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No photo finish in chips

It’s hard to find realistic color representation in digital photography.

I love my digital camera–an Olympus C-3040 Zoom. It allows me to take great pictures. It enables me to bypass the guessing game on settings and exposures. It gives me greater control over what I print. And it lets me share my pictures with loved ones practically in real time. It has turned my solitary hobby into a family obsession. I sometimes wonder what I did before I got it.

As much as I love my camera, it does have one major down side: The colors are not a realistic representations of what I shoot. With film, I wasted a lot of exposures and made a lot of mistakes. But the shots that worked accurately represented the scenes I shot, giving me an eerie sense of being in the scene, even in low-light settings. I rarely get that impression with my digital shots, except under ideal lighting conditions. The blues have a surreal quality; facial tones are rosier than in reality; primary-color areas appear without as much texture or contours as the real thing. In short, colors appear idealized.

I can make some adjustments in Photoshop, but I don’t feel confident that my adjustments make the pictures more true to life. I’m no Photoshop wiz, but I do know one principle of digital imaging: Garbage in, garbage out. If you start with a flawed image, you can make it look better, but you cannot eliminate the flaws altogether. Because flawless images with a 3.1-megapixel camera are rare, the process and results with my current system represent an entirely different medium than the film-based photography that was my hobby. The whole thing had me looking at film again as a way to get back what I lost.

Before I got my old Pentax out of storage, however, I thought I’d check out my options. The next level up in color quality includes 6-megapixel field cameras, which are marketed toward media professionals. (Our editor’s choice: The Nikon D1X, for around $5,000.) These cameras get me to 98 percent of film color accuracy, but they’re a bit pricey for me right now. If I really wanted to get serious, I could spring for a 16-megapixel studio digital camera or back that gets me that last 2 percent, at an enormous price. (Our editor’s choice in this category: Kodak’s DCS Pro Back–priced at just under $15,000, not including the camera.)

Perhaps readers will see a trend here. These cameras and backs achieve better color simply by increasing the megapixels. Digicams such as my Olympus use a single charged-coupled device (CCD), which filters out two of the three pixels it receives, taking pixels one color at a time in the red-green-blue (RGB) scheme. Thus, two-thirds of the data is thrown away, and the rest is fed through elaborate algorithms in the cameras’ digital signal processors (DSPs) for a “more accurate” image. These algorithms have improved tremendously over the last few years, but they are still prone to error. The more megapixels the algorithm has to work with, the better it will be at approximating true color. Some field and studio cameras have separate chips for red, green, and blue, which makes the algorithms simpler and produce very accurate color at a steep price.

Even though I can’t afford a more accurate color system right now, I’m not going back to film just yet. I’ll wait about 18 months for the next-generation digital-photography solution to become affordable. The whole landscape of digital imaging will soon change when production on a brand new kind of chip reaches the level of camera in my price range. Santa Clara, Calif.–based Foveon Inc.–the brainchild of Cal Tech’s Carver Mead that’s backed by the cash and intellectual property of National Semiconductor–can accurately take in all three colors in an image without filtering out any data. Test results show stunning color quality and resolution, without the cumbersome and expensive imaging DSPs found in CCD-based cameras.

The Foveon complementary metal oxide semiconductor (CMOS) chip emulates the retina of a human eye. The eye contains millions of combinations of three cones, each taking in red, green, or blue with a slight overlap. Foveon cofounder Richard Lyon mined National Semiconductor’s rich IP database, mostly created and stashed away by chip giant Richard Merrill, to find a CMOS chip that could be fabricated to emulate the analog human retina in digital silicon. The resulting chip is better, cheaper to manufacture, cooler, and it consumes less power than CCD chips on the market. And Foveon can build all the mechanical components of the camera (F-stop, autofocus, ISO number, etc.) into the silicon. The result is a solid-state camera that can process images as either still or full-motion. It is an artificial eye that can scale up to 300 megapixels–50 times the amount of data the human eye can receive.

The plan is for Foveon to use National Semiconductor’s chip fabs to create and sell the chips to such big camera companies as Sony, which is currently the No. 1 photo CCD chip manufacturer. Rumor has it that every camera company is scrambling for the chips, which should be in full production later this year. We should see Foveon-based cameras just in time for the Christmas season (Beth, honey, are you reading this?). But don’t expect cheap models until the camera companies can get their Foveon-based models up to full production. Bargain hunters will be able to nab current 6-megapixel field cameras for 4-megapixel point-and-shoot prices once the Foveon-based cameras are widely available.

The prototype chips are already out there. Foveon has had chips in high-end camera backs for some time. Foveon’s 16-megapixel X3 image sensor recently won the CeBIT Highlights 2002 Innovation Award–one of the most prestigious technology awards of the year. It is said to produce life-sized images that are eerily lifelike.

Foveon will truly change photography for good. No longer will taking photographs require any skill beyond an understanding of composition and lighting. Digital photography will become the standard by which film-based photography is judged. Film-based photography will still be practiced, just as painting is still practiced. But there will never be a need for film outside the realm of hobbyists. And I’ll never again wonder about the color realism of my digital photographs.

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