Lumen printing is another camera-less process and belong to alternative processes area. It involves black & white or colour photographic paper and natural light. Apart of it we need organic materials or digital prints could be use for this process.
Lumen printing is solar photogram so the most important in this process is the sun. Any organic materials like flowers, cereals, and leaves we can find in our gardens or parks.
Lumen print by John Fobes
In darkroom or in adopted for this experiment place we place the chosen organic material or digital negative on the board and cover it by glass. Next we expose the board in sunlight. The exposure time is very different and depends on weather condition. In bright sunny day can take 30 min while in cloudy day the time may extend to 4 hours.
I used for my project black & white photographic paper, one digital negative and few composition created from flowers. I exposed both of them on the sun for the same time, which in this case was 1 hour. The day was bright and sunny. The organic composition works well while the one with the digital negative was a bit washed out and very little visible. Reason for this may be that the exposure time for this perticular composition was to short and also the digital negative wasn’t enough contrasty. After I removed the top glass from the boards with already exposed photographic papers I scaned the result and then moved to Photoshop to experiment more with the colours, textures and curves.
This is the final results
Gum Bichromate Photography
Gum Bichromate is very creative and inspiring alternative process. “Is a deceptively simple process which involves just a single light sensitive chemical, is developed in water, and can be printed on a variety of papers and other surfaces.” http://www.gumphoto.co.uk/about_gum.html The preparation (part I)
- One or more with high contrast images
- Sheets of Digital Transfer Film
I prepared the image in Photoshop and inverted it to negative looks like. Then I printed on Digital transfer Film.
The preparation (part II)
- Paper or other surfaces like canvas for example
- Scales to measure the chemicals
- Small mixing cups for combining pigment/gum sensitizer
- Frame board
- Working area
- Pigment concentration
After mixing the chemicals I coated the paper with the chemicals by using flat wide brush. I tried to do as quickly as possible and then I used hair-drier to dry the paper. Next step was to leave the paper in dark area to dray a bit more. After this process I could place one of my digital negatives and ready composition expose on the sun.
The time of the exposure again will depend on the weather but also on the sensitizer along of negatives and papers. My first try didn’t work due to much to long exposure (1,5 hour) in very bright sunny day. What else went wrong and I can think about is referred to the paper preparation and maybe not very good choice of negative. I will try to experiment again with Gum Bichromate in a near future and I will pay more attention to preparation procedure. I will try also to reduce the time of exposure but this will depend on the weather condition I guess.