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Filmmaking improvements:

These improvements can be briefly summarized as follows:

- (a) Making two sensitive layers, double coating, the purpose of which is to resist the error that results from overexposure, by making two sensitive layers on the film support instead of one. The upper layer is susceptible to light, and the lower layer is less sensitive. If the exposure time is more than necessary, the upper layer with high sensitivity will be affected, and at the same time the lower layer will resist this error in exposure, as it will be affected to a very weak degree due to its lack of sensitivity, and thus we will get a negative image whose density is still reasonable. In this way, under exposure can also be overcome, as The highly sensitive top layer is sufficient to register the latent image in case of insufficient light.

(B) Over Coating the sensitive gelatin with a more solid layer. This method is followed with most of the sensitive layers. Its purpose is to protect the thin layer of gelatin from scratches that result, for example, from wrapping the films with some force, or from a precipitate in the acid that appears or is fixed, or from its friction with other tanks during the process. Show.

(c) Covering the support is another way to protect the gelatin layer from cracking. When the film is placed in the acidic acid, the gelatin layer swells slightly and then expands as a result of its saturation with the acidic appearance. And after the end of the display process and the drying of the film began, the gelatin layer shrinks to a smaller degree than its first state, while the support remains as it is without the liquids having any effect on it, which results in the film support curving inward (if it is celluloid). To overcome this situation, a layer is sometimes placed
A very thin layer of gelatin is placed behind the support and on the other side of the sensitive layer. And the shrinkage coefficient is equal to the shrinkage coefficient of the upper sensitive layer, so the degree of shrinkage of the two surfaces is equal and remains flat.


(d) A layer whose function is to resist the optical corona layer. It reaches the lower layer of the support, thus preventing it from being reflected back to the sensitive layer, so that no unwanted light reflections occur, which results in what may resemble the photoluminescent state. This colored layer has been prepared so that it dissolves easily in the water in which the film is washed before showing it, so that it does not adversely affect the color of the negative image.
And we show in the form of 66 sectors in a glass plate and another. In a film and a third in sensitive paper.


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