Words & pictures Peter Bargh
Creative darkroom photographers who like to experiment should get hold of a pack of lith film. There are several interesting techniques you can try including his one - bas relief.
Lih film is a very high contrast film that reduces the tonal range so that primarily just black and white tones exist with minimal grey. By sandwiching and contact exposing full tone negatives you can create high contrast photographs.
Bas relief is where a high contrast negative and positive are sandwiched together very slightly out of register.
To attempt this you need a pack of lith film (it's sold in 5x4in sheets) and a pack of line film also sold in 5x4 sheets along with the usual collection of processing accessories such as trays, running water, thermometer, graduates etc that are mentioned in our basic darkroom guides in the archives and an enlarger to print the results. Lith film, unlike conventional negative film can be handled in red safelight conditions so you can see what's going on.
1 The first step is to make a contact positive from the negative using the line film. This makes a higher contrast result that can then be used to make the black and white lith positive. Some photographers ignore this intermediate stage, but doing it ensures you get a rich black and white lith rather than a grey washed out effect.
To ensure you obtain the correct exposure it's worth doing a test strip first (see ePHOTOzine archive for how to make a tests strip). As a guide this image needed 20 seconds at f/8 to produce a good positive.
2 Process the line image using normal print developer but at a high concentration and once developed, washed and fixed, leave to dry.
When dry, make a contact negative using the lith film (again make a test strip first). My exposure was f/8 for six seconds. This then needs processing in special Lith developer that comes in parts A and B that are mixed together to make a working solution.
When dry make another contact on lith film to produce a positive then process, wash and dry.
5 Now the fun bit by sandwiching both the Lith negative and positive together you can block out all the light making a black looking negative. If you slightly offset the pair light will come through creating an etched like result around edge details.
6 Stick a bit of masking tape down one edge of the pair to ensure they stay held in position and place them in an enlarger and make a print.
7 There won't be much light shining through onto the paper so the exposure may be over 20 seconds. This example took 40 seconds at f/11
- Make sure the negative you use is free from dust and scratches as these will be highlighted in the bas relief.
- Choose a subject with plenty of strong, well-defined lines such as tree branches, fences, ivy, cars, boats etc.
You can contact print the lith sandwich with another sheet of lith film to make a negative that can then be used without trying to keep the pair in register to produce a lovely black image with a white outline bas relief.