No one makes a digital SLR like Sigma does. Ever since the company started making them, it has eschewed the CMOS and CCD sensors employed by most manufacturers and opted for three-layer sensors made by a company called Foveon. In Sigma's newest model, called the SD14, each of the three layers includes 4.7 megapixels. Sigma misleadingly markets the camera as a 14.1-megapixel camera, but while you can expect significantly more resolution than you'd get from a 4.7-megapixel camera, it's nowhere near what you'd get from a 14.1-megapixel CMOS- or CCD-based model. Fervent fans of the Foveon sensor say that the three independent layers yield better color accuracy than the other sensor technologies currently on the market, but we'll discuss that more a little later.
The SD14's body design is very similar to its predecessor, the SD10. While not the fanciest design, it is functional and has a comfortable, contoured grip. Sigma places most of the hard-button controls in logical, easy to reach places. Two dials atop the camera let you select the drive mode and exposure mode. The drive dial also doubles as the on/off switch. While their knurled edges provide a good grip, the camera did inadvertently turn on in my bag on more than one occasion.
Worse than that, though, are the menu-based controls, which feel like they belong on an entry-level point-and-shoot instead of a pricey dSLR. You can get to a menu for ISO, white balance, image size and image quality with one button press, but once there, you press one of the four-way control buttons to change each setting. Unlike some cameras, which let you move either way through the choices (moving from ISO 200 to either ISO 100 or ISO 400, for example), the SD14 makes you cycle forward through all possible choices. That means that if you want to go from ISO 200 to ISO 100, you have to press the up controller four times after pressing the button to access the menu.
Most shooting-related settings that aren't in the four-way menu are accessed by repeatedly pressing the Func button. That means that if you want to activate the extended ISO range so you can shoot at ISO 1,600, you have to press the Func button seven times, remembering to hold it down the seventh time, and then turn the selector dial that surrounds the shutter button to change the setting. Keep in mind that both the drive and exposure mode dials have more than half their possible click stops empty. Sigma could have easily put all these functions on these dials instead of making you remember how many button presses it takes before you have to hold down the Func button just so you can change the flash mode (the answer is three, in case you're wondering).
Outside of its sensor, the SD14 doesn't have many interesting or unique features. However, it does have a removable infrared-cut filter. If you didn't already know, almost all digital cameras have an IR-cut filter mounted in front of their sensors to remove the infrared spectrum of light, since it interferes with the camera's ability to capture the images we all love. However, just as you can load a film camera with infrared-sensitive film, you can remove the SD14's IR-cut filter, put the appropriate IR-photography filter on the front of your lens, and shoot IR photos. If you've enjoyed shooting IR photos with your film camera, the Sigma SD14 is one of the few digital cameras that will let you continue with that hobby.
Another interesting, but not unique, feature of the SD14 is that its built-in flash will let you wirelessly control one of Sigma's EF-500 DG Super SA-STTL hot-shoe flash units. The camera even includes three different wireless channels, in case you run into interference.
For a camera in this price range, I was a bit disappointed with the 2.5-inch LCD screen. Not only is it on the small side compared to the 3-inch screens that have been popping up on a lot of new SLRs, but it only has 150,000 pixels, while most 2.5-inch LCDs on competing cameras have 230,000 pixels. In fact, you can find 2.5-inch 230,000-pixel screens on a lot of point-and-shoot cameras these days. Image previews look coarse in places, due to the lower resolution, but then, you can't rely on any camera's LCD for a really accurate representation of your images anyway.