Liquid light emulsion is light sensitive and can be used to coat objects in to be printed onto in the darkroom.
The following photos were taken by the Flickr user Francisco Navarrete Sitja.
As can be seen here, pretty much anything can be coated. Francisco has used rubble to print his images onto, creating an interesting effect when plied together (bottom).
Photograms are made by placing objects directly onto the light sensitive paperand then exposing it to light. The result is a negative shadow image varying in tone.
Man Ray Untitled (Rayograph), 1924
Man Ray was one of the first artists to use photograms within his art and named his own after himself, ‘Rayographs’.
Solarisation can be achieved by exposing a print or film to light when developing it. Man Ray found this our when his assistant Lee Miller accidentally turned on the light.
“Something crawled across my foot in the darkroom and I let out a yell and turned on the light. I never did find out what it was, a mouse or what. Then I quickly realized that the film was totally exposed: there in the development tanks, ready to be taken out, were a dozen practically fully- developed negatives of a nude against a black background.”
Man Ray, Nude, 1929.