There has been some further processing after stacking to neutralise the brown background.
You can now begin to see (in the inset) that the galaxy has a shape similar to a fried egg. There is a bright central bulge and the outer disc fades away. We are viewing it obliquely. We will see a better view later.
The huge number of stars makes it difficult to pick out any constellations, so we will mark some on the next slide...