The secret talents of duotones

When one's darling dearie works as a graphic designer at a print shop, the delicate and devilish intricacies of printing become a main topic of dinnertime conversation. In an effort to glean some useful duotonic tricks, I stumbled across this little piece of quite clever research.

This project addresses the special case of selecting inks for duotone printing, a relatively inexpensive process in which just two inks are used. Traditional duotone printing almost always uses black as one of the two inks. The resulting reproduction is an "enhanced grayscale" image: a grayscale image with a hint of the chosen accent color. We would like to use duotone printing to achieve full color reproduction. Our system takes an image as input and allows the user to select 0, 1, or 2 inks. The output consists of the remaining inks or inks that will best reproduce the image as a duotone and the appropriate color separations.

I mean, just look at these two scans:

CMYK reproduction of Degas' Women

duotone with PANTONE 144 and PANTONE 546

I'd never have expected 2-color prints to come out that good.

The paper's a good read too, with loads of easy-to-skip equations.

Now, anybody got a Photoshop plug-in based on this stuff?