Making Enlarged Negatives and Positives on High Contrast Litho Film Most People Associate the Word “Film” with a Negative Image That Cones from the Camera

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Photo 13 Foothill College Kate Jordahl Making Enlarged Negatives and Positives on High Contrast Litho Film Most people associate the word “film” with a negative image that cones from the camera. In the same way, the word “print” is associated with a positive image on paper. Either a positive or a negative image can be recorded on either paper or film. When working with litho film materials, it becomes necessary to transfer images both positive and negative. Most continuous-tone and litho films are negative-acting materials and will reverse the tones in the image they receive. Actually, to produce a final high-contrast print from a continuous-tone original negative, two intermediate steps are necessary: a positive image is made by printing the original negative onto litho film; then that film positive is transferred by contact print to a second piece of litho film. The resulting high-contrast negative can be projected (or contact printed) onto enlarging paper, sensitized paper or a sensitized fabric for a Final print. High Contrast Litho Film You will need to select an original negative from your file or shoot a new one. Then follow this procedure: 1. Dust your original negative very well. 2. Place your original negative in Enlarger. If you are making an enlarged positive to then make an enlarged negative, your positive must be the size of your final image. If you wish to enlarge these positives or negatives later, make your enlarged positive no larger than 4x5”. Project the image onto a white piece of paper about the same thickness as the litho film. Focus. 3. Mark the edges of the paper on the baseboard with drafting tape so that when you remove the paper, you will be able to place the litho film correctly. Focus image on paper. Remove the paper. Dust the glass. Place the litho film on the baseboard emulsion side up. Close the lens to F8 or F11. 4. Make a series of test strips as you would in making a print. Keep count of how many 5 second intervals you use. 5. Develop the film in a tray of A/B Developer (The developer has a two hour life.) or dilute paper developer. Develop emulsion side up with constant agitation for 2 1/2 minutes to 3 minutes. If the image comes up too fast, reduce the exposure and try again. If there is insufficient density after 2 1/2 min. of development, then increase the exposure time. 6. Stop bath the film, then fix the image. Fixing time will be twice the time it takes for the light areas to clear. (Approximately 2-3 minutes.) The test can then be inspected under white light. (remember you must use film fixer which is 1:3 concentration, not 1:7 like paper.) 7. After determining the correct time make a full sheet exposure of the image. Process it as regular film: developer, stop, fix, hypo clear, wash. Hang it to dry carefully in the dryer. 8. When the litho film positive is dry, contact print it onto another sheet of lith film emulsion to emulsion and process it as before. Make a test strip and then use the best time to make a full sheet negative. Photo 13 Foothill College Kate Jordahl

9. If you are now going to enlarge the negative and positive, trim them to fit a negative carrier and make enlargements on to photo paper. If your film is larger than 4x5”, make contact prints onto photo paper. Hints • Film is much more sensitive to fingerprints and chemical mars.Work with care and use your towels. • A small piece of dust on the original positive will continue to multiply itself through the entire process. Study your positive carefully and clean your negative diligently. We will learn to use opaque touch up, but it makes spot toning look easy! • The film will be fragile when you have dried it. Have clean plastic pages available and carefully slip the films in and out. Photo 13 Foothill College Kate Jordahl Tone line Conversions “Ortho films can be used in nonstandard ways. When developed in weaker developers (conventional film or paper developers using Elon, diluted from 1:1 to 1:4) the emulsion re- mains inherently high contrast, but the slope of the characteristic curve will be lowered. Density changes can be controlled to provide useful tones. Dilute paper or film developers will produce a vigorous but full-scale continuous tone image on the ortho films.The contrast characteristics are suitable for what are called “tone line” conversions. These are produced when changes in density are used to create line information. The effect is to transform smoothly changing tone into strictly linear patterns. Such a transformation is used in silkscreen and lithographic printing, and can also be applied to photographic etching. The more texture in the original, the more detail there will be in the conversion. Untextured areas of the original appear white or black.” Handbook for Contemporary Photography Arnold Gassan Procedure Make an enlarged negative and positive: 1. Review your contact sheets and select an interesting image with lots of texture. En- large this onto litho film using the procedure from “Making Enlarged Negatives and Positives on High Contrast Litho Film” except process the film in paper developer diluted 1:2. This will give you a film positive of high contrast but will a full tonal range. To judge your exposure, view it as a transparency—there should be full shadow detail. Contact print the dry film positive to a sheet of litho film (emulsion to emulsion) and process it in the same manner. Now you are ready to produce the tone line conversion: 2. Tape the negative, emulsion-side down, to the glass of your contact printing frame. (Use transparent tape.) Place the positive over the negative, emulsion up and bring them into exact register. Tape them down. “The emulsions are assembled into a sandwich, in register but with the emulsions separated. If you view the assembly on the light table, it will appear nearly balanced with the positive image a bit stronger than the negative one. The sensation is that of looking at a very dull and flat print.” Handbook for Contemporary Photography Arnold Gassan 3. In the darkroom place a piece of litho film under the positive/negative sandwich and close the printing frame. 4 Set the enlarger for 11x14” prints at F8 and the timer for 10 seconds. 5. Hold the frame under the enlarger at a 45’ angle and expose the slanted frame. Turn a quarter turn and expose again. Repeat for all sides. ”Light passes through the slots left between positive and negative images in register but separated by two thicknesses of film base. Properly exposed and developed the film will blacken where the image was exposed between the positive and negative emulsions and remain clear elsewhere.” Handbook for Contemporary Photography Arnold Gassan Photo 13 Foothill College Kate Jordahl

6. Develop in Litho(A+B) developer. If the image appears too soon the film is overexposed or the total sandwich density is too thin. Try shortening your angled exposure or start over with denser original films.

A simplified schematic illustrating why slanting light produces a line density in the toneline conversion: either the positive or negative originals block direct light, and only where there are passages seen at a slant, caused by the separation of the silver images by two thicknesses of film base, is a high-contrast latent image produced. Photo 13 Foothill College Kate Jordahl Bas-Relief Bas-relief is a technique which gives the illusion of a three dimensional sculptural image resembling a wood cut or low relief sculpture lit from one side. Optimum results with bas-relief can be achieved using sharp, relatively even-contrast negatives with a few bold dominant forms. Procedure 1. Contact print your negative to lith film. This positive should be relatively equal in density to the original negative. (You may want to use a densitometer to balance the density.) Use lith film processed in paper developer to create the positive and use dilutions of any- where from 1-2 to 1-12. A good starting point may be 1 part developer to 7 parts water. 2. Next sandwich the positive and negative together, emulsions to emulsion. When they are in register, (examine them on the light table), you should see a uniformly gray or black surface since the negative half cancels out the positive half. 3. Now move the film pieces slightly out of register—this reveals a line image on the borders of the dominant forms in the image. Varying the degree and direction of offset will alter the width and position of the lines. Once a position is selected, tape the edges of the negative and positive together and, if possible, place between two small sheets of glass and place the glass in the enlarger. 4. Enlarge the sandwich. Varying the grades of paper used can produce bas-relief image with or without intermediate graytones. Select the one that looks best with your subject. Bas-Relief Slides can be made by contact printing the negative onto lith film and project- ing the sandwiched negative and positive in a glass slide mount.