Visible crew/equipment: During Marion and Belloq's beverage contest, a round klieg lamp's blue light stands behind Belloq, which sometimes changes its intensity. Also, when Marion grabs the knife, behind her a moving light can be seen (like a helicopter's light), which disappears a few seconds later. This light also appears for a few seconds when Toht frees Marion's arm.
Continuity mistake: After the kliegs behind Dietrich, Belloq, and Toht explode, the Ark's energy begins to destroy the soldiers' guns and the kliegs next to them. In some shots, the kliegs on the altar are still working.
Continuity mistake: Just before Belloq says "It's beautiful!", there is a black machine (which is not the German camera or the generator) in the bottom middle of the screen, just below the approaching ghost. It is also visible when the Angel of Death is revealed. This machine disappears when the Ark begins to kill the soldiers.
Continuity mistake: When Dietrich and Toht look at the ghosts that pass behind them, the column of mist that is coming out of the Ark disappears.
Visible crew/equipment: Just as Indy and Sallah walk near the table with the soldiers eating, on the dune in the background (near the Map Room), four crew members (not wearing German uniforms or Arabian tunics, but shirts and jeans) can be seen sitting, watching the scene. (00:54:46)
Visible crew/equipment: Right when the Nazis are struck with the light, one soldier shakes wildly and one can see the cable coming out of his trousers and stretching off-screen to the right. (01:47:30)
Continuity mistake: When Indiana is confronted by the Cairo swordsman, he already has his left shoulder pointing towards his opponent in the shot where the crowd scatters. But in the following shot, where the swordsman is first seen, Indiana has his right shoulder pointing forward and is just turning around to his left side. (00:40:14)
Continuity mistake: The amount of moss behind the idol increases between shots.
Answer: Indy and Marcus Brody believed that the Ark needed to be studied. They certainly didn't want to put it back where it was found. They believed that the U.S. government would find the best archaeologists, researchers, and scientists in the world to study the Ark. They are both upset that instead, the government has decided to simply lock the Ark away. This is why Indy says, "Fools. They don't know what they've got there," as he is leaving the building.
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