US2315101A

US2315101A - Dropout half-tone negative

Info

Publication number: US2315101A
Application number: US404572A
Authority: US
Inventors: Zukmann Laszlo
Original assignee: Individual
Current assignee: Individual
Priority date: 1941-07-29
Filing date: 1941-07-29
Publication date: 1943-03-30
Anticipated expiration: 1960-03-30
Also published as: CH245394A

Description

March 30, 1943. ZUKMANN 2,315,101

DROP-OUT HALF-TONE NEGATIVE Filed July 29, 1941 3 Sheets-Sheet l INVENTOR [0.5210 Zak/22mm March 30; 1943.

L. ZUKMANN 2,315,101 DROP-OUT HALF-TONE NEGATIVE Filed July 29, 1941 3 Sheets-Sheet 2 INVENTOR t Qaszlo Zak/220121;

March 30, 1943. ZUKMANN DROP-OUT HALF-TONE NEGATIVE Filed July 29, 1941 3 Sheets-Sheet 3 INVENTOR. lasz/a Z zl/i ma/m Patented Mar. 30, 1943 UNITED STATES PATENT OFFICE- 2,315,101 nnorou'r HALF-TONE NEGATIVE Laszlo Zukmann, New York, N. Y. Application July 29, 1941, Serial No. 404,572

. 24 Claims.- (01. 95-5) This invention relates to a' new and improved process of preparing printing plates and more particularly to a process of eliminating all screening or dots in the background or high-light sections of a half-tone positive or negative. This process is particularly adaptable for the type of photoengraving and illustration commonly used for newspaper advertising.

An object of this invention is to provide a simple process of high-lighting which is tree from the prevailing, lengthy, and inexpedient methods.

Another object of this invention is to provide a process which will greatly diminish the necessity of using skilled labor and which will facilitate the production of printing plates.

Briefly, the proposed new process comprises the following steps:

First, from an original drawing having highlight and tone sections is prepared a negative, having substantially transparent portions corresponding to the tone sections, and substantially opaque portions corresponding to the high-light sections of the original drawing. In the following description such a negative will be called half tone mask negative. has also line sections which should be reproduced as opaque continuous lines, first a negative is prepared which; has transparent portions corresponding to the tone and line sections, and opaque portions corresponding to the high-light sections of the original drawing. In the following, such a negative will be called a "half tone and line mask negative.

Thereafter is prepared a positive having substantially opaque portions corresponding to the tone sections, and substantially transparent portions corresponding to the high-light sections of the original drawing. In the following description such a positive will be called a half tone mask positive. If the original drawing contains also line sections which should be reproduced as opaque continuous lines, the mask positive will also have opaque portions corresponding to these line sections; in the following such a positive will be called a. half tone and line mask positive.

In case the original drawing contains only high ight and tone sections, the next step -will consist in photographing the original drawing on a light-sensitive photographic material successively through the above defined half-tone mask negative and half-tone mask positive in such a manner that a half-tone screen is interposed between the drawing and the light-sensitive material when the drawing is photographed through thehalf-tone mask negative. In case the original If the original drawing.

drawing contains also live sections, the original drawing may be photographed through a halftone and line mask positive instead of the half-,- tone mask positive mentioned above.

This new process results in a drop-out halftone negative having opaque portions correspond ing to the high-light sections, and half-tone portions corresponding to the tone sections of the original drawing. In case the original contains also lines, i. e. is a combination of tone, line, and high-light sections, the new process results in a drop-out halt tone and line negative having opaque portions corresponding to the high-light sections, 'hal-f tone portions corresponding to the tone sections,

I and transparent portions corresponding to the line sections of the original drawing.

It should :be noted that throughout this application the term, high-light" is used to desigmate the sections of an illustration or drawing which are required to be printed in reproduction as pure \white, orasfree from screen pattern, and

is usually considered as referring to background or white? sections of an illustration. The term, "tone sections refers to the shaded or dark parts of an illustration. The term, line sections" refers to the continuous opaque lines appearing on an illustration. These terms are also to indicate areas on a negative which correspond to the designated sections in the original illustration.

