Hi again. I just finished my first session with my dark box and it indeed
works. I am smiling right now. I just need to work out two things yet. The
first being that tray processing would not be too feasible in this box. The
floor dimensions are 17 inches by about 12 inches. I was thinking of making
a vertical processing unit where I have tall troughs filled with the
chemicals and students would slip the paper into each trough using a clothes
pin or something. I am still thinking about that.
My second problem is something that I thought this group would be able
to help me out on. I was thinking of making a contacting printing unit with
a light in it. But trying to keep this project as simple and as low cost as
I can, I thought that my students could simply layer some glass, the paper
negative and the unexposed paper on the bottom of my dark box and then lift
the lid, count off the time needed for exposure and then close the box. This
would be fine if the exposure time were more than a few seconds, so I came
across another idea that might work. If you make a pinhole camera and use
photographic paper as a negative. Could one not also use the same pinhole
camera as a type of contact printer as well? If you placed your paper
negative together with an unexposed sheet of paper (emulsion sides together)
and place both sheets into your pinhole camera such that the paper negative
is between the pinhole and the unexposed paper, then place the camera in
front of a light source (say an evenly lit white wall), would this act as a
contact printer?
Also if this would work, might this also even out the exposure of the
resulting image. Forgive the none technical terms from the following. If we
make a pinhole camera that has a curved back of a known radius, then the
entire film plane is equidistant from the pinhole aperture. This should
result in a very evenly exposed negative. Yet, if we make a pinhole camera
with a flat film plane there will be portions of the film plane that are
further from the pinhole than others. The edges of the film plane would be
further from the pinhole and thus require more exposure to be properly
exposed. While in contrast the central region of the film plane being closer
to the film plane would require less time to be properly exposed. This would
result in a negative that usually has the two noticeable zones of exposure.
The central portion of the image is less exposed than the edge portion of
the image.
If this is true then by using the same pinhole camera as a contact printer
you would get the same gradation of light exposure. The resulting print
would be corrected for this unevenness of exposure. Or am in serious need of
some sleep? I hope that this made sense. And I hope the more "advance
pinholers" can help me with this technical aspect of my project. Ultimately
I would need to try this out, experience is how I best learn. Thank you for
your time and for any response to this question. CJ.
