Sigma publishes 2 white papers describing how the Foveon image sensor captures images in the Sigma SD14 digital SLR. (Note that availability of the SD14 has been delayed until late February or early March.)  In the papers a comparison with conventional image sensors is made and you will find information on how this relates to "pixel count" and how it may affect image and color resolution. The more technical version of the papers discusses the adaptation of camera test procedures to do justice to this unique image sensor... Read the full article here