Gyotaku is derived from the Japanese words Gyo (fish) and Taku (print, rub). It describes the impression of a fish on rice paper or silk. Japanese fishermen developed this technique about 300 years ago to document their record catch. The fish was colored with ink of squid and covered with rice paper. Rubbing from above, an impression was taken, that showed the exact dimensions and shapes of the fish.

Olaf Altmann creates his Gyotaku images today with high quality acrylic paints on silk. Which guarantees color fastness and durability. Before being colored, the fish is specially filleted and can be almost completely consumed. Because for his Gyotaku, Altmann needs only the fins and skin of the one half fish which is used as a printing block. He places the half fish on a board, painting it detailed and cover it with a silk cloth. Now he feels the fish for through the cloth, creating his lifelike and life-size image. According to Japanese tradition Altmann has set itself the goal retouch after the actual print process not the image further. His special technique allows the fish to give a natural look without needing later editing and correction. For example, to let the eyes look realistic and alive, he paints pupil, iris and light reflection directly on the real fisheye before placing the cloth and rub. When all details are transferred the silk is carefully lifted. Finally, the Gyotaku image is stretched on a frame and signed. This unique piece of art shows us the fascinating beauty of our underwater world.