There are many different routes to the final negative. Here, Lloyd Godman gives an overview of the different techniques.
While many people working with alternative processes see the it as an extension of the traditonal photographic process, and strive to create near perfect prints via the traditional negative method, the potentials are much more diverse than this.
Original Film Negatives
Sheet film, 4×5, 8×10 or even larger can give highly detailed prints with a subtle tonal range when contact printed via the Vandyke brown process. Existing negatives can be used for this. A series of 120, or even 35mm negatives can be taped together to make a larger grid.
Continuous tone or line negatives and positives may be made in a copy camera or by projecting small negatives or slides in an enlarger onto sheet film on the easel. Any graphic arts film, line film or copy film may be used, such as Rapid Access, Kodalith, LPD4, QPD4, Kodak EL. See the high contrast film page for more details. These may be obtained from a lithographic supply company. Process film according to manufacturer’s instructions, OR for continuous tones on high contrast film, use a diluted paper developer such as Dektol (1:1 or even more diluted, such as 1:4 or 1:10), or use halftone screens when making the copy negatives. When making large negatives in an enlarger, it may be necessary to project onto a wall or floor, and to make an easel. Use a big piece of cardboard with the film size drawn on it, and some masking tape to hold film if necessary. Ortho films require a red safelight. Red cellophane may be used over a yellow darkroom safelight.
Photocopies usually allow the production of images onto A4 and A3 transparent sheets. They also allow the image to be tonally reversed meaning the image can be produced as a negative for printing back to a positive image on the print. If you are making several Mylar Negs that need to be registered for multiple printing, or enlarging a small image up very large with each section A3 be aware that the image will expand at differing rates depending how much black is in the image. This seems to be reduced if you allow the copier to cool down between each copy. Black and white photocopies produce a different type of transparency than a colour copier or a laser printer, so some experimentation might be necessary.
Ink jet prints
These can be printed onto transparent material from a computer file and make excellent negatives. The tonal scale can be altered on the computer to suit the printing technique desired.
Piece together several 8″x10″ sheets for larger images or A3 sheets of transparant sheet. Overlapping edges will show up as less exposed areas on print. If this is undesirable, cut pieces to fit exactly. Secure with tiny pieces of clear tape in unobtrusive places. Or, use overlaps and pieces of tape as part of the design. Thin paper printouts: These may also be used, but will need long exposures, approximately twice as long as needed for clear film. The paper grain might show up in the image.
Draw or paint on clear plastic or thin paper. Try black or red marking pen, India ink, film opaque, whiteout, litho crayon, black cattle marker, black oil pastel. Shadings in pencil may or may not come out well. Use paper or rubylith and cellophane cutouts.
Any object laid on the sensitised paper can be used to make photograms. Opaque materials will block the light and appear as blank spots; transparent and translucent materials will make areas of tones.
With emulsions that require an extended exposure to sunlight, oblique shadows from real objects out doors can be used to make images.