The upper is a large FOV images take with the FSQ telescope and the QHY90A CCD on August 10th, 2016. It is a stack of 9 Ha frames of 1800s of exposition each. Total time 4hr 30min.
The lower is again a Ha image but with a much more narrow FOV (about one fourth of the previous image) and is the result of 31 Ha frames 900 s long, for a total exposition time of 7 hr 45m. The frames were taken on August 2016.
The North America Nebula (NGC 7000 or Caldwell 20) is an emission nebula in the constellation Cygnus, close to Deneb (the tail of the swan and its brightest star). The remarkable shape of the nebula resembles that of the continent of North America, complete with a prominent Gulf of Mexico. Therefore is sometimes called the “North American Nebula” nickname (see the top image above).
The North America Nebula is large, covering an area of more than four times the size of the full moon; but its surface brightness is low, so normally it cannot be seen with the unaided eye.
The portion of the nebula resembling Mexico and Central America is known as the Cygnus Wall. This region exhibits the most concentrated star formation as seen in the second image above.