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Print or enlarge color positive transparencies on Anskochrome "Brenton" films.

Anscochrome type Printon

The first is that it is possible to obtain opaque colored positive images by printing or enlarging the colored transparent positive images on special materials of opaque celluloid, and then dealing in showing them using the colored reversal method (1), without the need to go through the step of preparing colored negative images first. , as in this method that we are going now. Ansco factories were in the United States.

Hey

I made suitable raw materials for this purpose, and in 1945 produced what was then known as

Ansco's printon, then improved in 1956

New name: Anscochrome Type Printon

These raw materials are nothing more than a multi-layered colored film whose arrangement does not differ from the usual arrangement, except that the backing of this film is white and opaque. (ie not transparent). It is possible to store these materials at normal temperatures for months without fear of damage, and it can also be shown days after exposing them without fear of damage to the image inherent in them. These materials are characterized by their fast sensitivity, so if a lamp (50 (watts) is used in a magnifier and we wish to enlarge by three times Diameters, the image is transparent, colored, positive, of medium density, with an aperture

56 A on the amplifier, it suffices for that approximately fifteen seconds. These films are characterized by the fact that - after showing - they do not require any polishing, as their nature is very shiny. lens

(1) The information is more complete about the presentation of the reversal. Please refer to S. 356 in the book of acidification, printing and enlargement, the author, first edition - publisher: The Anglo-Egyptian Bookshop, 165 Street

Mohamed Farid in Cairo. (2) After that, Kodak factories in the United States and Agfa factories in Germany produced colored raw materials on a paper support to perform this opportunity, which is | It does not differ in its properties from Elvarsan Ektachrome films
It semantics. Brenton films should be shown in complete darkness or in a dark green safety light, and it is a mistake to project any direct colored rays on the film before the stages of the first show and the short stop.

The process of printing or enlarging on Brenton films: Similar to what we mentioned on p. These numbers are estimated based on the tests conducted by the factory after placing a filter that absorbs ultraviolet rays and another that absorbs heat in a regular amplifier illuminated by a 212 G.E lamp, the color temperature of which is 3000 Kelvin.

And since these numbers do not indicate a correct indication of all the filters necessary to correct the colors of the images because it is not possible to predict in advance all the factors that affect the correctness of the colors of the images (which are the factors previously referred to on p. required for color correction. To do this, follow these steps:

(1) Choose a positive transparent image with correct colors, or we use a Gery Scale, and either of them is placed in contact with the Printon film in the place of the enlarger-sensitive paper, in order to facilitate the use of the enlarger’s illumination after placing the filters whose numbers are shown on the envelopes of the films. It is possible to use for this purpose the same usual enlargement devices, assuming that they are equipped with a drawer to carry the necessary filters for color correction, and others to absorb ultraviolet rays and absorb heat (infrared rays).
(2) The colored positive image is printed four times, and each time the exposure time is different to obtain four experiments. The first experiment obtains twice the exposure required to obtain a good positive image on bromide paper, black and white with medium contrast, from a medium black and white negative with correct exposure and exposure. As for the following experiments, the second experiment obtains the same exposure time referred to above multiplied by 4 times, the third experiment multiplied, and the fourth experiment multiplied by 16 times. (3) Then we begin to show the tape of the film that bears these four experiments, and after showing it, we choose the one that has received the best exposure, so that this selected experiment will be a basis for studying the required amount of color correction. (4) Although it is not expected - except rarely - that we find this selected experiment correct in colors so that it does not require re-correction of its colors, but assuming that luck helps us in that, the next editions will not require modification, as long as we use the same film envelope. The image is considered correct in color if the colors of the grayscale image remain gray (neutral) in the image as well. (e) Here we say that the bases for color correction in these cases differ from the usual ones when printing from a colored negative to obtain a colored positive image, despite the fact that the filters used in printing or enlarging the negative-positive process are the same as those used in the positive method. Poitive Process. We have already mentioned on page 317 regarding color correction, if we are enlarging or printing a negative image to obtain a positive image, that is what is followed. Adding a filter of the same color as the smear to be removed, or reducing the density of the filters from the SMS exponent

The same color as the color of the smear. As for the positive-positive method, in order to correct or correct the following images, we must follow any of the following two methods:
(a) Adding a filter of a complementary color to the smear color. (B) or reduce the density of filters with a color consistent with the smear colors. For example. If we find that the first print prepared for color testing suffers from a blue tinge, then a yellow filter must be added to the group of filters prepared for color correction, or the intensity of the yellow filters should be increased, or the intensity of the filters that form the blue color (which in this case are the scarlet and cyan filters together) ). The density of the filters should be reduced or increased to an extent that suits the required smear density. removed. Perhaps one of the auxiliary methods for color correction is to use color compensating filters to look through experiments and reduce the

To find out the amount needed to be removed from the swabs.

Valid tools to show Brenton films:

Although it is possible to display these films in basins of appropriate sizes for the area of ​​​​the films to be shown, it may be preferable to use cut films display tanks. Suspension of these films on special metal brackets for this purpose (Fig. 75 p. 344), because the latter method does not entail any possibility of the images sticking to each other during the stages of display. However, it should be noted that the bleaching process should not be carried out in a metal tank, even if it is made of stainless steel (1).

jack. H. Coote - Color Prints-2nd edition. P. 237. (1) Of non-steel. This reference adds that it does not harm the film hangers to be rust-proof, because it does not result in any damage in the short period in which the film holder is dipped in the grouting bath tank.
D Pictures of what appears to us 1- The first manifestation: in a black-white appearance solution, and it follows that the silver salts (Silver Halides) are reduced to metallic silver, so three silvers are formed in the three sensitive layers, which are the negatives of color separation (Color Separation Negatives). And since the density of the final image and the extent of color balance in it depends on the accuracy of performing this first step, therefore. Clearly the importance of observing complete accuracy in it (1). 2- Stop bath: It would stop the reduction process. The second exposure: It is a necessary step to affect the silver salts that were not reduced in the first exposure process, so that they become capable of being reduced to metallic silver in the next colored exposure solution. Colored endorsement: In this stage, a positive silver image is formed in each of the three sensitive layers, accompanied by a positive dye image. . Bleaching: After a thorough washing in which all traces of the bleaching solution are removed, the bleaching process begins, which converts both images of silver into soluble silver salt. And these silver forms that we mean are the three negative images that arose in the three sensitive layers after the second colored display). Thus, nothing remains in the film except for the images of the three positive dyes that arose from the interaction of the products of the reduction process in the second colored display solution with the problems of color couplers inherent in the three layers. L

Demonstration steps: If we temporarily turn a blind eye to the intermediate washing steps, the basic steps become as follows:

6- Fixing the image:

Stabilizing colors: so that they do not settle in the future.

It is possible to show this film at a temperature of 75 Fahrenheit, and here the treatment time is reduced in the first backing solution to 9 minutes, and in the colored backing solution to ten minutes instead of what is shown in Table p. 398