US1892683A - Single plate multiple photographic reproduction - Google Patents

Description

Jan. 3, 1933. R. R. ROBERTSON ,5

SINGLE PLATE MULTIPLE PHOTOGRAPHIC REPRODUCTION File'd June 27, 1.929 6 Sheets-Sheet l @Mif Jan. 3, 1933. R. R. ROBERTSON SINGLE PLATE MULTIPLE PHOTOGRAPHIG REPRODUCTION 6 Sheets-Sheet 5 Filed June 27, 1929 71 foi a ior via 44,;

l i I 1 Qf a 1 Jan. 3, 1933. R. R. ROBERTSON 1,892,683

SINGLE PLATE MULTI PLE PHOTOGRAPHIC REPRODUCTION Filed June 27, 1929 6 Sheets-Sheet 4 Wit? 7501562 6]? jobs/$070- Jan. 3, 1933. R. R. ROBERTSON 1,392,683

SINGLE PLATE MULTIPLE PHOTOGRAPHIC REPRODUCTION Filed June 27, 1929 6 Sheets-Sheet 5 Merl/221 j 0681 121266030);

Jan. 3, 1933. R. R. ROBERTSON SINGLE PLATE MULTIPLE PHOTOGRAPHIC REPRODUCTION 6 Sheets-Sheet 6 Filed June 27. 1929 o o oo o o 00 O0 0 o o o oo oo oo 00 o e 000 00 o 0 0o 0 o o o 0000 00 oo 0 ooooooooooooooooooooooo 0 00 0 0o 00 00 9 a 0 0 0'0 00 o o so 0 o 00 o o o 00 GO 0 o o o o o oo o o oo o 0 oo oo oo o Q00 00 oo 0 o 00 o e o e o o o 0 so 0 o o o o 000 00 o o o o oo o o o o o o 00 0 00 Q o o 00 0G 0 o o o o 0 Www Patented Jan. 3, 1933 UNITED STATES nom'r-a. nomrsox, or nvmsron, rumors anion: 'rm'ra mmrrrmi rnoroemmc aaraonucrron' Applleaflen and June, me. Serial so. 374,250.

' This invention relates to re roduction, by 3 the procem of photography, copy sub ects, "for instance, photographic reproduction practiced as a step in the art'of producing printing forms, and has for its object to economize in time and expense of materials used in.;performin the step which relates particularly to ma ing negatives of a plub rality offcopy subjects of printing forms, it has been necessa to take each copy subject and photograp it upon a special plate which is then handled and treated through the remainin steps of of the process, with the result that e greater portion of the work, being multiplied accordmg to the number of copy subjects handled,

was very expensive in point of time and materials consumed, and very uneconomical in the consumption of the sensitized photographic plate or film that had to be subjected.

to exposure in producing the negative. The resent invention proceeds upon the i5 princip e of photographing a considerable number of copy sub ects all upon one and the same sensitized surface, under conditions which afford the same ran e of independent treatment of the copy sub ect, as to size and intensity of exposure, as if a separate plate were used for each copy subject. Collateral features of the invention have to do with a j method of indicating by previously formed plat or chart, the precise arrangement of ex posures upon the sensitized surface that should be made in order to carry out the 'proc .ess mosteconomically; also with apparatus for accurately locating copy subjects upon a a copy holder in positions corresponding to the i chart, and correspondingly locating the image upon the sensitized surface within the camera; also with means for effecting necessary adjustments of the lens of the camera tqinsure proper projection of the image upon a predetermined limited space of the sensitized surface; also with means for screening, at will, any restricted portion of a sensitized surface with effective screening and protection of the remainder of the surface against light; also with means whereby the several engaging the sheet to be held. Heretofore, In making negatives of copy subjects as a preliminary to the production features of the invention may be adapted to photograph? through means of a aratus aving the coal axis of the lens para el with the surface of the cop holder; and with improved means for hol ing the'copy subject or 'a'sensitized film or sheet upon a supporting surface or any selected portion thereof without the use of means penetrating orotherwise In the accompanying drawings+ 1 v Figure 1 is a side e'levation of a commercial camera of known form in which the several features of my invention'are embodied.

