The long-awaited Sigma SD14 DSLR boasts a unique sensor and a whole lot of
megapixels. But how well does it perform?
If patience is a virtue, photographers shopping for a new Sigma DSLR are saints. After all, it's been three years since the last Sigma digital (the SD10), and it was more than six months between the announcement and availability of the new Sigma SD14 ($1,600, street, body only).
Clearly, a truly unique camera takes time. And the SD14 is unique. It's the first and only DSLR to use a second-generation Foveon X3 sensor, which has a 1.7X lens factor, boasts 14.1 megapixels, and is promoted as a color-accurate, detail-obsessed, low-noise alternative to the CMOS and CCD sensors used in other DSLRs.
For more on the X3, see the McNamara Report. For how the SD14 handled our standardized tests in the field and the Pop Photo Lab, keep reading.
BEYOND THE SENSOR
Aside from the sensor, this is the first Sigma DSLR with a new five-point AF system, JPEG and RAW file storage, pop-up flash, lithium ion battery, and 2.5-inch LCD.
We described many of the camera's features based on a preproduction model in our December 2006 Hands On. Built to tougher standards than most sub-$1,000 DSLRs, the SD14 is similar in size and design to its predecessors, the SD9 and SD10, which share its stainless steel frame and tough outer casing, but lack the pop-up flash. The less-expensive 10.2MP Nikon D200 rivals the SD14 in strength, and exceeds it by including weather and dust seals.
However, the SD14 has a removable dust/infrared cutoff filter in front of the sensor that keeps image dust mostly out of focus. Removing this filter enables IR shooting when combined with the right opaque IR passing filters, a very nice feature (for more on how to do that, see our SD14 Camera Hack). Another improvement: a beefed-up shutter mechanism that Sigma now rates at 100,000 shots, similar to the ratings of the Canon EOS 30D and Nikon D200.
The SD14 also packs a totally redesigned pentaprism viewfinder that no longer shows a dotted-line frame around the field of view (a holdover from Sigma's full-frame 35mm SLR days). Since all Sigma DSLRs sport a much smaller image sensor and a 1.7X 35mm lens factor, the new viewfinder is a welcome improvement and projects a bright, clear image with 98% accuracy and 0.90X magnification -- earning it Excellent ratings in both categories.
The new pop-up flash, with S-TTL metering and redeye reduction, is similar in range and power (GN 38, feet) to the Nikon D200. Flash sync speed is 1/180 sec, same as Canon's EOS 30D and slower than the 1/250 of the D200, but it falls to 1/60 sec when set to wirelessly control the optional Sigma EF-500 DG Super flash ($240, street). Though useful, the wireless control doesn't match the sophistication and multiple channels of the D200's Commander mode.
Most of the controls on the SD14 are well placed and easy to use. A new Quick Set button makes it very easy to change common settings such as ISO, white balance, resolution, and file format. But to navigate and change the camera's eight special functions (including the meter pattern, flash, and AF mode, indicated by tiny icons in the small data LCD on top) you must press the function button repeatedly to get to the right icon, then hold it while turning the stiff mode dial. Lift your finger off the function button even slightly and you have to start over.
Press the Quick Set button on the back for access to ISOs 100-800, a surprisingly narrow range (you can add ISO 1600 via a menu setting). The addition of mirror lockup helps reduce camera shake during the long exposures you might need to make up for the lack of higher ISOs. The camera has all the usual white balance presets and an easy-to-create manual setting, but lacks a Kelvin adjustment or fine-tuning for custom WB. In our field tests, the white balance occasionally shifted to the magenta side on JPEGs at ISO 400 and 800, especially when bracketing exposures.
Also missing: automatic image presets for action, nature, portrait, or night scenes. And while the SD14's 150,000-pixel LCD has a decent viewing angle, and its menus are easy to read and navigate, images aren't as sharp in playback as those on the Nikon D200's 230,000-pixel screen.
On older Sigma DSLRs, our biggest complaint was that we could shoot only RAW files. No longer. The SD14 lets you capture RAW or JPEG files (though not RAW + JPEG), with several compression and resolution options for JPEGs. We discovered, though, that the 14MP Super Hi JPEG format is merely an interpolated version of the 4.7MP Hi Quality JPEG, taking up much more storage space without offering a significant image-quality or print-size advantage.