Furthermore, it should be noted that the term, "negative" is used throughout thespeciflcation to designate photographic reproductions on whatever type of photographic material in which the high-light sections of the illustration appear opaque and the tone sections appear more or less transparent. In'the same way, the term, positive designates photographic reproduction on whatever kind of photographic aterial, i. e., on

paper, film, or photographic pla e, in which the this white background has to be reproduced without screening.

The novel features which I consider as characteristic for my invention are set forth in particular in theappended claims. The invention itseli', however, both as to its construction and.

its method of operation. together with additional objects andladvantages thereof will be best understood from, the Iollowing description oi. specific embodiments, when'read in connection with the accompanying drawings, in which:

Fig. 1 illustrates a type of drawing having tone and high-light sections where, in. printed reproduction, elimination of half tones is required-inthe high-light sections. i. e. in the sections shown in thi figure in pure'white; I h h Fig. 2 represents a continuous tone negative made fromthedrawingshown inFig. 1; 1

Fig. 3 shows a halt .tone mask negative 'made' out half tone negative from the original shown in Fig.

A Fig. 8 is a drop-out half-tone negative made in accordance with the present invention;

Fig-.9 illustrates a type of drawing having tone,

line; and high-light sections;

Fig. represents a continuous tone negative made from the drawing shown in Fig. 9:

. and? are expanded views oi photo j graphic arrangements used for making'a drop- ';high-light sections 2|.and transparent portions 28 corresponding to the tone sections 22 of the positive shown'in Fig. 4, is superimposed onthex graphic step results in exposure of all the por-" I tions of the light-sensitive surface of photographoriginal drawing.

Third steps-From this half tone masknega tive 2-i't'he half-tone mask positive 28, shown in Fig. 4 is made, by printing the same on a photographic material consisting of a transparent basepro'vided'with a light-sensitive layer. After exposure, the print. is treated in the usualway undresults in' ahali-tone mask positive having transparent portions 29 corresponding to the high-light sections 2|, and opaque portions 30 corresponding to Fourth step-Thereafter, the half tonezrnask original drawing in, the way shown in Fig. 6, and

the original drawing 20 photographed through; the half tonemask positive 28 onto the lightsensitive photographic material 3|. This photoic material 3i corresponding t the high-light sections 2| of-the original drawing which are covered onhr' bythe' transparent-portions 29 of'th'e 1 halt tone mask positive, 28 superimposed on the drawing 20; those portions of the light-sensitive "surface 01 photographic material 3| which corre- Fig. 111- represents a half tone and line mask' negative made from the;cont inuou tonenega:

tive shown in Fig. 10;

Fig. 12 shows a half tive printed'irom the half tone and line masknegative shown in Fig. 11; j

Fig.'13shows a half tone masknegative produced by retouching the half tone and line mask negative shown in Fig. 11; I

Fig. 14 shows a halt tone mask positive produced by printing the half tone mask negative shown in Fig. i3; and

Figs. 15, 16, and 17 are expanded views of photographic arrangements used for making a dropout half tone and line negative from the original shown in Fig. 9; and I Fig. 18 is a drop-out half-tone and line negative made in accordance with the present invenion.

t The process of producing a drop-out half tone negative from the original drawing 20 having, as shown in Fig. 1, high-light sections 2| and tone sections 22, comprises in accordance with one embodiment of the present invention the following steps:

in Fig. 1, the continuous tone negative 2I shown in Fig. 2 is made. This continuous tone negative.

has opaque portions 22 corresponding to the highlight siection's', and negative tonepo'rtions 2i correspondingto the positive tone sections 22 of the originaldrawing 28. This continuous tone negative ismade in the usual way.

Second step-From this continuous tone negative the half tone mask negative shown in Fig. 3 is made by treating the continuous tone negative, shown in Fig. 2. while still wet with a photographic reducer until the tones oi the tone portions disappear; thereafter, the I thus produced half tone mask negative is fixed. washed, and finally dried. This results in the half tone mask negative shown in Fig. 3; this mask negative has opaque portions 21* correspond g to the tone line mask posispond to the tone sections 22 of the original drawing'and are covered by the opaque portions 30 of the half tone positive, remain unexposed.