Figure 2 is a front elevation of the same with the copy holder removed. v n

Figure 3 is a section on the line 3w-3a: of Figures 1, 4, and 5.: Y Figure 4 is a sectionyon the line 407-42 of Figures 2, 3,5, and 12.

Figure 5 is a s'ection'on the'line 5:v'-5:v of Figures 3, 4, and 12. a

Figure 6 is a detail view showing one method of holding a copy subject or a sensitized film or sheet to a supporting surface by air suction.

Figure '7 is a section on the line/(M702 of Fi re 8.- n

I igure 8 is a section on the line Bar-8230f Fi re 7. Figure 9 is a front view ofthe copy holder shown in Figure 1. i, p I

Figure 10 is a face'view of the guide chart previously made up to indicate the location of copy subjects in a manner to insure most economical arrangement of their images upon the sensitized surface and as a preliminary to which corresponding placement of the copy subjects upon the copy holder of Figure 9 must be resorted to.

Figurell is a view showin the arrangement of the copying camera wit its focal axis parallel to the plane of the copy holder.

Figure 12 is a view corresponding to Figure 3 showing the means through which to effect adjustment of the lens required in using the arrangement of Figure 11.

Figure 13 is a view illustrating the appli- 'cation of the invention to a darkroom into which an immovable lens projects its beam, with a constantly positioned axis upon a senferre sitized surface supported with universal adjustment in order to bring any desired restricted portion of the surface under the influence of the beam.

Figure 14 is a detail perspective view of the universally adjustable support for the sensitized surface in Figure 13; and

Figure 15 shows a modified construction of means for holding a sheet against a support through means of air suction without mutilation of the sheet.

Referring first to the illustrative embodiment of the invention disclosed in Figures 1 to 10 inclusive, where the invention is shown applied to a copying camera operating with the axis of the lens perpendicular to the plane of the copy'subject, 1 represents a conventional copy holder modified to embody that part of the present invention which has to do with facilitating the location of the copy subject on the holder in correspondence with the position which the image is to occupy in the multiple subject photograph. 2 represents the standard commercial copying camera modified according to the present invention to adapt it to shift its lens and expose limited ortions of its sensitized surface in correspon ence with the required location of each image on the multiple negative to be produced. 3 represents a known construction of carriage upon which the camera is mounted with such movement as is required for determining focal distance, and which carriage is preferably mounted in a known manner through the medium of a bed 4 and shock absorbing suspension means 4a upon trucks 5; a gauge 6 being provided to indicate the position of the carriageB upon the bed 4, which position may receive its fine ad j ustment through means of the hand wheel 7. 8 represents a compensating gauge indicating correfltive carriage positions hereinafter re- 9 indicates, generally, the lens of the camera which, for purposes of that application of the invention illustrated in Figures 1 to 10, is adapted to receive the horizontal movement registered by the scale 9g traversed with the indicator 9h that moves with the lens, and the Vertical movement registered by the scale 9e traversed by index 9} which partakes of the vertical movement of the lens; these movements of the lens being accompanied by shifting of light screens that protect the interior of the camera from the admission of light otherwise than through the lens, for instance, vertically acting light screens consisting of curtains 9a which extend from the top and bottom of the lens frame 9m to spring rollers 96, and horizontally acting curtains 90 wh ch extend from spring rollers 9d to guideways 95 which light-seal the edges of the curtains 90. It is to be noted that the rollers 97) on curtains 9a are mounted on or otherwise arranged to travel laterally with the guides 9a. By this arrangement, the lens 9 may be moved laterally until its frame encounters one or the other of the rollers 9d and while in either of these positions, or any position intermediate thereof, may be moved vertically upon the guides 9i until it encounters one or the other of the curtain rollers 91), or may be stop ed in any position inteJmediate thereof. Index 9f receives movement of the lens 9 through the medium of the cross bar 9k upon which the frame 9a: of lens 9 slides laterally, and the index is thus affected only by the vertical movements of the lens. Index 9h, as shown in Figure 4, is supported between the guides 9i which have only lateral movement, and therefore this index partakes of lateral movements of the lens but is unaffected by vertical movements.

