448 HANDBOOK OF PHOTOGRAPHY 



the original. This is projected to make a glossy 11- by 14-in. print. This print is 

 spotted and is rephotographed on an 11- by 14-in. plate. The final "blow up " is made 

 from this plate. The final sections are 40 in. wide and are developed in D-72, diluted 

 1 to 6 and kept at constant temperature. The prints are then mounted on three-ply 

 wood. 



If the mural is to be made up of portions of several unrelated pictures cut at odd 

 dimensions and sizes, the problem is largely artistic and not photographic. 



Murals are often made up of distinct portions of several prints assembled into a 

 pattern which may be regular, as rectangular, or it may be irregular, the individual 

 portions which make up the w^hole being in assorted sizes and shapes. 



Given a job of this kind the photographer often finds that he has thrust upon him 

 prints of varying color, varying tone range, varying degrees of gloss, varying size. 

 They may be the only prints available and the negatives may be unobtainable. 



The dimensions of the finished mural are known. The photographs are, therefore, 

 to be made into a design in miniature. The scale may be an inch to the foot or anj' 

 other convenient reduction. The photographer's or artist's design will be ultimately 

 copied on film and then projected into the final dimensions. If the original layout is 

 large enough to require more than one negative, there must be natural places where 

 one negative may stop and another one take up the design. There must be a line of 

 cleavage which bj' design is invisible but nevertheless there. 



Parts of the prints that are to be cut away are outlined with a razor blade, and the 

 actual cutting only goes through the emulsion or at least not very deep into the paper 

 itself. Then the print is torn so that the paper support tears away beneath the image 

 and leaves the latter verj^ thin. This edge may then be laid down on the adjacent 

 print and fixed in place. The better artists do not use an airbrush or other means of 

 obliterating the edge because of the difficulty in preventing the material from getting 

 under the feather edge (which may be thinned wdth sandpapering on the back of the 

 print) and from being more apparent than before the brush was used. 



The final design is photographed and projected upon mural paper in strips of the 

 proper dimension. These strips are processed like anj'^ other photographic paper 

 except that large tanks or trays are necessary. 



Transparent murals or mosaics may be printed upon paper which has an emulsion 

 on both sides such as Adlux, Translite, etc. Murals may be tinted or actuality painted 

 in transparent oils. This coloring is done after the mural is on the wall, and the 

 actual coloring is a job for an artist, not a photographer. 



Enlarged Negatives by Reversal. — -Where retouching must be done on miniature 

 negatives, the following method of making enlarged negatives is useful (see "Leica 

 Manual," 1st ed., p. 133.) The negative is projected upon process film or upon an 

 ortho film of somew^hat softer gradation. Develop the film, wash, fix, and bleach it in 

 potassium permanganate to which has been added silver nitrate; clear in sodivun 

 bisulphite, wash, and give second exposure. Then develop; again fix, w^ash, and dry. 

 Retouching can now take place upon this enlarged negative which may be used for 

 contact printing or which may be projected so that a larger print may be secured. 



Photographic Sketching. — A combination of photographic processes and of draw- 

 ing makes it possible to produce verj^ creditable sketches which resemble freehand 

 drawings. 



In one method, the negative is projected upon a sheet of white drawing paper where 

 the image is a negative. If the white lines of the image as projected are gone over 

 wdth a crayon or a soft pencil until all such white lines have been covered, a positive 

 sketch will have been made of the image on the negative. Now the drawn print is 

 photographed to the final size desired and photoprints are made from this 

 negative. 



