Imagine a planar array where each pixel gathers counts like an MCA (multichannel analyzer), mounted in some lead pinhole camera obscura.
This would give an extremely wide range of channels didactically illustrating the presence of calcium in gypsum (dryboard etc), visually show backscatter, etc.
Such pictures of modern and old city scenes would be mesmerizing to watch, partially seeing into buildings, the ground, ...
There's one in the Musée des Arts et Métiers in Paris — blew my mind!
[^1]: https://en.wikipedia.org/wiki/Cloud_chamber
Edit: turns out people make these at home all the time. Sick!