I wondered how the original was made. Did they paint the whole thing at once and then pleat it? Or was it made of two paintings that were cut up?

It seems to be much simpler than that; the prisms were solid and removable. So you just put them in a rack so all of one side is flat, and paint directly on them. When that painting is done, you rotate all the prisms to the next side and do the second painting.

https://en.wikipedia.org/wiki/Tabula_scalata

Thought the name seemed familiar; he wrote a number of the early MS .NET 2000's era of C#, VB.Net and other Microsoft Press books. Warms the heart to see an industry mentor bang out goofy stuff for curiosity and fun.

> The artist is unknown but the date of composition is given as 1580, which is several years before Mary was executed, so the transformation into a skull seems a little premature.

Mary Queen of Scots was imprisoned by the English for about 19 years before her execution and was pretty unpopular in Scotland during that period. So it is entirely possible that her morphing into a skull was intentional.

Now that he’s got it in a computer, it might be interesting to ask questions like: what’s the geometry that has the sharpest transition, while also preserving some sort of “good view” of the two subjects from a lot of viewing angles. I think this is not even a good phrasing of the problem yet, but phrasing the problem well is part of the fun.

I guess this could be interestingly image-dependent. In particular she’s quite pale, so I wonder how many surfaces could be shared between the two images.

The Brothers Quay did a fantastic (and predictably nightmarish) stop-motion exposition of anamorphosis: https://www.youtube.com/watch?v=cEfwbnMf3jM

Interesting and fun read, but I kept waiting for it to come back to logarithms. Seems there might be something there in the prisms?

Neat, it's like lenticular printing, but without the lens sheet

Neat!