Q. Why do scientists need to know about this?

A. Because not long ago, researchers from South Korea had to retract papers published in Science because the photographs used to prove that human stem cells had been cloned were effectively Photoshop-cloned, and not laboratory-cloned. There have been other recent cases, too. And today, in science, more and more, photographs are the data. The Federal Office of Research Integrity has said that in 1990, less than 3 percent of allegations of fraud they investigated involved contested images. By 2001, that number was 26 percent. And last year, it was 44.1 percent.

Mike Rossner of The Journal of Cell Biology estimates that 20 percent of the manuscripts he accepts contain at least one figure that has to be remade because of inappropriate image manipulation. He means that the images are not accurate reflections of the original data. Rossner estimates that about 1 percent of the papers have some piece of image data that is downright fraudulent.

Q. Where does he get his figures from?

A. Mike has a full-time person who looks at every image supporting accepted manuscripts. Other biologists tell me anecdotally that many images in journals are regularly touched up to improve contrast or to remove little imperfections. The journals are, in essence, doing the same things fashion magazines do. Some of it is legitimate. In other cases, they are crossing the line.

Q. Are there policy changes that you think scientists should be considering?

A. I think it’s very hard to define inappropriate manipulation. Sometimes you can change 30 percent of the pixels in an image and it won’t fundamentally change anything. At other times, you can change 5 percent of the pixels and it radically changes meaning. I’m not a purist. I think there’s room for cropping, adjusting, contrast enhancement, but I want to know what was done. I think journal editors need to see the unadulterated, unretouched original images.

Image Credit... Caleb Kenna for The New York Times

No. 2, the scientific community as a whole needs to come out with a well-thought-out policy on what is and isn’t acceptable when it comes to altering photographs. And this is something that must be refined, updated and changed as the technology changes. The journals are probably going to have to hire more staff. That will slow down the publication pipeline somewhat. But the cost of these scandals is too high. They undermine the public’s faith in science.

Q. You make software to detect forgeries. How do you design your programs?

A. I think like a forger. I spend a lot of time in Photoshop making digital forgeries to learn the tools and techniques a forger uses. We’ll make a composite photograph of two people and ask, “How do you manipulate this photograph to make it compelling?” By working backwards, we learn the forger’s techniques and how to detect them.