object, such as the need to will among them a kind of color to eliminate or reduce, selection and the same color filter, to eliminate the color through a lot, in the picture is white, the elimination of the role. Such as shooting contaminated with a certain color items, would like to eliminate pollution of color, combined with filter and the color of the same, can obtain satisfactory results.

Color correction

Sometimes with black and white film in light under the condition of shooting, because light red, yellow and orange too much, blue, purple too little, according to need to add the blue filter absorb too much red, orange light, relative to make up for the lack of blue and purple light. During the filming of the red leaves, and red color, dark green leaves and bright flowers; therefore, dark leaf ming.

In order to make the scene of a variety of colors to color photographic film to achieve color balance, often choose the school color filter to correct the color in color photography.

Special effects

In the outdoor strong sunlight, using panchromatic film and with deep red filter, the moonlight was obtained, such as the crimson color filters and polarizers combination, to further strengthen the atmosphere of the night. Shooting in the movie, is frequently used to create outdoor night effect.

Reduce brightness

In some light clear the environment, such as beach, snow, desert and other occasions, although exposure limit has been reached (i.e. aperture has been contracted to the minimum level, the shutter speed is also adjusted to the fastest file, in photography and film speed is fixed), is still unable to do so properly exposed, in order to make the brightness of the scene to exposure, you need to use the can reduce the brightness of neutral grey filter, scenery of the generally lower, to exposure to the luminance adaptation. Sometimes in order to reduce the brightness of the sky or background, often using half neutral gray filter is locally reduced brightness, make ground scenery brightness invariant. This reduced brightness of the neutral gray filter is indispensable in the film photography.