Fifth. step-Thereafter, the half tone mask positive 28 is removed and replaced by the half tone mask negative 26; it must be stressed that this change must be carried out without altering the relative position of the original drawing-20 w and the partly exposed light-sensitive photographic material 3|.' The halftone screen 32 i consistingot opaque screening lines 33 on a transparent base 34 is placedbetween the half graphic material 3|. As those surface portions of the photographic material 3| which correspond to the tone sections 22 are still unexposed, this exposure results in a screened, i. e. half tone negative image of the positive tone sections 22 of the original drawing on these unexposed por- 1 tions of the photographic material 3|.

Sixth step.The photographic negative ma- .terial is then developed, fixed, washed, and dried.

as usual in making negatives. This treatment results in the drop-out half tone negative 32' shown in Fig. 8; this drop-out half tone negative has, in accordance with the present invention, opaque portions 38' corresponding to the highand line negatives.

light sections 2|, and half tone, i. e'.; screened negative tone portions 34' corresponding to the positive tone sections 22 01' the original drawing 20.

As stated above, the present process is particularly adapted for producing drop-out half tone Such negatives are to be made from drawings of the type shown in Fig. 9; such drawings 35 have high-light section 38, tone sections 21 and line sections 38. The process of producing from such a drawing a drop-out and half tone line negative comprises, in accordance with one preferred embodiment of the present invention the following steps:

Step one-From theoriginal drawing shown in Fig. 9, the continuous tone negative 39 is made h tonesections 22 of the'ori'g. 1 a ing-22. i

aerator in the usual way. As shown in Fig. 10, this continuous tone negative "has; opaque portions 40 corresponding to the ,high-light sections .36, transparent portions 4| corresponding to the line sections 38, and negative tone sections 4'! terial u is then developed. fixed. when, aid

corresponding to the positive. tone sections 31 of 3 the original drawing 35. I

Step two..-From. this continuoustone negative 3! is made the half tone and line mask negative 43, shown in Fig. 11, in the way described above.

This mask negative 43 hasv opaqueportions 44 corresponding to.the high-light sections, and

transparent portions

45 and 45 corresponding to the line sections 38 and tone sections 31, respectively, of .the original drawing.

Step three..From this half tone and line mask negative 43, shown in Fig. 11, the half tone and line mask positive 41, shown in Fig. 12,.is made by photographic printing. This half tone and line mask .positive 41 hastransparentportions 48 corresponding to the high-light sections 36,

and opaque. portions 43 and corresponding to the line sections and tone sections 31, respectively, of the, original drawing35. I

Step four.-Thereafter, the half tone and line mask negative 43, shown in Fig. 11, is transformed by opaquing the transparent line portions 54 into the half tone mask negative 5|, shown in Fig. 13. This mask negative 5| has

opaque portions

52 and 53 corresponding to the high-light sections 35, and line sections 38, respectively, and has transparent portions 54 corresponding to the tone sec.- tions 31 of the original drawing 35.

Step five.-Having thus made the half tone and line mask positive 41 and the half tone mask.

negative 5|, and having at disposal also the half tone screen 32 shown in Fig. 5, the original drawing is photographed indifferent combinations with these masks and the screen: As shown in Fig. 15, thehalf tone and line mask positive 41 is superimposed on the original drawing 35 and the drawing is photographed through this mask on the light-sensitive photographic material 55 consisting of a light-sensitive emulsion on a transparent base. After exposure, the mask 41 is removed without altering the relative posi- .tone portions 53 corresponding dried as usualin making negatives. -This treat ment results in' the drop-outhalf tone and line negative 55, shown in Fig. 18; this drop-out half tone and line'negative h as', in accordance with the present invention, opaque portions 51 corresponding to the high-light section 35, transparent: portions 55 corresponding to the line sections 38, and half tone, ire. screened negative to the tone sec tions 31 of the original drawing.

Step-eight.-As well known in making half tone screen negatives, it is expedient to perform another operation which is universally used and is called, flashing. Without this'fla'shing there would be no screening in the darker parts of the halfv tone portionsof the negative because the corresponding sections of the original drawing reflect little or no light. 'The" purposeof the flashing is to create this screening in the darker half tone portion of the negative." If this flashing operation were performed in the usual way, the screening would appear not only in the half tone portions but also in the line portions of the negative; the continuity and transparency of these line portions would thereby be broken up and the object of the present invention defeated.

tion of the drawing 35 and the photographic material 55.

