I hope no one gets mad, but to me this is the most obvious slip-up in the film.

When Harrison Ford is down in the well of souls, being addressed by his colleague looking down through the opening, the sky alternates between:

- dreary and overcast

- sunny cloudless bright blue

- nearly stormy

several times in a few seconds.

This cold mean they changed the script after production started and didn't bother to re-shoot all of a few simple lines.