New Technology Enables Astoundingly Accurate Artwork Reproductions
Color accuracy under different light sources. Courtesy of MIT CSAIL
Giclée is at once one of the most pretentious and profane words used to sell art. French for “spurt,” the term was adopted by Jack Duganne in the early 1990s as a way of adding prestige to the ink-jet prints he made using an extremely precise Iris printer. These “spurt” prints typically use the same CMYK (Cyan, Magenta, Yellow, and Key, or black) color model invented by Boston’s Eagle Printing Ink Company way back in 1906. But a team at MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) has developed a new printing process that could relegate both giclée and CMYK to the history books.
The new process yields better color accuracy under all sorts of lighting conditions, an achievement that could significantly improve what you find in both museum gift shops and on gallery walls. Applications include better replicas (for preventing wear and tear to original works) and higher fidelity images in prints, postcards, and books. The team at MIT also hopes the technology could make art more accessible.
“The value of fine art has rapidly increased in recent years, so there’s an increased tendency for it to be locked up in warehouses away from the public eye,” said mechanical engineer Mike Foshey in a statement. “We’re building the technology to reverse this trend, and to create inexpensive and accurate reproductions that can be enjoyed by all.”
Instead of setting a JPEG of Mark Rothko’s Orange and Yellow (1956) as your phone background, you could someday hang a print of it at home that’s indistinguishable from the original.
How it works
The new technology, called RePaint, uses a resin-based 3D printer to apply 11 different inks: cyan, magenta, yellow, black, green, blue, orange, red, violet, transparent white, and opaque white. There are 2D printers that use more inks—Canon’s imagePROGRAF PRO-6000, for instance, uses 12—but they can’t combine them with as much versatility due to ink saturation, which causes blotting.
RePaint, by contrast, stacks ink in layers “like the wafers and chocolate in a Kit-Kat,” according to the MIT researchers. Opaque white is used as a base, essentially playing the same role as the paper in 2D-printing, while transparent white is used to veil the other inks, making them less vibrant where necessary.
This stacking of layers is called “color-contoning,” and it’s used in combination with the tried-and-true 2D technique of half-toning, where tiny dots of different sizes, spacing, and hues are used to create a wider range of colors and shades.
To determine the right stack of inks to create each color, the team used a deep-learning model. They then tested its success on one of Claude Monet’s Water Lilies, as well as on original oil paintings by collaborator Azadeh Asadi made specifically to challenge their technology.
The resulting colors are four times closer to the original than the next-best technology, according to the researchers. Subjective perceptions back up the data, with CMYK prints looking noticeably muddier. RePaint also purports to solve the problem, common with 2D prints, of metamerism, where colors that match under one light source diverge under others.
“Our system works under any lighting condition and shows a far greater color reproduction capability than almost any other previous work,” said Changil Kim, one of the authors of the paper.
While the process has so far been used to recreate oil paintings, Foshey said it could also be used in the future to recreate sculptural works.
While its color reproduction already outperforms standard CMYK printing, the 3D-printed ink stacks still have room for improvement. The process struggled to produce cobalt blue, for instance, and couldn’t quite nail down cobalt violet, carmine, cadmium yellow, and gray. To improve their results, researchers plan to expand their ink library and create a painting-specific algorithm for selecting inks that would yield the truest colors.
They also stated that 3D-printing different textures and microgeography would allow them to recreate physical brush strokes and produce both matte and gloss finishes using the same set of inks—impossible in 2D-printing.
For those worried about a new generation of high-fidelity forgeries, Foshey said RePaint could also be used to introduce “anti-counterfeiting features.” (Of course, counterfeiters and pirates have been known to circumvent such features in the past.)
Researchers said that the cost of materials for their approach is “minimal,” but one major downside, at least for the time being, is printing speed. “It takes around one-and-a-half hours to print business-card sized prints,” Foshey said.
At that speed, printing Rothko’s 7.5-by-6-foot Orange and Yellow would take a little over 56 days.