. . . . . . . . "A test target is a common feature on interplanetary landing craft such as the Viking Lander and Mars Exploration Rovers. The target is usually a visible marker or plate on the exterior of the vehicle within sight of the lander's imaging system (usually a CCD camera). The target possesses samples of primary colors and a grey scale. The camera uses this much like a photographer would use a on Earth; the color samples allow the camera to compensate for white balance and contrast. The target provides a visual reference as well, so that the initial orientation of the camera can be fixed."@en . . . . . . . . . . . "700417"^^ . . "Test target"@en . . . . . . . . . . "959973266"^^ . . "1102"^^ . . . "A test target is a common feature on interplanetary landing craft such as the Viking Lander and Mars Exploration Rovers. The target is usually a visible marker or plate on the exterior of the vehicle within sight of the lander's imaging system (usually a CCD camera). The target possesses samples of primary colors and a grey scale. The camera uses this much like a photographer would use a on Earth; the color samples allow the camera to compensate for white balance and contrast. The target provides a visual reference as well, so that the initial orientation of the camera can be fixed. On the Mars Exploration Rover, the target was designed with a pillar elevated above the main surface, so that it could be used as a sundial. \n* v \n* t \n* e"@en . . .