Revealing mistake: In a scene where the canoes are shooting the rapids through a sheer cliff you can clearly see a stuntman climbing out of the water onto the rock.
Revealing mistake: Freeman Lowell has several cargo containers dumped off the spaceship, to make it appear the ship has suffered an accident. A wide shot shows the ship receding in the distance, with the containers rolling weightlessly in the foreground. As the foreground containers pass slightly in front of the more distant ones, they don't mask them; their images overlap. The containers were apparently composited into the shot with simple multiple exposures. (00:35:40)
Visible crew/equipment: When Spencer and Hill fly the second air plane, the studio headlights are mirrored in Hill's sunglasses. (00:20:35)
Factual error: When Craig is being tortured in "New York," a spy operative threatens to plug in the electric shock machine in a European socket/outlet, rather than an American-type socket.
Revealing mistake: When Itto puts the cover on the baby carriage it's obvious that the sudden downpour of rain is just a sprinkler placed in front of the camera. Pay attention to the cover, Itto's clothing and the puddle behind the carriage, they remain completely dry/untouched. (00:11:00)
Continuity mistake: After the scene when Aguirre and his men raid the cannibal village they get back on the raft. Aguirre approaches Ursua, lying injured next to his wife, and stares him down. Ursua's wife then stands up to Aguirre and grabs his arm. The shot then changes to a different angle and suddenly the horse appears behind Aguirre so that he can walk into it unexpectedly as he turns around. (00:53:30)