I’ve been wanting to make a pinhole camera ever since I got my . It is after all, just a box built to high tolerances and what does a do best if not make a box to high tolerances - right!?
The math for the optics came from a man named Cyrus Arthur (The Science of Photography) who posted a YouTube video a few years ago. This was immensely helpful.
This gave me the depth of the box I needed and the diameter of the pinhole I needed to get the view angle I wanted, which was on the wide side. It comes out to the equivalent of an 18mm lens on a 35mm camera. The rest was measuring the dimensions of a standard 4x5 sheet film holder so that it fits nicely on the back of the box. It is critical to get these measurements correct because it effects the projection length from the pinhole to the film plane and the light-tightness of the camera.
I added some spirit levels to one short side and one long side so I can get level in both portrait and landscape views. There are also 1/4"-20 screw threads inserted in the sides opposite of the spirit levels to accommodate a tripod. I scored the path of light from the pinhole to the edges of the film plane to assist in framing the image. I inserted a step up ring on both the front and rear of the pinhole so that I could attach filters. There are a lot of other teaks I did to make this a proper camera like using stepped joints etc., but it would probably get too boring (if this is not already).
The pinhole is held in place with a retaining ring held in by magnets. I did this so that I have the option of changing the pinhole in the future. Here you can see an orange contrast filter attached to this retaining ring.
Here it is in the back yard taking some test shots.
And these are the test shots. This one was pointed at the sun to see the extent of the flare, which was significant, but kinda cool. The exposure was about 5 seconds and it was a windy day so you can see the leaves of the trees get fuzzy from the motion. It gives a dreamy rendering to the whole scene.
The back of my house. 9 second exposure. The maple tree is getting quite a workout from the wind.
For those of you who are darkroom/photo geeks, the film was Ilford FP4+ shot at ISO 125. The negatives were processed in HC-110 dilution B for 9 minutes. I scanned them and used NegativeLab Pro in Adobe Lightroom to reverse the image. Not a lot of adjustment was made. The exposures were pretty much as I planned.
All in all I have to say it is an incredibly empowering feeling to build your own camera and see those images appear intact on a negative. This is coming from a guy who has spent his life getting the “best” lenses and “best” camera bodies - and for what? To get some kind of optical perfection that does what? I finally feel free of the photo gear rabbit hole. Want a great camera? The best camera is the one you make!