The New Low-Light Photography

	Parker J. Pfister/Parker J Photo
	Click photo to see more low-light shots.

Sharp, clean images lit by just a burning candle. Smooth, natural skin tones in dim, mixed lighting. Blur-free scenes shot handheld at 1/8 sec. Action frozen without a flash. Details in shadows without compromising color. Autofocus that locks on in the dark. Welcome to today's low-light photography.

Armed with the latest DSLRs, photographers can get shots that were all but impossible even a few years ago. And images taken in the most difficult situations have never looked so good.

The reasons? Increasingly sensitive image sensors, better image processing, faster and more responsive AF systems, improved exposure readings, refined white-balance settings, and near-ubiquitous image stabilization.

Although low-light performance has been improving incrementally across the board for the past few years, it has soared recently. ISO 3200 and even 6400 is increasingly common, digital noise shows up less, and higher megapixel counts let you apply noise reduction either in the camera or in postprocessing while maintaining plenty of sharpness in your images. No tripod? You can handhold to 1/8 sec or slower.

And, camera makers say, it's only going to get better, as photographers demand ever-superior performance from their cameras. Technology developed for pro-level DSLRs is trickling down to consumer models. At the same time, some sophisticated technology from compacts, such as smaller IS systems and white balance linked to faces in the scene, is migrating upstream to DSLRs.

"With film cameras, nobody expected to get high image quality in low light -- you accepted the grain and the contrast. But now you talk to photographers, and it's almost like they expect the same image quality at ISO 3200 or 6400 as at ISO 100," says John Knaur, senior marketing manager for DSLRs at Olympus Imaging America Inc.

Going forward, "low-light performance is going to be a driving challenge, and with it there will be changing mores and habits among photographers."

The pacesetter, at least for now, is the 12.1MP Nikon D3 ($5,000, street, body only), which can reach an astonishing ISO 25,600, 2 stops above ISO 6400, albeit with a lot of noise and less resolution. In our recent tests in the Pop Photo Lab, image quality was Excellent through ISO 3200 and still Extremely High at ISO 6400. The AF system took less than 1 second to lock onto a subject in a very dimly lit room (measured as EV -2 at ISO 100, essentially candlelight), much darker than was possible to focus in just a few years ago.

What does that mean for photographers? "Tough available-light situations that I once had to shoot at slow shutter speeds -- and justified in the name of creativity -- are a thing of the past," says sports photographer George Tiedemann, a Nikon-supported shooter, who used the D3 for the photo on the opening spread. "I can do things today that I would only dream about doing before."

The trends are evident not just in pro DSLRs but in advanced-enthusiast models we've tested recently. (For the relevant specs and our Certified Test Results for all of the DSLRs in the $1,000-2,000 range we've tested since last autumn, see the table on page 72.) Take, for example, the 10.1MP Canon EOS 40D ($1,140, street, body only). Its ISO range stretches to 3200, image quality for RAW files (converted to 16-bit TIFF) is Excellent up to ISO 1600 and Extremely High at ISO 3200, where noise tops out at Moderate. Indeed, the 40D produces about as little noise at ISO 800 as its grandparent, the 8.2MP Canon EOS 20D (tested in our January 2005 issue), did at ISO 200 -- and with far greater resolution.

While Canon traces this progress to its development of the CMOS sensor and DIGIC image processor (now DIGIC III) in 2000, both have been refined since then. For instance, "we increased the size of the microlenses over the individual pixels on the sensor and reduced the gaps between them," says Chuck Westfall, director of media and customer relationship for the Camera Marketing Group at Canon U.S.A., Inc.

He explains that pixels are sensitive to light only at the center, so using microlenses to focus the light onto that part of each pixel "increases the sensor's signal-to-noise ratio." At the same time, "the percentage of the pixel that's light-sensitive has increased with each generation of the sensor." And although Canon has shrunk the pixel size to fit more on a sensor, the light-sensitive portion has remained the same size.

Thanks to these and other steps, the $4,100 (street) EOS-1D Mark III, introduced a year ago, hits ISO 6400.
While Canon has been using CMOS sensors in DSLRs for many years, and Olympus has long used a somewhat similar Live MOS sensor, other manufacturers started putting them in their high-end models only recently. Indeed, every camera on the table on page 72 uses this kind of technology.