Continuity mistake: When the camera shows the back of the truck, there are two soldiers on each side of the truck, plus the sergeant inside it. Following that, there were seven soldiers and one of them fell off the truck – there's a missing soldier in the scene. (01:25:50)
Continuity mistake: In the submarine dock of Geheimhaven, Captain Mohler is a man with dark hair in his mid or late thirties. But during the procession, he seems to be much older, with grey hair.
Continuity mistake: When the Nazis are aboard the Bantu Wind, in the full scene of the ship deck, Toht stands behind Belloq. But, after Marion tries to hit Dietrich, the camera focuses on Belloq, then on Dietrich again. Toht is not seen anymore on the deck.
Continuity mistake: When the Nazis are loading the Ark in the truck, you can spot Toht next to the left side of the truck, watching the scene. A few seconds later, he walks out of scene, apparently going to the car. However, when Belloq and Dietrich walk to the car and Belloq shouts "Let's go!", Toht has disappeared. (01:21:45)
Continuity mistake: When Dietrich, Gobler, and Belloq arrive next to the destroyed Flying Wing, Gobler is on the left of Dietrich and Belloq on the right. In the next shot, they have changed places. (01:20:58)
Other mistake: The Angel of Death attacks the altar and Toht and Dietrich scream because of its revelation, but Belloq, for some reason, doesn't seem to see it. Just before the fire column rises, he's still calm. (01:47:10)
Suggested correction: If you don't know the reason, perhaps you should ask a question instead of assuming it is a mistake. Belloq studied the ark and probably better predicted what might come out of the ark. He is also looking directly into the ark and is mesmerized by what he is seeing, until eventually he does scream before his head explodes. The other two are terrified at seeing the apparitions.
Actually, it's pretty impossible that Belloq studied the Ark. If he knew what would come out of it, he literally committed suicide by opening and watching the Ark open, which doesn't make sense. He believed during the whole movie that the Ark contained the Ten Commandments tablets, not some kind of ghastly things.
He didn't know what would come out, but it doesn't mean that he, like Indy, expected just 2 stone tablets. He expected power, for him mostly.
Other mistake: One of the soldiers at the table Sallah and Indy walk next to, is only pretending to eat with his spoon. (00:54:53)
Continuity mistake: In the chapel, before Indy turns the chalkboard over to explain the staff of Ra and the medallion to the G-men, the chalkboard goes back and forth from tilting forward to tilting backward a few times.