Step sin-Thereafter, the half tone mask neeative 5| is superimposed on the original drawing 35 and the half tone screen 32 is interposed between this half tone negative 5| and the lightsensitive photographic material 55. (See Fig. 16.) In view of the fact that during photographing the drawing through the half tone and line mask positive 41 in the way described above, the lightsensitive layer of the photographic negative material 55 will have been exposedonly by the highlight sections of the ori inal drawin those portions of the li ht-sensitive layer which correspond to the line and

tone portions

49 and 50 of the mask positive 41 remain unexposed. Now, when photographing the drawing through the half tone mask negative 5| only those portionsof the negative material which correspond to the tone portions 54 of the mask ne ative 5| will be exposed. while all other portions. particularly the unexposed line portions remain unexposed. As the tone sections 31' of the ori nal drawing are photographed through screen 32 and the transparent tone portions 54 of the mask negative 5|, they will finally appear onthe negative photographic material 55 as half tone, 1. e. screened tone portions. u

Step seven The negative photographic ma This difiiculty is overcome by flashing through the half tone mask negative 5|, as-shown in Fig. 17. In performing the flashing'op'eration, a sheet of white paper 50* is "placed immediately behind mask 5| replacing the originaldrawing 35, orarranged between this drawing and'the mask. Since on the half tone mask negative 5| all portions corresponding to the line sections 38 have been retouched, i; e. painted out,"an'd since all portions corresponding to the high-lightse'c tions 36 are. opaque, the portions of'the negative corresponding to these high-light and line'sec tions remain, also after flashing, free --from screening, but the half tone portions appear also in the darker parts with screening.

From the drop-out half tone and line negative produced in the above described way, the next stages of the usual'process can be carried out either by operating directly on the zinc plate or by making a positive, whichever happens to be more convenient. a 3

Although the above described embodiments are the preferred ones, modifications of the new process within the limits of thepre'sent invention are possible. Such modifications are, for instance, the following? It is possible to reverse the i. e.',

photographic. steps. to photograph the original drawing first through the mask negative and the screen, and then through the mask positive. This reversed process has the same result as the above described processes: I

Furthermore. in the process of making a dropout half tone and line negative, it is possible to use a half tone mask positive of the type shown in Fig. 14 instead of the half tone and line mask positive 41" shown in Fig. 12. This half tone mask positive could be used for the-process step shown in Fi 15 with the same result, 1. e. without altering thepicture produced by this step on the light-sensitive photographic material 55.

This is caused by the fact that theline sections 38of the original drawing 35 are also opaque I and, therefore. it'is unnecessary to superimpose upon these opaque line sections 35 of the ori inal drawing the opaque portions '43 of the.

hali'tone and line maskpositive 41.

Furthermore, it is also possible to prevent the I flashing o! the unexposed line portions on the final negative by another method than the one described above This other method consists in using for the process step shown in Fig. 16 the half tone and line mask negative 43 shown in Fig. 11 instead of the retouched hali' tone mask negative 5i shown in Fig. 18. This mask negative 43, however, is not superimposed on the 7 original drawing in register with the same, but

What is claimed as invention and desired to.

be secured by Letters Patent oi the United States is: v

l. In a process of producing a drop-out halt tone negative from an original drawing comprising highlight and tone sections, the steps of making a halt tone mask negative having substantially transparent portions corresponding to the tone sections and substantially op ue portions corresponding to the highlight sections of the original drawing, making a hail tone mask positive comprising substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight sections of the original drawing, and photographing said original drawing on a lightsensitive photographic material successively through each of said masks with, a half tone screen interposed between the drawing and the light-sensitive material when the drawing is photographed through the hall. tone mask negative.

2. In a process of producing a drop-out half tone negative from an original drawing comprising highlight and tone sections, the steps of making a halt tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight sections of the original drawing, making a half tone mask positive comprising substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight sections or the original drawin superimposing said masks one after another unto said original drawing, and photographing said drawing on-a light-sensitive photographic material through each of said superimposed masks with a half tone screen interposed between said drawing. and said light-sensitive material when the drawing is photographed through the half tone mask negative.