In order to protect the main area of the sensitized surface in the camera while exposing a limited area of any desired dimensions to the beam projected by the lens, I employ the arrangement shown in Figures 7 and 8, wherein 10 represents the focus frame of the camera, 10a represent top and bottom spring curtain rolls therein, and 10b represent laterally disposed spring curtain rolls. From the rolls 10a, curtains 10c extend vertically upward and downward to controlling bn rs 10d to which the free edges of said ourtains are united in a manner to control said edges both as to vertical movement and the plane in which they lie; said rods 10d being extended outwardly through slots 10c in the focus frame 10 to slide bearings 10f arranged for manipulation and vertical movement upon the vertical slide bars 10g. Similarly, curtains 10h extend from the rollers 10b laterally to controlling rods 102' which, like the rods 10d, extend through slots 10]: in the focal frame 10 to slide bearin 10l guided by horizontal slide rods 10m an through which said vertical rods 10i may be manipulated. Spacing of the two pairs of curtains 10c and 10k establishes the confines of an exposure 1 area 11 over the focal plane of the camera;

the pair 100 overlap the pair 10h so that whatever vertical dimension may be given to the exposure space 11 by regulation of the distance between the two rods 10d will leave the lateral confines of the exposure space unchanged; and, similarly, whatever horizontal dimension may be given to the space 11 by changing the distance between the bars 10i will not affect the vertical dimension of said space. Moreover, since the bars 104, with any selected spacing, may be located anywhere within the vertical range of the focal area, and the bars 10:, with any selected spacing, can be moved anywhere within the horizontal dimension of the focal area, the evposure area defined by the four bars can be given any desired rectangular fot'm and located in any part of the area.

escapes With a camera equipped for adjustment of its lens and limitation of exposure area as to dimensions and location, as above described,

it is merely necessary to appropriately I locate the copy subjects on the copy holder 1 relatively large dimensions with independent non-interfering exposures without danger of any of them becoming 1i ght-struck, and thereby roduce an exposed plate or film upon which a l of the exposures can be developed simultaneously, with the expenditure of labor, time, and materials incident to but a single development The. negative thus produced can thereafter be used throughvarious steps of thereproduction rocess incident to the making of printing orms or other industrial processes in a very economical manner. V

In order to facilitate accurate location of the copy subjects upon the copy holder 1, and to do so pursuant to instructions of a skilled director who mayhave before him the entire grist of work to be done within a given period and thus be enabled to prescribe their. best arrangement from an economical viewpoint, the invention provides for theuse of a chart 12 (Figure 10), which is made up of rectangular forms drawn to scale and representative of individual copy subjects selectively grouped upon a sheet representative of the area of the copy holderas well as the area of the sensitized surface within the camera; and these prescribed figures, bearing suitable index characters, forinstance, A, B,

-C, D, etc. which are likewise borne upon the copy subject, and preferably alsobeing marked with the dimensions of the reproduction image to be projected onto the sensitized surface, are read off as to the position to be selected for their counterparts on the copy holder by reference to marginalfigures extendingin two rectangular directions. And to facilitate establishing the loci of the copy subjects on the. copv holder 1, the copy holder is provided with range bars 13, 14 mounted through means of slide bearings 15,16 upon a pair of vertical bars 17 and a single horizontal bar 18. so thatif from among the copy subjects furnished to the cameraman, a subject marked A is selected', the cameraman looks at the chart 12 (Figure 10) and finds that this copy subject is to be'located on the, copy holder with its center defined by, the vertical line 2and a horizontal line intermediate of the horizon-.

copy holder 1, andthehorizontal bar 13 until it lies between the figures 2 and 3 of the vertical series of figures on the copy holder 1;

and he attaches the copy subject A to the copy holder 1 with the geometrical center of the copy subject behind the intersection of the bars 13 and 14, and, after returning the range bars to unobstructed position, proceeds to make the exposure in the camera. But before making the exposure, the cameraman adjusts the lens 90f the camera until the indexes 9k and 9f point to corresponding figures to insure projection to the proper limited exposure area on the sensitized surface, and adjusts the slide bearings 10f, 101 (Figure?) until they, respectively, reach'positions defined by their ointers-lOfw, 101m in conjunction with gra uations 10fy, 10Z 1 on the back of the camera, as shown in dotted lines corresponding with marginal readings of the rectangle representing the selected copy'subject on the chart 12; whereupon, the proper .distance adjustment of the lens 9 from the copy holder 1 having been made appropriate to the size indicatedon the rectangle A (or on the copy subject-if preferred), and the focal adjustment appropriate to said distance having been made with the focal plane ofthe camera, the exposure of the particularf'icopy subject is completed and another copy sub- 1,

