You say you didn’t have enough warning to order eclipse glasses, and now they’re too expensive to buy? Or maybe you did order some but they ended up being those retina-combusting knock-offs, and now you’ve got nothing to protect you during the partial phase of Monday’s eclipse? Don’t dump a ton of money on unobtainium glasses — just stick your head in a cardboard box.
You may end up looking like a Box Troll with the aptly named [audreyobscura]’s box on your head, but it really is a safe and effective way of watching the eclipse, or for gazing at our star anytime for that matter. It’s nothing more than a large pinhole camera, with a tiny hole in a scrap of aluminum soda can acting as an aperture. The pinhole in one end of a box casts a perfect image of the sun on a paper screen at the other end of the box. A hole for your head with a proper gasket around your neck — maybe the neck of an old T-shirt would be a bit more comfortable and light tight? — and you’re ready for the show. The bigger the box, the bigger (and dimmer) the image will be, so you’ll want to cruise the local home center for long boxes. Because walking around with a water heater box on your head is totally cool.
Really, though, Hackaday readers can’t say they didn’t know this was coming. We started covering this in January, we’ve got hundreds of eclipse meetups across the country, and we’ve even covered some citizen science opportunities you can partake in on Eclipse Day. If you don’t have your head in a box, that is.
Thanks to [Roger Guess] for the idea on this one.
Here’s something to show people who don’t realize the power of 3D printing. This pinhole camera has one moving part which reveals the pinhole, letting in light to expose the 4×5 film inside.
It’s a near perfect roundup of all the qualities a 3D printer has to offer. The build centers around a 4×5 film holder which can be acquired used or as surplus. This drives home the concept of having the power to replace parts (in this case the entire camera) that fit with existing pieces (the film holder). The picture above is big enough that you can see the layers on the pyramid shape, but the structural pieces around the frame also let the uninitiated see that you can print more than just solid blocks. And finally, since it’s up for download on Thingiverse its a good example of how the printing community shares and builds on each others’ work.
Does it take quality photos? We have no idea. So far we didn’t see any example pictures. But really, if you’re looking for top quality you might want to build your own digital camera. Here’s one that uses a 14 megapixel sensor.
With digital cameras in everything and film slowly disappearing from shelves, everyone loses an awesome way to learn about photography. Pinhole cameras allow anyone to build a camera from scratch and also learn about those crazy f-stops, exposure times, and focal planes that Instagram just won’t teach you. [Matt] put up a great tutorial for building your own pinhole camera, and the project looks easy enough for even those who are still playing around with their cell phone cameras.
For film, [Matt] used 120 film, a medium-format medium that is sill available for purchase and processing in some areas. Because [Matt]’s pinhole is relatively large and made out of very thin material, the camera could take very large pictures – much larger than standard 35mm fare. If you’re using a smaller camera projecting a smaller image onto the film, 35mm would be the way to go as it greatly decreases the difficulty of finding film and a processing center.
[Matt]’s camera is constructed out of laser-cut plywood. Because he’s producing extremely wide images with his camera (6 x 17cm), [Matt] needed to curve the film around the focal plane of the camera to keep the entire image in focus.
The mechanics of the camera are simple – just a pair of knobs to wind the film and a small metal shutter. [Matt] added a shutter release cable to open and close the aperture without moving the camera and had a wonderful camera perfect for capturing either sirs and madams or Civil War battlefields.