3. In a process of producing a drop-out half tone and line negative from an original drawing having highlight, line and tone sections, the steps of making a half tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections of the original drawing, making a hall tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight and line sections of the original drawing, and photographing the original drawing on a light-sensitive photographic material successively through each of said mask; with a hali' tone screen interposed between the drawing and the light-sensitive material when the drawg negative.

ing is photographed through the half tone mask 4. In a process oi producing a drop-out tone and line negative from an original drawin having highlight, line and tone sections, the

one after another unto said original drawing,

and photographing said drawing on a light-sensitlve photographic material through each of said superimposed masks with a half tone screen interposed between said drawing and said lightsensitive material when the drawing is photo-' graphed through the half tone mask negative.

5. In a process 01' producing a drop-out half tone and line negative from an original drawing having highlight, line and tone sections, the

steps of making a half-tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections of the original drawing, making a halt tone and line mask positive having substantially opaque portions corresponding to the tone and line sections and substantially transparent portions corresponding to the highlight sections oi the original drawing, superimposing said masks one after another unto said original drawing, and photographing said drawing on a light-sensitive photographic material through each oi. said superimposed masks with a half tone screen interposed between said drawing and said light-sensitive material when the drawing is photographed through the half tone mask negative.

6. In a process 0! producing a drop-out halt tone negative from an original drawing having highlight and tone sections, the steps of making a halt tone mask negative having substantially transparent portions corresponding to,the tone sections and substantially opaque portions corresponding to the highlight sections oi! the original drawing, making a half tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight sections of the original drawing, photographing the original drawing on a light-sensitive photographic material first through said half tone mask positive, and then photographing said original drawing again on the same light-sensitive material through said half tone mask ngative and a hall tone screen interposed between said mask and the light-sensitive photographic material.

'1. In a process of producing a drop-out half tone negative from an original drawing having highlight and tone sections, the steps of making a halt tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight sections of the original drawing, making a halt tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight sections of the original drawing, superimposing said halt tone mask positive on said original drawing,

photographing the same throughsaid superimposed mask positive on a light-sensitive photographic material, removing said mask positive, superimposing on said drawing said hall tone mask negative, interposing between said superimposed mask negative and said light-sensitive photographic material a half tone screen and photographing said drawing through said mask negative and said half tone screen on the lightsensitive material without altering the relative position of the drawing and the light-sensitive material. A

8. In a process of producing a drop-out half tone and line negative from an original drawing, having highlight, line and tone sections, the steps of making a half tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections of the original drawing, making a hall tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight and line sections of the original drawing, photographing thereafter the original drawing on a light-sensitive photographic mate rialfirst through said half-tone mask positive, and then photographing said original drawing again on the same light-sensitive material through said half tone mask negative, and a halt tone screen interposed between said mask and the light-sensitive photographic material.

9. In'a process of producing a drop-out half tone and 'line negative from an original having highlight, line, and tone sections, the steps of making a hall tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding tothe'highlight and line sections oithe original drawing, making a half tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight and line sections of the original drawing, superimposing said half tone mask positive on said original drawing, photographing the same through said superimposed mask positive on a light-sensitive photographic material, removing said mask positive, superimposing on said drawing aid half tone mask negative, interposing between said superimposed mask negative and said light-sensitive photographic material-a hali' tone screen, and photographing said drawing through said mask negative and said halt tone screen on the lightsensitive material without altering the relative position of the drawing and the light-sensitive material.

10. In a process of tone and line negative from having highlight, line and tone sections, the steps of making a halt tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections of the original drawing, making a halt tone and line mask positive having substantially opaque portions corresponding to the tone and line sections and substantially transparent portions corresponding to the highlight sections of the original drawing, photographing the original drawing on a light-sensiproducing a drop-out half an original drawing drawin material.

tive photographic material that through said halt tone and line mask positive, and then ph graphing said original drawing {again on the same light-sensitive material through said half tone mask negative and a halt tone screen interposed between said mask negative and the lightsensitive photographic material.