Another gripe? While we could set the color space of JPEG images to Adobe RGB, the color space kept changing back to sRGB whenever the SD14 went to sleep or was turned off. (Sigma recently released a firmware download to fix it.)
You need Sigma's Photo Pro 3.0 software, which comes with the camera, to convert the SD14's RAW images to 8-bit JPEGs or to 8- or 16-bit TIFFs. While it's not the most sophisticated RAW utility -- lacking high-level controls such as curve, chromatic aberration, and lens distortion adjustments -- it does a far better job processing the SD14's RAW files than the current version of Adobe's Camera RAW.
Our image quality tests came down in favor of RAW files over JPEGs. In JPEG mode at ISO 100, the SD14 captures detail on par with an 8MP DSLR such as the Canon EOS Digital Rebel XT. Combined with an Extremely High color accuracy (9.9 Delta E), JPEGs earn an Extremely High image quality rating.
But in RAW, also at ISO 100, the SD14 performs more like a good 10MP DSLR, capturing about 10 percent higher resolution and Excellent color, earning it an Excellent image quality rating. Still, NEF RAW files from the $920 (street) 10.2MP Nikon D80 show higher detail. So this is not what you'd expect from a camera billed as having 14.1 megapixels.
At higher ISOs, the difference between JPEG and RAW files becomes painfully obvious. At ISO 400-800, RAW files are vastly superior to the JPEGs produced in the camera, most evident in shadows and darker-colored areas, which block up and get very noisy in JPEGs. In fact, by ISO 800, JPEGs made in-camera had such unusual colors and extreme shadow noise in multiple patches on our GretagMacBeth ColorChecker DC test target that we had to give them a thumbs-down -- even though the average color accuracy across all 180 patches tested Extremely High (8.5 Delta E), and noise in the neutral gray patch was Moderate (2.4).
Apparently, the SD14's internal image processor has a hard time converting high-ISO RAW data into JPEG form, while the supplied computer software handles the job more efficiently. The image processor also takes a glacial 8 to 10 sec to clear the buffer for another shot after a burst sequence of up to a mere six frames at 3 fps. That's not even in the same ballpark as the burst rate and capacity of competitive DSLRs.
In all, the camera handles well, opens creative doors with IR, and is technologically unique. But the promise of 14.1MP doesn't pay off. And given what you can find in today's DSLR market for $1,600, we see the virtue in shopping around.
Imaging: 14.1MP (effective, based on X3 sensor that has three RGB-sensitive layers of 1760x2640 pixels each). 12 bits/color in RAW format.
Storage: CF Type I and II, Microdrive. Stores JPEG or RAW.
Burst rate: Up to 6 Hi-quality JPEGs at 3 fps (tested using a SanDisk Extreme III 8GB card and LCD turned off).
AF system: TTL phase difference with 5 selectable AF zones with center cross-type. Sensitive down to EV -1 (at ISO 100, f/1.4).
Shutter speeds: 1/4000 to 30 sec plus B (1/3-EV increments).
Metering: 8-segment evaluative, limited-area, and center-weighted average metering. No true spotmeter. EV 1-20 (at ISO 100).
ISO range: 100-800 (in 1-EV increments) plus ISO 1600 via custom setting.
Flash: Built-in pop-up with S-TTL metering and GN 38 (ISO 100, feet). Flash sync at 1/180 sec. Dedicated hot-shoe.
Viewfinder: Fixed eye-level pentaprism.
LCD: 2.5-in. TFT with 150,000-pixel resolution.
Batteries: Rechargeable BP-21 Li-ion; 500 shots per charge (CIPA rating).
Size/weight: 5.7x4.2x3.2 in.; 1.8 lb with card and battery (body only).
Street price: $1,600, body only.
For info: www.sigmaphoto.com.
Accuracy: 98% (Excellent)
Magnification: 0.90X (Excellent)
• Canon EOS 30D ($1,120, street, body only): Has tough magnesium-alloy frame and faster AF system with better motion tracking, and faster (5 fps) burst rate. Produces less shadow noise at ISOs above 400, though the Sigma's RAW files show similar resolution and color accuracy.
• Nikon D200 ($1,340, street, body only): Tougher body with water and dust seals, superior AF system with better tracking, higher burst rates and NEF RAW + JPEG mode. Has superior noise control and dynamic range, plus smart Li-ion battery, but doesn't shoot infrared.