US1871479A

US1871479A - Color photography

Info

Publication number: US1871479A
Application number: US357270A
Authority: US
Inventors: Tarbin William Thomas
Original assignee: Agfa Ansco Corp
Current assignee: GAF Chemicals Corp
Priority date: 1927-02-01
Filing date: 1929-04-22
Publication date: 1932-08-16
Anticipated expiration: 1949-08-16
Also published as: GB283765A; FR647571A

Description

, 16, 1932- w. T. TARBIN 1,871,479

COLOR PHOTOGRAPHY Original Filed Jan. 21, 1928 im'qifiiffii" lIlllllllllllllllllllllllIllllll' BLUE Patented Aug. 16, 1932 UNITED STATES PATENT; OFFICE WILLIAM THOMAS TARIBIN, OF ECCLES, MANCHESTER, ENG-LAND, ASSIGNOR, BY ASSIGNMENTS, T AGFA ANSCO CORPORATION, OF BINGHAMTON, NEW YORK, A

CORPORATION OF NEW YORK COLOR PHOTOGRAPHY Original application filed January 21, 1928, Serial No. 248,391, and in Germany February 1, 1927. Divided and this application filed April 22, 1929. Serial No. 357,270.

This invention relates to the method of color photography, which expression as used herein includes color cinematography, and photo-mechanical color printin processes,

for example the half-tone, intagho, collotype and like processes of pictorial reproduction in substantially natural color, by the exposure simultaneously of a plurality of superimposed layers of light-sensitive composiwhen superimposed will form a composite representation of a subject in substantially its natural colors.

Usually the number of superimposed layers of light-sensitive composition employed and the number of differently colored photographic images which are arranged in superposition in processes of this kind are two or three, the process in the one case being descrihed as a two-color process and in the other case a three-color process.

Hitherto, processes of the kind in question, using a plurality of superimposed layers of light-sensitive composition, have not given wholly satisfactory results owing, firstly, to the lack of definition or diffusion of the image due to the scattering of light by the several layers and their supports and, secondly, to

the length of the exposure needed in forming p the negative.

The object of the invention is to provide an improved roll film of the kind referred to which shall not be open to the above-stated objections inherent in the prior proposals.

The invention is based upon the observation thatthe layer of light-sensitive composition which is selectively sensitive to the rays situated towards the blue end of the spectrum should be located in making the exposure to obtain the negative images farthest from the source of light. V

A bromide emulsion of high sensitivity will normally be used as the layer of light-sensit1ve composition sensitive to blue in place of the chloro-bromide emulsions previously employed for forming the blue sensitive layer in the known processes.

' Where the invention is applied to the threecolor process it would seem relatively immaterial whether the layer of composition sensitive to red or green is arranged immediately The several layers of light-sensitive com-.

position may be associated with a transparent support or transparent supports in a variety of manners. In some cases it may be desirable or even necessary to employ layers of composition which may be stripped from the support; for example, in the three-color proce'ss the layer of composition sensitive to red may be in the form of a stripping film attached to a transparent support such as glass or celluloid while the layer of composition sensitive to green and the layer of composi tion sensitive to blue are non-stripping films on suitably transparent supports. The invention will be described in detail and by way of example with reference to the accompanying drawing, in which Figurel is a diagrammatic view of a camera adapted for taking cinematograph pictures or single pictures as desired upon three separate light sensitive films, while Figure 2 is a perspective view of a composite spool of film in accordance with the invention adapted for use in hand cameras.

Figure 3 is an enlarged sectional view of the composite film illustrated in Figure 2.

Referring to Figure 1, 1 represents the camera body, 2 the lens, 3 the film guide through which the three

films

4, 5, and 6 are caused to travel from the chamber 7 in which the

spools

8, 9, and 10 for the individual films are located, while 11 represents a chamher in which the take-

up spools

12, 13 and 14 are arranged.

