Processing in Deep Sky Stacker, Pixinsight, Photoshop

Sharpless 129 is an H-alpha emission nebula commonly called the Flying Bat Nebula located in Cepheus very close to the famous IC 1396 (the nebula that contains the Elephant's Trunk). The large blue/green nebula inside it, which is over a degree long, is formally known as Ou4 but is colloquially called the Squid (or Giant Squid) Nebula. Ou4 is remarkable for having been discovered very recently, in 2011, by amateur astronomer Nicolas Outters (hence the "Ou" in "Ou4"). It was originally called a planetary nebula but is now thought to be some kind of bipolar outflow from the bright blue star at its center (which is HR 8119).

Both Sharpless 129 and Ou4 take up a lot of sky so a large field of view is necessary to capture them.