Canon XSi, modded, Total RGB 39 min. = 13x3 min, ISO 1600
Baader MPCC, LXD75-SN10 OTA, EQ6 mount, guided w/PHD and EQMOD

Spiral Galaxy NGC 6946 and Open Cluster NGC 6939 are located about 2 degrees southwest of Eta Cepheus.

NGC 6946 is a 9.7 magnitude spiral galaxy that was discovered by William Herschel on September 9, 1798 and is about 10 arc minutes in diameter.

It is a relatively close galaxy at a distance of about 10 million light years, and was once suspected by Edwin Hubble of being a member of the Local Group of galaxies that includes the Milky Way, but today it is not believed to be a member. Because we are looking at it through the plane of our own galaxy, it is highly obscured by dust.

NGC 6946 is sometimes called the Fireworks Galaxy because of the number of supernovae that have been discovered there and the galaxy's prodigious rate of star formation.

By contrast, open cluster NGC 6939, seen about 40 arc minutes northwest of NGC 6946, is located inside of our own galaxy at a distance of approximately 5,800 light years. It is just by coincidence that these two objects lie close to each other in the same line of sight.

NGC 6939's total brightness is about 8th magnitude and it contains about 80 stars in its 8 arc-minute diameter and its brightest member is about 12th magnitude.

I have copied this text from Jerry Lodriguss excellent summary: http://www.astropix.com/HTML/SHOW_DIG/053.HTM