This is certainly LF, but pinhole. When I got a box of 5x12 x-ray film from a forum member in exchange for some bits and pieces I immediately saw a use for it. The resulting camera took months of trial and error to get to this stage, and it still needs work.
The film plane curve has a 5" (127mm) radius and I intended the film-pinhole distance to be the same but it ended up 135mm. The 0.5mm pinhole is on a movable plate to allow rise and fall of +/- 15mm to prevent curved horizon lines if the camera were pointed up or down. The good news is that the box is light-tight. But my big surprise on developing the test sheet was that the pinhole is too close: I see an image circle which I have never seen before on a pinhole camera.
The IC measures 270mm and drawing it all out on paper shows me that for the 128 degrees of coverage, I have to move the pinhole away from the film another 6mm to cover the full 12" of film. Hence the work that still needs to be done.
This was my first ever experience of x-ray film. Prior to testing the camera I cut a sheet of the film into 4x5s to test film speed and development. I found that a good speed was asa 100, and developing time of 8 min. in PMK Pyro is just right. I was pleasantly surprised with the results of the film, Kodak dental panorama film 198 7627. It's double-sided and oh, does it scratch. I don't have large enough trays for film of this size and used the cat litter trays I use for paper, which unfortunately have a small protruding dimple in the base - a no-no. No mor 5x12 negs until I get some proper trays. All in all I'm very satisfied with this project so far. The neg was over exposed so I need to re-evaluate exposure based on an aperture of f/270, and perhaps even change to a 0.4mm pinhole in order to improve sharpness. Here is a cropped image, lightly worked in LR.
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