A lumen print forms a photogram image on black and white photographic paper under UV light (sunlight). Objects are placed directly on the paper and left for some time – minutes or hours, depending upon the strength of the sun – to burn an image onto the paper.

Olive Dean takes the lumen process one step further and combines black and white photographic paper with an additional coating of cyanotype chemicals.

Lumen UV exposure in clip frame.

Using a clip fram to hold down the seaweed a beach exposure was made.

Lumen after exposure.

An initial rinse in the sea.

Lumen having excess cyanotype solution washed off in seawater pool.

Left to drip dry.

Removing excess seawater from a lumen print.

The image can then be fixed or scanned to preserve the effect as the photographic paper would continue to react to any light.