ject .is selected and theoperation repeated. This continues until selectively defined, reduced exposure areas aggregating substantially the whole sensitized area have been used up, whereupon the plate or film will be removed and allof the-exposures are treated collectively in the ensuing development," as well as in other steps in the industrialprocess for which the exposures were made, for instance, in the process-of producing printing forms, the steps which consists in light-printing from the multiple subject photograph negative upon a surface to be etched, then etching said surface and otherwise finlshing the printing form before cutting up the etched plate into individualhalftones or the like. Thus,.theprocedure is carried out with economy commensurate with the use of a single manipulation for each step (in the present invention) vas compared with as many manipulations astherewere copy subjects (in the old method of procedure). i

As a convenient method of causing paper copy subjects to adhere to any selected posi-* tion 'on the copy-holder without mutilation incident to the usual mechanical means for attaching the paper, Figure 6 represents a copy holder consistingofa board 19 having perforations 20 and backed by an exhaust chamber21connected through suction hose 22 with a'fan 23 driven by electric motor 24; suct on hose 22 and fan 23 being connected by flexible connection 22a to. eliminate vibras tion,v r By permitting the motor 24 to run constantly during the use of the copy holderand having the suction capacity of the fan 23 materially in excess of the total capacity of the perforations 20, sufiicient suction will boar 19 while it is exist at all :times 'through'anyygrou'p of 1 per forationsQO to draw -a paper 'copyxaub ect *firml and smoothl to the surface of the ing hoto bed.

If the invention is to em ied in a camera mounted with the axis of its lens rallel with the 'plane of the copy holder or instance, as illustratedin Figures Hand '12 wherein light is received from the cop subject on the cop holder 1a through .a reflecting prism 25, t e lens 9 (Figure "12) will have itsframe 9o: sliding'vertically elgwonthe curtain bars 91' to positions registe by the as-already described with reference "to Figure 2, and similarly will'have its curtainbars 91' sliding horizontall to give the lens a position registered by t e index 91;. In other words, lens adjustment and construction permit ingthe same .may be substantially asin the cm of the invention describedinvFigures 1 to 10, as also may be the curtain adjustments over the sensitized surfacein the focus framelO. But the adjustment ofthe camera relativelyto the copy holder 10 will be horizontal travel-of the'lens 9, while deter- :min' the position of del1very.of.its.beam :upoii fiie sensitized surface, doesnot-ehanfie horizontallyin itsrelationrto the copy-ho er; it mere vafiects focal distance, whichIis neutralized y correspond ad ustment of the camera as a whole thro the medium of its carriage 3a'upon'the 4a (Figure 11) through a corrective distance1 d f the com nsati 1 8,-t erea ings c .which w illypref e a l y fi in :figunes identical with the laterally extending-'position-indicatthe chart 12 (Figure "10).

res on the chart .12 (Figure m). ore, all copy subjects-placed uponthe holder 10 will be on the vertical line 1Y0! some other line ina-verticalplane centralto the reflector and perpendicular to the holdf -er1a,.and only vertical variations aretaken into accountin'positio copy subjects on the holder 1a, namely,-variations co d ing to vertical adjustments of the lens "9 rthe'vertical distance from top or'bottom of the vrestrictedexpcsuze areatselected within the camera. Thus, .to use the camera disclosed in Figures'll and '12, a copywsubject will be placed upon'theholder'la with its center approximately in ttheivertical c line Y and behind the vertically'adjustable'cmm bar 18a when the latter is occup a position in relation'to the vertical seri offiguresz called for by the vertical marginal figures in marginal-figures in the chart '12 :(Figure 10) would be taken into account in; selecting :the

