Create a character portrait of Dr. Sado from the 1974 anime Space Battleship Yamato. He is an older man with a rough, weathered appearance, featuring short, graying hair and a mustache. Dr. Sado wears a white lab coat over a dark-colored uniform, indicative of his role as the ship's doctor and engineer. His facial expression is serious yet compassionate, showing his wisdom and experience. His glasses rest slightly on the bridge of his nose, and he holds a medical tool or device in one hand. The background should depict the interior of the Yamato, with a focus on the ship's technology and engineering aspects, giving a sense of the high-tech environment he works in