11. In a process oi producing a drop-out half tone and line negative from an original drawing having highlight, line and tone sections, the steps of making halt tone masknegative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections of the original drawing, making a halt tone and line mask positive having substantially opaque portions corresponding to the tone and line sections and substantially transparent portions corresponding to the highlight sections of the original drawing, superimposing said halt tone and line mask positive on said original drawing, photographing the same through said superimposed mask positive on a light-sensitive photographic material, removing said mask positive, superimposing on said drawing said half tone mask negative, interposing between said superimposed mask negative and said light-sensitive photographic material a hall tone screen, and photographing said drawing through said mask negative and said half tone screen on sensitive material without altering the relative position of the drawing and the light-sensitive 12. In a process of producing a drop-out half tonenegative from an original drawing,- having highlight and tone sections, the steps of photographically making a halt tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the :highlight sections of the original tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight sections of the original drawing by preparing a photographic print of said half tone mask negative, superimposing said masks one after another unto said original drawing, and photographing sensitive photographic material through each 01 said superimposed masks separately in such a manner that a half tone screen is interposed between said drawing and said light-sensitive material when the drawing is photographed through the hall tone mask negative.

13. In a process of producing a drop-out halt tone and line negative from an original drawing having highlight, line and tone sections, the steps of photographically making a half tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections of the original drawing, making a halt tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight and line sections of the original drawing by preparing a photographic print of said half tone mask negative, and photographing said original drawing on a light-sensitive photographic material successively through each of said masks with a half tone screen interposed between the drawing and the-light-sensitive material when the drawthe light- 7 drawing, making a halt said drawing on a lightdrawing, making a hall tone and line mask positive having substantially opaque portions correspondingto the tone and line sections and subs ntially transparent portions corresponding to the highlight sections of the original drawing by preparing a photographic print of said halt tone and line mask negative, making from said ball tone and line mask negative by opaquing the transparent line portions of said negative a halt tone mask negative, superimposing said halt tone mask negative and said halt tone and line mask positive onto said original drawing in either succession, and photographing said drawing on a light-sensitive photographic material through each of said superimposedmasks separately in such a manner that a halt tone screen is interposed between said drawing and said light-sensitive material when the drawing is photographed through the half tone mask negative.

15. In a process of producing a drop-out halt tone and line negative from an original drawing tone and line mask negative by opaquing the transparent line portions or said negative, a half tone mask negative, superimposing said halt tone and line-mask positive on said original drawing,

' photographing the same through said superimposed,mask positive on a light-sensitive photo-' graphic material, removing said mask positive, superimposing on said drawing said halt tone mask negative. interposing between said superimposed drawing-mask negative assembly and said light-sensitive photographic material a halt tone screen, and photographing said drawing through said mask negative and said hall" tone screen on the light-sensitive material without altering the relative position oi the drawing and the light-sensitive material during the successive photographing or said drawing on said lightsensitive material through said masks.

17. In a process of producing a drop-out hali tone and line negative from an original drawin having highlight, line, and tone sections, the v steps oi photographicaily making a halt tone and having highlight, line, and tone sections, the steps 1 oi photographically making a halt tone and line line mask negative having substantially transparent portions corresponding to the tone and line sections and substantially opaque portions corresponding to the highlight sections or the original drawing, making from said halt tone and line mask negative by opaquing the transparent line portions of said negative a halt tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections of the original drawmask negative having substantially transparent portions corresponding to the tone and line sections and substantially opaque portionscorresponding to the highlight sections of the original drawing. making from said half tone and line mask negative byopaquing the transparent line portions of said negative a halt tone mask negative having substantially transparent portions corresponding to the tone sections and substan- I tially opaque portions corresponding to the highlight and line sections of the original drawing;

making from said hali tone mask negative a halt tone mask positive having substantially opaque portions corresponding to the tone sections and ing, making from said halt tone mask negative a hall. tone mask positive having substantially opaque portions corresponding to' the tone sections and substantially transparent portions corresponding to the highlight sections of the original drawing by preparing a photographic print of said hali' tone mask negative, superimposing said halt tone mask positive on said orginal drawing, photographing the same through said superimposed mask positive on a light-sensitive photographic material, removing said mask positive, superimposing on said drawing said half tone mask negative, interposing between said superimposed drawing-mask negative assembly and said substantially transparent portions corresponding to the highlight and line sections or the original drawing by preparing a photographic print of said hall tone mask negative, superimposing said halt tone mask negative and said halt tone mask positive onto said drawing in either succession, and

photograp g said drawing on alight-sensitive photographic material through .each or said superimposed masks separately in such a manner that a halt tone screen is interposed between said drawing and said light-sensitive materialvwhen the drawing is photographed through the half tone mask negative.

