Digital ICE and Dust Removal: Dust Won’t Pass!
It is the first time that EPSON implemented in its scanners the software-hardware system called KODAK/ASF Digital ICE and developed by engineers from Kodak’s Austin Development Center (this division is known under the name of Applied Science Fiction). Digital ICE technology is not new and has long been employed in specialized scanners from other manufacturers but the very fact of its use in a SOHO-class device, the EPSON Perfection 4870 is, is a kind of novelty by itself.
This system deals with various image defects caused by dust, scratches and so on (i.e. physical defects of the original). The system works with transparent (Digital ICE for Films) as well as with opaque (Digital ICE for Prints) types of the original. Let’s learn some specifics about this technology.
Processing Films: Digital ICE for Films
It is no secret that the scanning of slides requires great care. It’s very hard to make the surface of the original absolutely pure: ubiquitous specks of dust are literally attracted to films, thus making necessary the time-consuming post-processing of the scans. A dust mote, quite invisible to the eye, transforms into an elephant in a high-resolution scan. If you’ve ever tried it, you know that the standard way of dealing with dust (in an image-processing program) takes much time. The Digital ICE for Films technology solves this problem to some extent. When scanning transparent originals, this technology uses a fourth additional channel called defects channel. To reveal mechanical damages on the film and gather information about them, the surface of the original is once again scanned in the infrared range. With this info on hands, the computer performs image retouching, but only on the damaged areas. Digital ICE for Films doesn’t work with usual black-and-white films as well as with Kodachrome 64 Professional films.
Processing Photographs: Digital ICE for Prints
Digital ICE for Films may be considered as a technology “ported” in the “as is” way from specialized slide-scanners, but Digital ICE for Prints employed in the EPSON Perfection 4870 PHOTO scanner is “native” for flatbed scanners. It allows working with opaque originals, finding dust, scratches and other physical defects. As I mentioned above, films are scanned in the infrared range to reveal such defects. Photographs are dealt with in another way. The scanning process takes two passes with two light sources for photographs. The surface is illumined with two light sources positioned under different degrees and reflects different shadow patterns, depending on the artifacts of the original. This information is then given to the computer which finds and compares discrepancies and performs necessary retouching.
Dust Removal: Software Cleanup
Besides the hardware technology for cleaning the image up, the EPSON Perfection 4870 uses another method of avoiding mechanical defects, using the software Dust Removal technology. By the way, you should note that Digital ICE is the only of the two technologies to work with snapshots. Then, Digital ICE is better at removing defects, but it needs more resources and time than Dust Removal. Besides that, Digital ICE doesn’t support certain types of film like black-and-white negatives, very popular just a few years ago. The user can choose the necessary method depending on his/her own demands on the quality and speed of scanning.
You enable the above-described technologies in the exclusive scanning program, which is described in the next section.