The heart of the SD1 Merrill is its sensor, which uses Foveon technology. According to Sigma, a Foveon sensor provides a better image than the sensors in other digital cameras, which use a color filter array (CFA) – a mosaic of red, green and blue pixels in a checkerboard-like grid overlaying the image sensor. The Foveon sensor employs direct imaging involving three separate layers of pixels, one each in red, green and blue. This results in the Foveon sensor being able to capture more color information. Further, the absence of the grid system means the camera does not require the low pass anti-alias filter used in cameras with CFA sensors, which should further improve the image. Sigma claims that, due to its use of Foveon technology, the 15.6 megapixel APS-C X3 sensor of the SD1 Merrill is the equivalent of a 46 megapixel sensor. To interpret the information produced by its Foveon sensor, the SD1 Merrill uses two TRUE (Three layer Responsive Ultimate Engine) II processors, and to move this information to memory the SD1 Merrill requires a fast Compact Flash memory card rather then the SDHC cards used in most DSLRs. The result should be outstanding image quality. Other than these factors, the SD1 Merrill appears to be a conventional mid-level DSLR, with some features that work well and are very useful, but with some curious omissions and some annoyances.
- Excellent build quality
- Useful quick-set menu
- Excellent image quality
- AF problems in low light
- Frequent writing to the memory card
- Lacks video, live view, top LCD
The SD1 is well-built and produces excellent images with its Foveon sensor. Unfortunately, it's slow write times, AF issues and lack of several features leaves us wanting more.
Read Our Full Review: Sigma SD1 Merrill Review