With a magnesium alloy dust and splash proof body the sigma sd quattro digital camera is a durable and rugged mirrorless interchangeable camera that can take advantage of the full line of sigma global vision lenses it features an aps c sized foveon sensor renowned for its imaging characteristics including sharpness of detail and nuanced colour tone and the latest dual true iii image processor the highly portable and fast processing sigma sd quattro digital camera uses a two mode autofocus