On Sunday, December 2, 2012 1:53:33 PM UTC-8, axolotl wrote:
A coworker bought a view camera, and while searching for glass wants to

take some pinhole pictures.

Get a bit of aluminum foil, fold into a stack with many layers (16 is good).
Stab the center of the stack with a pin.

Peel off layers of the stack until the hole size is right.

Mounting the foil, and protecting it, is left as an exercise.