my daughter made a pinhole camera for a science project.
actually, her project investigated the relationship of pinhole
to focal length... as well as a 10 year old could.
to measure the pinhole we did this:
1. punched a hole in a piece of paper with a paper punch
2. measured the hole with a ruler in mm
3. put the hole in the enlarger, projected the hole and measured it
this gave the enlargement ratio.
then we "drilled" pinholes in blackened copper foil, numbered each
and put them, one at a time, in the enlarger (which we hadn't changed).
we measured the projected pinhole and using the ratio calculated
the actual pinhole.
it worked. it was easy. since she had just started fractions she
found it interesting.
peter
_______________________________________________
Cameramakers mailing list
[EMAIL PROTECTED]
http://rmp.opusis.com/mailman/listinfo/cameramakers
