A camera samples an image area that includes an active region that encompasses a captured photographed image and an extended region. The extended region includes a reference object that is fixed to the camera and is sampled with the photographed image. An image of the reference object is referenced and used for one or more color calibration procedures, such as white balancing, black level calibration, and red and blue channel gains. In a multi-camera configuration, each camera includes a reference object and color calibration is performed for each camera to achieve near-seamless mosaic panoramic images.