I traveled to a pond in the woods, and looked for a place to set up the camera. Given that the camera is a popup book, it was a challenge to find a place with an appropiate view so close to the ground. I found a suitable scene, and propped up the camera on my backpack.
The camera scene and setup.
In order to gauge the proper exposure length, I used an accompanying light meter app. The focal equivalent of this pinhole camera is f/228 and the photo paper sensitivity is equivalent ot ISO 10. This amounted to a 70 second exposure for the cloudy scene. There's only one chance for an exposure with this camera, given that you need to load the photo paper in darkness. It gives the process of taking a photo a gravity that isn't present even with a typical film camera.
To develop the photo, we need a process that renders the photosensitive crystals in the paper unresponsive. In this case, washing the paper with caffeic acid does the trick, and the acid can be found in coffee. However, the solution also must be a fairly strong base. So the developing solution is a combination of instant coffee (3 tsp), a stronger version of baking soda called washing soda (6 tsp), and 250 ml of water. After bathing the photo in the solution in a dark room for 3 minutes, and rinsing in pure water for another minute, the photo is ready.
Lastly, the photo needs to be processed. The captured image is a mirror of the real scene, both in geometry, and in brightness. This inversion and flipping is done digitally.