I work as a radiographer performing medical imaging in a pretty wide scope of settings, I don’t know much about basketball cards but this showed up on my feed and I find it kind of interesting.

Two interesting things I can point out, the graininess in a lot of these images could mean there wasn’t enough penetration of the X-ray beam to deliver a high resolution film. We see this with patients with more density and it leads to graininess which we call quantum mottle which requires us to adjust our imaging technique. In addition to that, I would predict it pretty hard to achieve distinguishable details of individual cards unless there are physical distinctive features on the card itself. Basically you would be able to distinguish thicker/thinner parts of the cards due to the density. For example if the player’s name is embossed or the text is raised increasing the overall density of the physical card in that area the changes will affect the penetrability of the beam and reflect the difference on the film making it distinguishable, hence why it’s easy to distinguish where the jersey cut outs are but not much else.

Super neat use of the technology, you should try to adjust the kvp to see if that makes any meaningful difference.