16. In a process of producing a drop-out hall'- light-sensitive photographic material a halt tone screen, and photographing said drawing through said mask negative and said halt tone screen on the light-sensitive material without altering the I relative position of the drawing and the light- H sensitive material during the successive photographing of said drawing on said light-sensitive material through said masks.

18. In a process of producing a drop-out half ton negative from an original drawing having highlight and tone sections, the. steps of makin from, said drawing a continuous tone negative on tone and line negative from an original drawin 1 having highlight, line, and tone sections. thesteps of photographically making a halt tone and line mask negative having substantially transparent portions corresponding to the tone and line sections and substantially opaque portions corresponding to the drawing, making a halt tone and line mask positive having substantially opaque portions cor.- responding to the tone and line sections andsubstantially transparent portions. correspon n to highlight sections of the original I a photographicmaterial consisting of a lightsensitive layer on a transparent base, treating said continuous tone negative while still wet with a photographicreducer until the tones of the tone sections disappear, fixing, washing, and finally drying the thus produced half tone mask negative having substantially transparent portions corresponding to the tone sections and sub 'stantially opaque portions corresponding to the highlight sections of the original drawing, makthe highlight sections 0! the original drawingby preparing a photographic print or said halt tone ing a half tone mask positive having substantially opaque portions corresponding to the tone sec-.

tions and substantiallytransparent portions corresponding to the highlight sections of the original drawing by preparing a photographic print and line mask negative, making from said halt 7g of said'hali tone mask negative, superimposing said masks one after another onto said original drawing, and photographing said drawing on a light-sensitive photographic material through each or said superimposed masks separately in such a manner that a half tone screen is interposed between said drawing and said light-sensitive material when the drawing is photographed through the half tone mask negative.

19. In a process of producing a drop-out hall tone and line negative from an original drawing having highlight, line, and tone sections, the steps of making from said drawing a continuous tone negative on a photographic material consisting of a light-sensitive layer on a transparent base, treating said continuous tone negative while still wet with a photographic reducer until the tones of the tone sections disappear, fixing, washing, and finally drying the thus produced hali' tone and line mask negative having substantially transparent portions corresponding to the tone and line sections and substantially opaque portions corresponding to the highlight sections of the original drawing, making a half tone and line mask positive having substantially opaque portions corresponding to the tone and line sections and substantially transparent portions corresponding to the highlight sections of the original drawing by preparing a print of said half tone and line mask negative, making from said half tone and line mask negative by opaquing the transparent line portions of said negative a half tone mask negative, superimposing said ball tone mask negative and said half tone and line mask positive onto said original drawing in either succession, and photographing said drawing on a light-sensitive photographic material through each of said superimposed masks separately in such a manner that a half tone screen is interposed between said drawing and said light-sensitive material when the drawing is photographed through the half tone mask negative.

20. In a process "of producing a drop-out half tone and line negative from an original drawing having highlight, line, and tone sections, the steps of making from said drawing a continuous tone negative on a photographic material consisting of a light-sensitive layer on a transparent base, treating said continuous tone negative while still wet with a photographic reducer until the tones of the tone sections disappear, fixing, washing, and finally drying the thus produced halt tone and line mask negative having substantially transparent portions corresponding to the tone and line sections and substantially opaque portions corresponding to the highlight sections of the original drawing, making from said half tone and line mask negative by opaquing the transparent line portions of said negative a half tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections of the original drawing, making from said half tone mask negative a half tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight and line sections of the original drawing by preparing a photographic print of said half tone mask negative, superimposing said half tone mask negative and said half tone mask positive onto said drawing in either succession, and photographing said drawing on a light-sensitive photographic material through each of said superimposed masks separately in such a manner that a half tone screen is interposed between said drawing and said lightsensitive material when the drawing is photographed through the hall tone mask negative.-

