DE163282C - - Google Patents

Description

ΌΐΛψψ

IMPERIAL A

PATENT OFFICE.

M 163282 CLASS 57b.

by means of a recording.

Method of making three negatives for three-color photography by means of three Recordings that follow one another in time are known, as are those for simultaneous recordings Production of three recordings by means of three lenses, as well as by means of one lens, whereby the light beam behind the lens is split into three parts by mirrors or prisms will. Finally, a method is described in the English patent specification 28920/1897 in which only two recordings are necessary. With one of the two recordings two negatives are produced simultaneously by layering two photosensitive plates to be exposed to layer so that the back layer lets its light through the front receives. A color filter in the shape of a membrane is placed between the two layers inserted. The third negative is

ao recorded in a known manner through a color filter.

The last three methods have not yet found any major practical use. Only the first method is used extensively. For taking pictures of objects that are not completely still, as well as for the use of the lover, however, it is too difficult and cumbersome. The same is true, if to a lesser extent, of the last-mentioned procedure.

The invention described below aims using the ordinary photographic apparatus with one recording to produce three negatives, in which the colors of the subject are registered so that they match one of the known Three-color process can be reproduced. There are three light-sensitive layers lying one behind the other, each of which is arranged on a special image carrier, exposed at the same time, so that the back layers receive their light through those in front. Here, as with any three-color process, it is necessary that with each individual. certain rays of the three layers are excluded from the effect. this happens according to the present invention in that a layer is used as the foremost layer which is insensitive to the rays to be excluded, in conjunction with a second which is only for part of the to be excluded rays is insensitive, while the rest of these rays through upstream Dye is absorbed, and finally in connection with a third, which is not marked insensitivity shows against certain rays, with which then the exclusion of the rays concerned is achieved solely by upstream dyes. Here the third layer can go through one by the properties of the second and the second by one of the Properties of the first are replaced, if it succeeds, layers of the required To establish insensitivity to the specific rays.

In the combination of three such layers

Claims (4)

to a recording plate in which the insensitivity of these layers for certain types of radiation with the absorption capacity of certain dyes for certain types of radiation are combined in such a way that, by means of one recording, three are used for the known Negatives suitable for three-color processes result, the essence of the present consists Invention. ίο Using already available in stores Material, the practical implementation of the process is as follows. A commercially available chlorobromide silver plate serves as the foremost layer. It is predominantly sensitive to blue, not very sensitive for red and even less sensitive to yellow. So it serves to absorb the blue-violet rays and gives the negative for yellow printing if a subtractive positive process is used. For red printing, one is sensitive to green Shift required. Such layers can be removed in a known manner by bathing Achieve bromosilver gelatine in red colorings (erythrosin, eosin). Here, however, remains the original sensitivity to blue of the bromide silver predominantly. To be sufficient To achieve a predominant green effect, a color filter is required here, which attenuates the blue rays. In addition is a light yellow, which is used in the form of a celluloid or gelatin skin Can be found. On the first mentioned silver chlorobromide plate, which with the layer after is exposed at the back, the yellow filter follows and then the red-colored one, that is green-sensitive layer, expediently in the form of a very thin film (layer after rear). The red colored film now forms an orange filter together with the yellow filter, which absorbs blue rays very perfectly. The one to be used as the third layer The silver-bromide gelatine plate must now have a high red-yellow sensitivity, whereby an incidental blue sensitivity does not interfere. This plate comes with the layer side facing forward on the film and expediently with the front glass plate connected at the edge by glued-on paper strips. For the last layer, those available in stores are suitable Ethyl red sensitized silver bromide gelatin plates. Note the increase here the sensitivity of the three layers from front to back. The first layer has the lowest sensitivity, the rearmost the highest. The exact mutual adjustment the sensitivities is achieved by correspondingly darker or lighter layers of color. It is advisable to remove the yellow filter formed from a yellow membrane by coloring the front layer with a to replace yellow dye. This brings the light-sensitive layers closer to each other, and if the right choice of dye is used, an increased Blue and red sensitivity of the front layer. Acridine orange is a suitable dye NO. For the second layer, however, it is recommended to use the red dye, which serves to raise awareness, not to apply so concentrated that the second layer itself forms the red filter, because it increases the overall sensitivity and the green sensitivity the middle layer suffers as a result of absorption of the green rays in the gelatin. A special red filter, consisting from a red skin, is preferable. The already existing blurring of the rear The partial image is enlarged a bit, but it remains like the experiment shows within the limits that allow a good image effect. The image carrier of the middle layer can also be colored red so that it replaces the filter. In the arrangement described, the front and the middle partial image are reversed. Since the middle one rests on a film, it can be made the right way round by reverse copying. The front one must go however, they can be reversed by one of the known reversal methods. However, you can also use the front image carrier use a film or also for the rear; one then uses appropriately for Pressing the same a glass plate without a layer. As an example of the implementation of the method with the currently known materials let the following be given: Front layer: Ertee - silver chlorobromide plate, sensitized and colored with acridine orange NO. Middle layer: Agfa roll film, sensitized and colored with eosin yellow. Back layer: Lumiere plate (nouvelle extra rapide; purple label), sensitized with Orthochrom T (Eder, yearbook 1903, P. 307). Godfather ν τ-Α ν Proverbs: i. Process for the preparation of three negatives for three-color photography by means of a picture, characterized by the simultaneous exposure of three each resting on a special image carrier, light-sensitive layers arranged one behind the other, of which the rear have a correspondingly higher sensitivity than the front ones, and of those the foremost layer for those of the The effect of the rays to be excluded is insensitive, the second layer only for some of the rays to be excluded is insensitive by the remaining rays to be excluded passing through upstream dyes are absorbed, and none of which the third layer shows pronounced insensitivity to certain rays by doing this ίο all rays to be excluded are absorbed by upstream dyes. 2nd embodiment of the method according to claim ι, characterized in that the for complete or partial absorption the dyes serving to exclude rays are incorporated into the photosensitive layers themselves, so that the front layers form the light filters for the layers behind, whereby at the same time the incorporated dyes to increase the sensitivity for certain Can serve radiation genera. 3. Combined receiving plate for performing the method according to claim ι and 2, characterized in that the foremost light-sensitive layer a silver-bromide or silver-chlorobromide plate of minor general and predominant Blue-violet sensitivity with a yellow colored layer (glass side facing forward) as a second light-sensitive layer a film with a slightly higher general sensitivity with a red colored layer (film side forwards or backwards) and as the rearmost layer a red-sensitive bromide silver plate of high general sensitivity (layer side facing forward) are placed on top of one another. 4. Combined receiving plate according to claim 3, characterized in that instead of the front or the rear glass plate, a film is used which is pressed through a glass plate without a layer will.