I suspect the fuzziness was a result of a poorly formed and likely too
large hole. If you check the web resources on this subject, you will see
how important a very smooth and thin edged hole of proper size is. And
how relatively difficult such a hole may be to produce. The optics are
based on diffraction at the edge of the hole (The very thing that causes
loss of sharpness at very small apertures in lenses!). The bigger the
hole, the less of the total light is properly diffracted and the fuzzier
the picture. Since it is the interaction of the light waves with the
edge of the hole that does the work, the accuracy and smoothness of the
circle is a very important factor in performance. In theory, the edge of
the hole should also be as thin as possible, hence the techniques that
abrade a hole in thin material.
Moose
Lama-Jim L'Hommedieu wrote:
I made a pinhole camera with the "objective" about 1" from the film plane.
I poked a hole in aluminum foil and mounted it on a cardboard tube (okay, it
was a toilet paper roll!)
I made 4 film guides with pushpins, and loaded it with a 90mm stip of Tri-X.
It worked but I was only able to make a contact print
24mm x 90 mm. It's probably just as well because even at that size it was
blurry and of course, the cylindrical shape of flat film
plane gave me additional distortion.
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