21. In a process of producing a drop-out half tone and line negative from an original drawing having highlight, line, and tone sections, the steps of making from said drawing a continuous tone negative on a photographic material consisting of a light-sensitive layer on a transparent base, treating said continuous tone negative while still wet with a photographic reducer until the tones of the tone sections disappear, fixing, washing, and finally drying the thus produced half tone and line mask negative having substantially transparent portions corresponding to the tone and line sections and substantially opaque por tions corresponding to the highlight sections of the original drawing, making a half tone and line mask positive having substantially opaque portions corresponding to the tone and line sections and substantially transparent portions corresponding to the highlight sections of the original drawing by preparing a print of said half tone and line mask negative, making from said half tone and line mask negative by opaquing the transparent line portions of said negative a hali tone mask negative, superimposing said hali tone and line mask positive on said original drawing, photographing the same through said superimposed mask positive on a light-sensitive photo graphic material, removing said mask positive, superimposing on said drawing said half tone mask negative, interposing between said superimposed drawing-mask negative assembly and said light-sensitive photographic material a half tone screen and photographing said drawing through said mask negative and said half tone screen on the light-senstive material without altering the relative position of the drawing and the light-sensitive material during the successive photographing of said drawing on said lightsensitive material through said masks.

22. In a process of producing a drop-out half tone and line negative from an original drawing having highlight, line, and tone sections, the steps of making from said drawing a continuous tone negative on a photographic material con sisting of a light-sensitive layer on a transparent base, treating said continuous tone negative while still wet with a photographic reducer until the tone of the tone sections disappear, fixing, washing, and finally drying the thus produced half tone and line mask negative having substantially transparent portions corresponding to the tone and line sections and substantially opaque portions corresponding to the highlight sections of the original drawing, making from said halt tone and line mask negative by opaquing the transparent line portions of said negative a half tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections oi the original drawing, making from said half tone mask negative a halt tone mask positive having substantially opaque portions corresponding to the tone sections and substan tially transparent portions corresponding to the highlight and line sections of the original drawing by preparing a photographic print of said half tone mask negative, superimposing said halt tone mask positive on said original drawing, photographing the same through said superimposed mask positive on a light-sensitive photographic material, removing said mask positive,

superimposing on said drawing said hall tone mask negative interposing between said superimposed drawing-mask negative assembly and said iight-sensitive photographic material a half tone screen and photographing said drawing through said mask negative and said halt tone screen on the light-sensitive material without altering the relative position of the drawing and the light-sensitive material during the successive photographing of said drawing on said light-sensitive material through said masks.

23. In a process of producing a drop-out half [one negative from an original drawing having highlight and tone sections, the steps of making a half tone mask'negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight sections of the original drawing, making a half tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight sections oi the original drawing. photographing the original drawing on a light-sensitive photographic material first through said halt tone mask positive, photographing said original drawing again on the same light-sensitive material through said halt tone mask negative and a half tone screen interposed between said mask negative and the light-sensitive photographic material, and then placing behind said hall tone mask negative a light-reflecting, preferably white, sheet, and photographing said white sheet through said hali tone-screen and half tone mask negative.

24. In a process of producing a drop-out half tone and line. negative from an original drawmg, having highlight, line and tone sections, the steps of making a half tone mask negative having substantially transparent portions corresponding to the tone sections and substantially opaque portions corresponding to the highlight and line sections oi the original drawing, mak ing a half tone mask positive having substantially opaque portions corresponding to the tone sections and substantially transparent portions corresponding to the highlight and line sections of the original drawing, photographing thereafter the original drawing on a light-sensitive photographic material first through said half tone mask positive, photographing said original drawing again on the same light-sensitive material through said halt tone mask negative and a halt tone screen interposed between said mask negative and the light-sensitive photographic material, and then placing behind said half tone negative at light-reflecting. Preferably white, sheet, and photographing said white sheet through said half tone screen and half tone mask negative.

LASZLO ZUKMANN.