The Moon hoaxers, often called HBs (Hoax Believers), claim that either the star locations would be substantially different (i.e. different constellations) or that they would be substantially brighter. Neither is true; people have computed the actual loss due to the atmosphere and it's pretty small, except at the horizon.
The "substantially brighter" argument is often used as a prop for the claim that the stars should have been visible in photos taken on the surface, or that the astronauts should have easily seen the stars.
The "twinkling" effect is about the only significant difference, and that's not visible in still photos.