January 1999

Digital Dustbuster

By Technology Review

Remember when hisses and pops were part of the audio experience? Fewer and fewer people do, now that CDs have made near-perfect sound reproduction commonplace. But technology has not been as kind to our eyes. Dust, scratches and fingerprints continue to mar photographic film. Fixing these images now requires either tedious manual touch-up of the negative or slide, or electronic processing that alters the underlying image.

Austin-based Applied Science Fiction has devised a way to erase these flaws. The technique relies on a film scanner's ability to focus precisely on each dye layer. The system produces separate signals for the yellow, magenta and cyan layers. A fourth "defect channel" is derived from light focused on the film's surfaces. A proprietary algorithm applies this correction to yield a clean electronic image within a few seconds. Nikon has licensed the technology for its film scanners.