I haven't made one, but my daughter did. The film type is
unimportant. You probably want a film that is fairly large, ie at
least 120 and not 35mm. Or you can directly expose printing paper.
You get a reversed image, but it is direct. The f-stop is just the
pinhole-to-film distance divided by the pinhole diameter. The optimum
pinhole dimeter is give by .036 sqrt(si), where si is the distance
>from the pinhole to the film and all units are in millimeters.
The one my daughter made was just a shoebox with a piece of aluminum
foil with a needle hole for a pinhole, and black electrical tape for a
shutter. All interior surfaces were painted black. Photographic
paper (don't know the type, sorry) was taped against the back (with
safelight illumination in a darkroom), the lid put on, and taped with
masking tape, and the whole contraptions taken outside. They opened
the shutter for some number of seconds, (sorry again, but I don't
know), took it back in the darkroom, took it apart and developed the
-- David Jacobson