Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-l] pinhole camera



Typical pinhole cameras for classroom use may get more difficult and
more expensive as the film manufacturers quit making B&W photographic
paper. My understanding is that Kodak has already bowed out. I don't
know what Ilford and Agfa are planning.

Anyway, we used to do a pinhole camera project in general-education
physical-science class. It was a great hands-on lab experience.
Students had to design their own cameras to use photographic paper. You
need a darkroom for loading the camera and developing the print, but
since you use paper rather than film, you don't need total darkness.
You use the traditional yellow safelights both for loading the cameras
and developing the prints. The developer and fixer have traditionally
been cheap, and you use tray processing.

Why did we quit doing this? Our numbers got too large. We started
requiring all students to take the course rather than just having it as
an elective. So instead of 20 students a term taking the course, we
started having two or three sections of 36 for total enrollment of 72 or
108 per term. We didn't have sufficient darkroom space, nor did we have
enough time to supervise labs that were more "open-ended" (such as each
student designing and debugging her own camera).

Of course when we were doing the activity, current classes knew from
previous classes what good camera designs were. One design that always
seemed guaranteed to give great results was the "Quaker Oats" container.
That's a great place to start, and maybe even a great place to end up.
Armed with an empty rolled-oats container, you only need to decide how
you're going to make your pinhole and shutter. And even here, students
quickly learned that a pinhole in aluminum foil taped (black electrical
tape) over a bigger hole in the side of the oat container was a great
design, and the shutter can be made with more electrical tape if you're
clever enough to keep the sticky part off the aluminum foil.

I think you can find lots of info around on pinhole cameras. But try
starting with a rolled-oats container, and regular B&W photographic
paper 5"x7" or 8"x10" Develop in Dektol and fix with Fixer. Exposure
times are seconds... Anywhere from 5 seconds to 60 seconds depending on
light levels, size of container, and size of pinhole.

And enjoy the oatmeal. They say it's good for you. Except maybe not in
my case because I always made a ton of oatmeal cookies. They're
especially great with walnuts or pecans and dates (dates are even better
than raisins). Trust me, I have a lot of experience making lots of
cookies just so I could get the container.


Michael D. Edmiston, Ph.D.
Professor of Chemistry and Physics
Bluffton University
Bluffton, OH 45817
(419)-358-3270
edmiston@bluffton.edu