M31 more commonly called the "Andromeda Galaxy" is maybe the most observed and photographed deepsky object. Like an alpinist, who has to climb once in his/her life the Matterhorn, an astrophotographer has to shoot at least once in his/her life Andromeda. Yet, as for the alpinist, Matterhorn should not be your first, and from my perspective this holds true also for M31. As a matter of fact, despite the large size and huge brightness, this fantastic galaxy has several challenges. The first is the strong light difference between the center and the arms, the second is the presence of beautiful but small and weakly emitting nebulas, the third is linked to the resolution, where only with reasonable resolution one can really appreciate the extreme complexity, as well as the stars within Andromeda. About the latter, I was suprised to see that, even recently rewarded images on Astrobin suffered from some inconsistencies, such as the absence of the "blue stars" on the external arms. Indeed, to highlight the very faint regions of the external arms, it is now usual practice to generate a starless version of M31, and then add back the stars by lowering their intensity and contrast. However, one has to be extremely careful in adding back the stars of the galaxy as well, otherwise these will be irremediably lost. It is what happened to a number of images I saw.
This version is no more, no less a very classical LRGB composition with the addition of the Ha layer to enable the detection of the nebulas. The Ha layer is definitively a bit weak, thus I am sure that the weak nebulas were lost during the final assembly.
Conversely, I tried to be as accurate as possible on the light balance, the color saturation and the galaxy details, including the stars.
I hope that this new version reflects a reasonably faithfull interpretation of one among the most beautiful deepsky objects of our sky.
Don't hesitate to feedback me your thoughts