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Positive image color correction methods

There are two main methods followed in correcting the colors of printed or enlarged color images, and these two methods are:

(a) Color correction by subtractive correction. In this case, one light source is used, and in the path of the rays emitted by this source (which is directed towards the sensitive paper), light filters of colors: yellow, magenta, and cyan are placed for color correction. These filters are known as color correction filters (sometimes denoted by C.C. Filters). These filters absorb part of the light rays emitted by the source, i.e. they delete part of the components of these rays, hence the naming of this method as the “deletion method”, and it is sometimes known as the white light printing method. here

(B)

Colors by Additive Correction

According to this method, color correction is carried out using light rays of different colors, one of which is red, the second is green, and the third is blue, that is, they represent the three primary colors. In the end, we find that the effect that we obtained in the color image is a comprehensive effect as a result of adding each of the light rays emitted by these sources, which fall on the three sensitive layers of the colored film. In practice, it is usual for the light source to be one and the exposure to be done three times, and each time a filter is placed in the path of the rays, one red, the second green, and the third blue. This method is sometimes known by another name, Tricolor exposure. looking white rays,