التصوير الملون وفقا لنظرية الإضافة ..كتاب التصوير الملون ، الكاتب عبد الفتاح رياض

Color photography according to the addition theory using color sensitive films with mosaic filters inside them, Mosaic Screen Films

This method is based on the theory of the formation of colored images by the additive method, in which a panchromatic sensitive film (sensitive to all colors) is used, and between the support and the sensitive gelatinous layer a very thin layer of transparent colored materials (colors: red, green and blue) is carried between the support and the sensitive layer of the rays. ) This layer is known as the Mosaic Screen or another name sometimes is Reseau

Figure (40), which controls the color of the rays that penetrate the sensitive layer

Panchromatic at the stage of exposing the film in a camera, so it performs the same function as color separation filters (red, green, and blue) Color Separation Filters, which we have already talked about on p. 113). Thus, this single film that we are dealing with now is an alternative to the three films on which images are composed

Color Separation Negatives

Displays the flag of this games

Celluloid backing

adhesive layer

Colored starch granules

Waterproof coating

The o-nechromatic layer is sensitive

(B)

(Fig. 40) Mosaic filters

It shows the colored starch granules that are the elements of the colored mosaic filter in the Lumiere Film Color Film, and in every square inch of the film there are approximately

of 4 million granules. Figure B: shows a section in the previous film.

The transparent resin layer may be in the form of colored lines divided in an geometric way (1) and printed in a mechanical way (Fig. 41), or in the form of very fine granules of dyed starch or wax (Fig. 40). And . The spaces occupied by all the colored elements that make up the filter must always be equal.

As a result of the studies (2) conducted on the filter carried by this type of film, it was found that if the mosaic filter is divided according to a regular geometric shape, then it is sufficient for the width of the lines to range between . To - of an inch, but if the filter is composed of irregularly shaped granules, then the previous limits must be reduced to between (m - pim of an inch). And since spaces are likely to exist between the elements of the filter if it is of the second, irregular type, so the makers of these films work to fill them with materials that have a great ability to absorb radiation. Thinking about making this type of film began in 1868, and many researches and experiments followed, some of which failed, while others succeeded and were produced on a commercial scale, such as the sensitive plates that were known at the time as Lumière Autochrome plates, and in 1909 they were followed by the Finlay process, and in 1916. It manufactured Agfacolor screen plates, and in 1932 it produced Agfacolor screen films, then Lumière alticolor, and in 1953 the Johnson color screen process appeared, and in 1957 the production of Dufaycolor films, which began in 1936, was halted. The film carried inside it a regular-shaped mosaic filter consisting of blue and green squares separated by red lines (Fig. 41). And in

(1) Fuller information on how to make this mosaic curtain is due to Adrian Cornwell Clyne Color Cinematography P. 284 (2) Evans. Principles of Color Photography P. 287 Mess & Pledge These studies were carried out by:

By placing a negative film in the camera, it will be exposed after exposure, then the negative image will be printed on another positive film, the order of the layers of which does not differ from what we previously showed in (Fig. 42), and after displaying the positive images become valid for projection on the screen. Two types of negative films have been prepared: in the light of industrial sources whose temperature is 3000 Kelvin. - And another type prepared for imaging in electric light, High Intensity ares (6000 Kelvin), and neither of the two previous types requires the use of any optical filters (a-1, one of them for color imaging). Daylight or arc while shooting

(A) For photography, the negative is the positive » Negative Positive

(B) Reversal photography: The films were of a size of 16 mm intended for cinematography or small, rolled films prepared for color slides, and the types intended for photography in daylight do not require the use of any light filters, as for those needed for photography in light. There were special filters made by producers for these films. This and none of the previous films have the degree of tolerance that we are used to in “black and white photography”, so the exposure should have been estimated very correctly, with caution against the extreme contrast in lighting unless this was for a special effect desired by the photographer.

The following reference is mentioned:-

Cornwell Clyne - Color Cinematography Ist. edition (1)

If there is a film of Mauna of this species known as Mondiacolor carried per square millimeter

1800 elements of the mosaic filter, which are located in four colors (and we do not have sufficient information about it). (2) For more information about showing films using the reversal method, refer to the book “Development, Printing and Enlargement” by the author (pg.