Transcription: It may seem that color correcting filters add colors to a scene, but filters actually reduce certain colors by absorbing them as they pass through the filter. For example, when white light shines through a red filter, some of the blue-green light is absorbed and all the red light is allowed to pass through. A red filter will darken blue sky and green leaves and make the reds more apparent. And if the light source contains very little red light, the overall effect is to darken the image rather than to enhance the reds.
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