Science in Focus: Shedding Light: Lights, Camera, Action

Exploring the Photochemical Effect

I. The Activity

You will be producing PHOTOGRAMS, shadowlike images made without a camera by placing objects on top of the sun-sensitive paper and exposing it to sunlight. An opaque or transluscent object will block out all or some of the photons. The result is a pattern on the paper below (rather like a shadow). When the paper is developed (generally by placing it in water) the photogram is permanent.

Materials

This activity does not use film, but instead using Sun Sensitive Paper (easily obtained in children's toy and craft stores)

Various objects such as:

  • dried flowers or leaves
  • seeds
  • glassware
  • lenses
  • salt, sand, spices
  • hair, wire, thread

Procedure

  1. Place chosen objects on the sun-sensitive paper.
  2. Place the paper in direct sunlight.
  3. The paper will change (many types do from blue to white and this takes about 7 minutes).
  4. Place the paper in the developer (in most cases a tray of water).
  5. The paper will darken and the shape of the object will be seen
Read on to find out how photograms are made in II.The Science.

I. The Activity <—
II. The Science
III. Resources