position of the indicatorrtlhlinFigure 12, but v 'notin determining the I location of the copy subject onithe holder :10 (Figure 511) ,because in 'thisarmngement of the camera, the lens dcesnotxmovexin thedirection of its axis (undifl'erentfor the reason that to '16 through the medium of restricted areas of the Figure 13, manually placed overlapping curtains or Fleas it be as a convenientway of c subject) operating with copy subjects outside of the dark the thro h room and bringing the ima (and pre erably t 0 medium of the lens y prismatic reflector) through a wlpll (for ind e dar room an stance, the top wall) of t projecting it upon a sensitized surface supported upon a table conveniently located for observation and manipulation of the actinized film or late, as well as protecting curtains manipu ated to selectively limit exposure areas as taught by the present invention.

In Figure 13, It represents the cop holder, 25a re resents a reflecting prism, an 9 a lens loca to receive light reflected from the copy holder 1b and ro'ect the image through the top wall 26 ofthe dark room 27 toa horizontal focal table 28,

upon which may placed a sensitized film or plate to be exposed holder 16. In this arrangement, lens 9, with its reflector 25, is preferably stationary on thetop wall 26 of the dark room 27 ;distance between-the lens and the copy holder which determines the size of re latedby movably mounting the copy he or ca 29 equipped with a known type "of distance gahgge "30; and focal adjustments are accomp ed by movement of the focus table 28 verticallythrough the medium of @118! justa mount' be" ui with such other aaeeaorie ia fis $1? dzs ig ble or convenient, such for instance, as hand wheel 33 e mion 31, a bracket wheel 84 or table at any adjustment, and colmterbalance for facilitating the the table. With an arrangement of from Figure 14, any desired subdivision of the surface of the table 28 may be resented in line with the focal axis of the ens 9 by moving the base 36 on the sub-base 37 in one directiomfor instance, from righ Figure 13 and .the'table28 upon the base 36 the v r direction, for instance, from front to rear as viewed in Figure 13. In thus us' the feature of the wli ilfii hasto do with successively ex ing sensitized sur ace in for turning light-intercepting boards or the like Ina be em loyed; or the arrangement shown could be bodily substituted for 28.

It is to be understood that the device shown be applied to the manner of a sepaor film holder, as,

in 7 and 8 is to camera much after the rately constructed plate of copy subjects mounted upon the production, is

inion 81 with rack 82; such vertically add, as may be readily seen ttoleftin present invention for instance, by placing it in rear of the camera shown in Figure 1, or the camera shown in Figure 11, or otherwise combining it with a camera having the laterally an vertically adjustable lens herein disclosed.

An alternative method of causing cop subjects or, if desired, sensitized film, to a here to the plane surface of a holder without the use of mechanical attachments, is illustrated in Figure 15, in which the perforated screen 19a is subject to the vacuum effect of a fan 23a so located in relation to the opposite side of the screen from the sheet to be held as to develop a partial vacuum sufficient to hold. the sheet in place by suction.

The means shown in Figure 15 for holding a sheet or film is preferable to that shown in Fi ure 6, for the reason that, While in Fi re 6 the portion 220; of the air conduit is ru her and largely avoids transmission of vibration from the motor to the holder, there is in Figure 15 a total absence of mechanical or vibration-transmitting connection between the fan and the holder.

It is to be understood that in the cameras herein shown any desired 1i ht-controlling cap maybe employed, such, or instance, as caps or shutters for the lens, as well as adjustable diaphragms, timing mechanism, and the like. These have not been disclosed because they form no part of the present invention. I

I claim:

The improvement in the art of photographically exposing difierent portions of a single sensitized surface to a corresponding number of separate copy subjects, which consists in preparing a master chart having designated positions corresponding to the respective copy subjects, then mounting the copy subjects upon a copy board having designations capable of defining ositions corresponding to the positions esi ated upon the chart, then manipulating the lens of a 1 camera into a plurality of positions designated similarly to the positions of the copy subjects on the copy board and from which the lens projects images upon portions of the sensitized surface corresponding to the chart, and successively exposin J the lens in the respective positions to whic it is adjusted while masking the portions of the sensitized surface other than that upon which the image is to be projected.

Signed at Ghicagmlllinois, this 15th day of June, 1929,

ROBERT R. ROBERTSON.

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