So there is this huge picture by Hubble.
Better yet, with the zoom tool
And if you zoom to the maximum level, you can see a seemingly uniformly distributed dots of orange and blue. Are those actually stars and maybe galaxies behind them and not just camera noise?
Furthermore I'm trying to get a grasp on how large portion of the sky this photo represents.
At 3.4, the apparent magnitude of the Andromeda Galaxy is one of the brightest of any Messier objects, making it visible to the naked eye on moonless nights even when viewed from areas with moderate light pollution. Although it appears more than six times as wide as the full Moon when photographed through a larger telescope, only the brighter central region is visible to the naked eye or when viewed using binoculars or a small telescope.
Let's say this is about the half of the diameter of the galaxy so this photo is about ~3 Moons wide, is that correct?