Fig. 13: One of the two catfish that swam by above our heads. Had to crop the image a bit, because it was still too far away for the 20mm wideangle lens. River Rhine at Zollbrücke Rheinau Nikon D200; Δt=1/125 s; f=20 mm; f/2.8; ISO 100; 7 April 2018 10:09:22
