From Jordan Matelsky, on the first step in pen-plotter holography:
It was a truly bizarre experience deliberately smearing my fingers with oil and then touching my phone screen. Try it! Rules are made up!
I spent longer than warranted looking at the old CD jewel cases in Matelsky’s photos, partly out of nostalgia and partly because they turn out to be the medium. Matelsky turns the highlights moving across a greasy fingerprint into curves for a pen plotter to scratch into the plastic, creating an image whose apparent depth comes into view under a point light as you move your head.
Matelsky puts a pen plotter and old CD jewel cases back to work together, a delightfully useless collision of dead technologies for the pure fun of making holograms.