Q: How many engineering jobs let you take a van Gogh off the wall and hold it in your hands?

A: If you're both an electrical engineering professor and a research fellow at the Van Gogh Museum in Amsterdam, like Cornell's C. Richard Johnson Jr., you just might do this, says Susan Karlin of "IEEE Spectrum" magazine. A big concern of his is "fraud and how to detect it." Is that alleged van Gogh in hand authentic? Answering this can be done with high-resolution imaging associated with signal- processing algorithms that zero in at the brushstroke level. Currently, Johnson's focus is on canvas thread counts--the number of horizontal threads crossing a vertical line one centimeter long--to identify paintings from the same roll of canvas. This is telling for an artist who bought canvas in rolls, as van Gogh often did. Radio-opaque material in an X-ray helps reveal signature weave density. Johnson's team is currently distributing the software free to museums.

For me, he says, this kind of research is "like having a backstage pass. I go to conservation studios and can take a van Gogh out of its frame and examine it."

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