Kit #14: Stereo Pinhole Camera (2300 yen). Despite my recent whining, several of the Gakken kits work quite well right out of the box (something I’d remarked on for the Stirling engine kit). A case in point is kit #14. Pinhole cameras have been around since the invention of film, and pinhole viewers date back to the 4th century BC Greeks. Alhazen, in the 10th century, wrote his book on optics and built the first known “camera obscura”. Pinhole viewers projecting onto a sheet of paper are also the only really safe method of easily watching solar eclipses. There’s an entire website dedicated just to pinhole photography.
The concept’s simple – allow light to pass through a small hole in a sheet of paper (or even between the gaps in your fingers) and look at the resulting image at a good focus point on a backdrop some distance away (such as the sidewalk, a sheet of cardboard or a piece of white paper). For photography, use film as the backdrop and enclose it in an otherwise light-tight box. Gakken’s earlier kit – #3 – was a simple pinhole camera. Kit #14 goes a step further by having 3 pinholes; you can switch between having a simple panorama pinhole camera to having a stereo camera.
Stereo cameras are equally straight-forward. If you take two photos at the same time, but from slightly different angles, when you look at them one with each eye, you’ll get a kind of 3D effect as if you were looking at the original subject with your own eyes, but flattened out. The key is to have 2 sets of lenses in the camera, and trigger both shutters with one button. Stereo viewers were very common in the 60’s and 70’s, with sets of stereo pictures being sold at all kinds of tourist attractions, museums and art galleries. Gakken’s Stereo Pinhole Camera kit simply combines the pinhole and stereo vision ideas into one device, while also adding a dedicated photo viewer.
The kit’s probably one of the more complicated ones to build, with over 30 parts, but I completed it in an hour. A small lever rotates a panel back and forth to allow for 1 image per film frame, or two (using the central pinhole, or the two outer ones with the panel acting as a separator). Essentially, this is just a box with three little holes in front, 3 lens caps, and a crank for advancing the film. Even the frame counter is nothing more than an unnumbered dial with a little notch in it. The shutter is held open until the frame is fully exposed, and then is spring-closed. To keep the camera steady during the shot, a tripod is essential. Since there’s no lens, you have to pre-calculate exposure time based on the amount of ambient light present. It was fun building this camera, but I’m not sure how often I’ll be using it. Like the theremin, this one’s a lot harder to master its use than it is to build it.
The mook has quite a few stereo pictures, but they require cutting up the pages to use them. There’s a history of pinhole cameras, a couple of interviews with artists, and an explanation of optics and the nature of light. One article describes Midget trucks, first introduced to Japan in 1957. Another article shows how to take unusual pictures by folding light sensitive paper into square cones and exposing it directly at the subject. And, one of the regular writers visits a Japanese home brewer. There’s no real suggestion for customizing the kit this time, and the mook is a little boring. Normally, I resist cutting up the mook if possible (which is why I made the wind-up doll’s outfit (kit #16) from origami paper), but this time I didn’t have a choice, since I really wanted to look at all of the stereo photos. It’s been a long time since I’ve looked at stereo photos, and it was fun being able to do it again now.