US1551611A

US1551611A - Color photography

Info

Publication number: US1551611A
Application number: US747828A
Authority: US
Inventors: Ollendorff Gerhard; Tanzen August
Original assignee: Aktiengesellschaft fuer Anilinfabrikation GmbH
Current assignee: Agfa Gevaert NV
Priority date: 1924-11-04
Filing date: 1924-11-04
Publication date: 1925-09-01
Anticipated expiration: 1942-09-01

Description

Sept. 1, 1925. Q 1,551,611

G. LLENDORFF ET AL COLOR PHOTOGRAPHY Filed Nov. 4. 1924 @dal R35 L A7-f# a4 l|||||||||||||||||||||||||||||||||||||||||| Fed/WWW a "I I l /Pea Vd/Qe/ovs/'/'Ve ummm-Emmimmmnm l l I Screen 5 fm1/.avian l &\\\\\\\\\\\\\\\\\\\\\\\w Green /r/Wrsr l Green fa/ae ,oas/'fire Screen Ema/nba Emu/Jion Patented Sept. 1, 1925.

y 1,551,611 PATENT oiFFlcs. A

GERHARD OLLENDOBFF, 0F BERLIN-WILIEBSDOBF, AND AUGUST'TANZEI, l0FY m- Lm-Tnnr'row, amm, assumons To nennt 1-: 1 rumxmrrcn, or 13mm, GERMANY.

' coLon rno'rocmmr.

`Application' led Iovember 4, 19M. Serial lo. 747,828.

To all whom 'it may concern.'

j Be it known that We, Galdiano OLLEN nonrr' and AUGUST TANZEN, citizens of the German Republic, residing at Berlin-Wilmersdorf, Germany, and Berlin-Treptow, Germany, have invented certain new and useful Improvements in Color Photography, of which the following is a specification.

This invention 'relates to the art of color photography.

In .methods known as polychromatic screen plate processes, for producing color photographs a considerable portion of light incident on the platepor film is absorbed by the rulings, grains or the like in the screen plate and thus the effective sensitivity ofthe" plate or film is diminished in proportion.-

This process is, therefore, not welly suited for such short exposures as are necessary, from the stand point of optical considerations, for Vthe photography of quickly moving objects.

For this reason,especially inthe production of colored cinematographic pictures, it is practice toresort to the use ofmonochromatic pictures, such as are obtained by exposing highly sensitized panchromatic fplates or films to the action of image-formlng devices in conjunction with appropriate light filters of the primary colors, as is Well understood, which pictures are then combined in well known manner to produce the composite color picture.

One method, according to which the 'three constituent color value positives are projected simultaneously,'so as to be in exact optical superposition upon the screen,

usually requires complicated apparatus.

Another. method, according to which the color value positives are lsuccessively projected, necessitates a relatively high speed ofthe film which is thereby subjected to undue strains.

It is the object of the present invention to Fig. 1 represents a colored object to be photographed;

Figs. 2, 3 and 4 represent three color value positives made therefrom; and

j Figs. 5, 6 and 7 the production of a composite color picture from the three color value positives shown in Figs. 2, 3 and 4.

The three color value n schematically represente in Figs. 2, 3 and 4 may be made in the usual manner and by any suitable apparatus well known inthe art. For the sake of illustration it may be assumed that a. represents a. positive that has been printed from a negative which was produced by a. camera and a red light filter. imilarly, positives b and c may be assumed :mummia itives a, b and c to have been produced in identical manner from negatives made with greenand blue filters, respectively.

The three color value positives are then photographed upon a polychromatic plate or film P, i. Ae. the pictures represented by appropriately illuminated color value positives as made in three color processes are superposed upon each other on the polychromatic screen, separately or simultaneously in any suitable manner.

Thisrmaybe done, as indicated in Figs. 5, 6 and 7 by contact printing. The three color value positives a, b and c are succsively brought into position upon a polychromatic plate or film P and illuminated by a suitable light source L in conjunction with the appropriate light filters al, b1 and c1, respectively.

While contact printing' has been specifically referred to as one mode of producing the composite colored picture upon a polychromatic screen, any other modes whereby appropriately illuminated color value positives may be photographed in superposition upon a polychromatic screen come the scope of the invention.

It is thus possible, by the present invention, to produce uniformly colored pictures of excellent color qualities which may be projected by simple projecting apparatus. Means for making accurate and pains-taking adjustments necessary for effecting exact superposition need be rovided only once and any large number o? colored films can be made thereby. Moreover, the accurate and tedious work necessary can be done at convenience and at ease.

We claim,-

1. The method of producing pictures which consists in malng color value ositives of an object and then photograp the color value positives, each illuminated by monochromatic light corresponding to in superposition u n a polychromatic screen provided on lts opposite side with a sensitive emulsion.

2. In the art of color photography, the step which consists in photogrghing color value positives, each illuminat by monochromatic light corresponding to it in superposition upon a polychromatic screen provided on its opposite side with a. sensitive emulsion.

3. In the art of color l1 tography, the steps which consist in ming color value positives of an object and then superposing pictures of the object as represented by the different color value positives, each illuminated by monochromatic light corresponding to it upon a. polychromatic screen provided on its opposite side with a. sensitive emulsion.

4. In the art of color photography, the

step which consists in super osing pictures of an object as represente by different color value positives thereof, each illuminated by monochromatic light corresponding to it upon a polychromatie screen provided at its opposite side with a sensitive emulsion.

5. Method of producing color photographs, which consists in photographing the composite ei'ects produced by color value positives, each illuminated b mono-A chromatic light corresponding to 1t, upon a polychromatic screen provided on its opposite side with a sensitive emulsion.

6. Method of producing color photographs which conslsts in making color value positives of an object and then printing the color value positives in succession, each by monochromatic light corresponding to it, upon the same surface unit of a polychromatic screen provided on its opposite side with a sensitive emulsion.

In testimony whereof we aix our signatures.

GERHARD OLLENDORFF. AUGUST TANZEN.