I was growing tired of wide-angle shots, so I constructed a third pinhole camera from a shoe box, cut to about one third of its length. Keeping the box lid intact at the end allowed me to easily construct a flip-up paper loader along the back of the camera box. It seems to be very effective at sealing the box, and I put in some tabs to hold the photo paper in place – no curved photo-plane this time. I improvised the usual tripod mount with scrap wood and a piece of hardware from Home Depot.
I cannibalized the aperture (0.3mm) from my wide-angle camera to use with this one, even though all the formulae indicate that a 0.45mm pinhole is optimal: I have new ones on order, but I couldn’t wait. Rushing again… With a focal length of 5-inches, the f-number is about 425.
My first attempt with the new box was a shot of the USS Ling taken from down near the water, a great shot of the rusting hulk of a submarine, but I noticed that the aperture didn’t seem to be properly fixed to the camera body. Sure enough, in the darkroom, I got an all black print. 😦 I had made a too big hole in the box so that when I taped the aperture holder over it, I didn’t quite close it. It was hard to tape on without bending the camera wall since the hole was almost the same size as the aperture holder. I fixed this by gluing a sheet of matting over the original hole, with a smaller hole punched in it, over which I taped the aperture holder. The thickness of the whole deal is so little that I don’t have to worry about vignetting the image.
After the repair, the camera worked great. Perhaps a little light leak showing in the upper part of the image, but that might just be the bright sky with tree shade.
And a nice gothic shot of our town hall shot with my 0.2mm camera.