Referring to Figures 2 and 3, 15 is a spool of the character usually employed with roll l J 1 i sensitivity cos er llierc- 1S a lever oi lien-sensitive emulsion ti; m

.i sensitivity ve emulsion, (W n 1 r P so e CEllUlOlCZ support ror the some, 21 lever 01 light-sensitive emulsion of blue irom source of light.

Qertsin of the layers of light sensitive con1- position may be arranged to act as cornpen. satiric filters. such films being dyed with nonsensitizing rlyes while the opacity or translucency of the emulsions may be regulated to facilitate securing the desirerl degree of speecl or sensitivity to light of the several ligh sensitive layers.

l Vnen iilnis of celluloicl of suitable thinness are employed as supports for the several emulsions it may lie foundl unnecessary to use stripping films but when stripping films are userl in accordance with the invention they will be of known character insofar as their capacity to lie stripped from their original support is concernml.

arrangement of the several layers of light-sensitive composition in the manner above clelineo encl by the regulation of the sensitivity, opacity and translucency of the several layers, a means for producing negrotive irsges sclaptecl for use in the produc H tion mposite representations in natural be secured which will be capable no at speecls comparable with the R istive telling combination rcolor liy comprising a, roll new -g s plu zri'ble strips of transparent ms 1 super-imposition, a coating on cool; trips 0 ligr'; sensitive materiel sesensitive t lipt rays forming pen sncls of ale spectrum, which strips, iosure eveloprnent, when superorm & complete, negative, composntation of s sulbject in substantitursl colors, and one ofsoicl costsensiiive materiel lacing selec as to blue rays of light sncl lie 'l on the strip of transparent insiclz is farthest from the source of exposure.

liln; for color photography conileg Lnree super-imposes strips of ligl1texposure, each strip bein -'e ecti' el sensi tive to light rays of o p a of the roll for ing exposure lolne rays of 3. roll nine fo color photography comprising three .roposecl strips of lightsensitive meterisls "for sectional. simultaneous exposure, slie strip or the roll positioned forthest from the light source (luring exposure lacing selectively sensitive to blue rays of light, the strip nearest the light source during exposure being selectively sensitive to red rays of light, sncl the intermediate strip oeselectively sensitive to rays of: light. A negative roll film taking: combination for color photography comprising a fiexilolo backing strip, a plurality of flexible strips of transparent material secure thereto scliacent to one encl of each of seicl strips, and in super-imposition, and s.- coating on escli or" said transparent strips of as light sensitive emulsion. each costing being selectively sensitive to light rays forming e particular band of the spectrum, "which strips, after exposure ancl development, when super-imposed, will form :1 complete negative. composite, representetion, of a sulsiect in substantially its natural colors, one of seicl emulsion coated strips losing selectively sensitive to blue rays of light and lieing locatecl immediately ecijecent said backing; strip during; exposure.

5. A roll lilzn for color photography comprising s flexible strip of opseue msterisl, a plurality of strips of flexible. trans -oznreiit materiel reniovsloly securecl at one end to backing strip in superimposition, s, He st-sensitive coating on each of saicl transpsirent strips. each costing being selectively sensitive to light rays forming; a, particular losnfi of the spectrum, which strips, after exposure rlevelopni nt, vvlien superior posed, will form complete res stive. com-4 posits. representation of s sulo iect in snbstentisllv its natnrsl colors, one of ssirl coatecl strips losing selectively sensitive lolue rays of light sini acing" locsterl innneclmtelv :1- cent ssicl'opaque necking strip (luring exposure.

6. A roll film for color photography com prising a fierili e strp of open: lonclrino: rosterei. :1 plursli""" o1 strios of Horrible. transparen materiel ns-evenly secn' erl at one eiui we IilT) in superimposition, it

costing on eecl'i oi' sairl trimsnsrent strip on costing liei g selectively ensitive to m; rays "formi: particular lioncl of the spectrum, WlilCl] st of light and being located inimecliwtely so;