Operation Rheinübung, the morning of May 24th, 1942. German heavy cruiser Prinz Eugen has taken over the lead after Bismarck's  forward radar was damaged in action against the H.M.S. Norfolk and H.M.S. Suffolk. Concerned about aerial recognition, Kapitän zur See Brinkmann - pictured at the utmost left - decided to check out the aft Flak position. The Zeiss 10 x 80 20° he was manning brought the aft Zielanweisegerät - a Zeiss 8 x/24 x 90 so-called Stangenfernrohr, shown just below to the right - to target. This "ZAG" in turn automatically steered the ship's Flak rangefinders, mounted in the "Wackeltopfe". 

Research for the book series "The Eye of the Kriegsmarine", dedicated to the function of optical apparatus within German naval fire control systems up to 1945, is ongoing.