Sigma SD1 Merrill
Estimated Street Price: $2,299 (body only)
Sigma is the only camera maker to offer the unique Foveon X3 image sensor, which stacks pixels in three layers so that every pixel site records all three primary colors of light: blue (in the top layer), green (in the middle layer) and red (in the bottom layer). The Bayer-array sensors used in other DSLRs record just one color at each pixel site, producing the missing colors via proprietary interpolation of data from neighboring pixels. That results in moiré and other artifacts, which requires use of an image-blurring, anti-aliasing filter over the sensor. The Foveon sensor doesn’t need the blurring filter, so it produces higher resolution than Bayer sensors of similar horizontal-by-vertical pixel count.
The SD1 Merrill (named after the late co-creator of the Foveon sensor) eliminates the main drawback of the original SD1—the Merrill has a very competitive price. Besides its sensor and image quality, the SD1 Merrill’s best feature is the wide selection of lenses from which users can choose. Sigma is best known as a lens manufacturer and offers more than 40 for the SD1. These range from a 4.5mm circular fisheye and an 8-16mm superwide zoom to an 800mm ƒ/5.6 supertelephoto and the world’s fastest 500mm, the 200-500mm ƒ/2.8 zoom. Many feature Sigma’s OS optical image-stabilizing system. With the camera’s APS-C sensor, each lens frames like a lens 1.5x its focal length on a 35mm camera, so 35mm camera effective focal lengths of 12mm through 1200mm are available (plus the 6.75mm-equivalent circular fisheye).
The SD1 body is rugged (it’s the first splash-proof Sigma DSLR) and straightforward, designed for shooting still photos efficiently. There’s no video, or even live-view capability, but a bright pentaprism eye-level viewfinder shows 98% of the actual image area. There’s a 3.0-inch LCD monitor for playing back images.
STANDOUT FEATURE: The unique, high-resolution Foveon X3 image sensor.