Days to Centenary: 243
Today’s installment of Turing’s artistic legacy has a distinctly DIY, make-ist [Make magazine | NYC Maker Faire] spirit. Rupert Rawnsley of Cardiff, UK has made a lithophane of his hero (and ours) Alan Turing.
He did this with the upcoming Alan Turing Year specifically in mind, which just goes to show that no matter how many interesting official events the ATY will include, there are bound to be many equally interesting unofficial events and projects, created by Turing-elves like Rawnsley for their own enjoyment and that of other Turing-o-philes, tucked away in the corners of the world and just waiting to be found. If you have an unofficial event or project planned (or perhaps already executed), write me at firstname.lastname@example.org. Responses will be posted (unless you request otherwise).
Now, back to Rawnsley and his lithophane. “What the heck is a lithophane?” I hear you ask.
Put simply, it’s a transluscent 3D image that can only be seen properly when backlit. European lithophanes originated in the 1820s, although they may have existed much earlier in Asia (possibly as long ago as the Tang Dynasty in China, 618CE–907CE).
Here’s a vintage European lithophane in a specially constructed stand:
And how does one make a lithophane? Well, I have two answers. The first goes like this:
Lithophane, 19th Century Edition
Carve an image into warm wax, transfer it to gypsum (and sometimes then to metal if you want to make multiple lithophanes from a single mold). Then use this as a mold to cast a final version in porcelain. The resulting image will be somewhere in the range of 1.5-6mm thick.
The second answer, which uses the technology Turing helped create to update the procedure and shift much of the work to technology, looks like this:
Lithophane, 21st Century Edition
Take a black and white image and use a computer program (Bitmap zu IGES/STL Konverter) to translate it into a 3D relief image (this takes mere seconds), render the results in G-code (several hours), and then print on a 3D printer (several more hours). Rawnsley has helpufully uploaded his code for anyone who might be able to use it, along with images and technical information about the process he used.
The final product of the modern approach looks like this:
The sequence leading up to the result looks something like this:
Rawnsley’s project page is here.
Now that you’re part of the very exclusive lithophany clique, you may want to visit the Blair Museumof Lithophanes, have a look around an international selection of lithophanes at the bottom of this page, examine an alternative description of how to make your own lithophanes, or purchase a rare, never marketed, Elvis lithphone (oops, sold for US$350.00… there must be another one out there somewhere).
Until next time!