Welcome to SDC agent 99.<br /><br />Several points worth noting<br /><br />The Viking images are not TV pictures. They are still images. Furthermore the camera technology is different to conventional TV cameras<br /><br />Secondly, without calibration colour reconstructions can be wrong. We only get true colours on TV because these are being monitored and corrected. Remember test patterns?<br /><br />Third, the first image from Viking showed a pinkish sky. <br /><br /><i>Before the flight, the cameras had been calibrated and the sensitivity of each sensor-filter combination determined. "Qualitative tests indicated that simple normalization of the voltages for the three color channels was sufficient to produce reasonable color images. In making that judgment our attention was generally directed to saturated colors in the natural scene and test target." When the first color data were received, Mutch's specialists used the same normalization techniques to calibrate the image. "The result was surprising and disquieting. The entire scene, ground and atmosphere alike, was bathed in a reddish glow. Unwilling to commit ourselves publicly to this provocative display, we adjusted the parameters in the calibration program until the sky came out a neutral gray." The soil and rocks demonstrated good contrast, and the colors "seemed reasonable." This was the picture released eight hours later. "But in our chagrin," Mutch recalled, "the sky took on a bluish hue during reconstruction and photo-reproduction. The media representatives were delighted with the Earth-like colors of the scene."<br /><br />While the television and newspaper reporters hurried to get this color print before their respective audiences, continued analysis supported the reality of an orangish tint throughout the scene. The atmospheric coloration was due to the presence of suspended soil particles in the thin air. Mutch recalled: "Several days after the first release, we distributed a second version, this time with th</i> <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em> Arthur Clarke</p> </div>