As the night went on, tracking improved as the target moved nearly straight overhead. Guiding was around 0.80 arc seconds RMS toward the end of the run. At first it was around 1.30 which was disappointing. I did tweak the settings in PHD2 which may have helped a little but mostly it is just the better viewing near zenith I think. Around 2 hours total in this stack. I should try a smaller stack of the better frames and see if it gives more detail. Of course I am just using some very basic post processing in Photoshop with help from some actions and AstroFlat Pro so my data could be worked harder.
From the web site messier-objects.com :
Messier 108 (M108), nicknamed the Surfboard Galaxy, is a barred spiral galaxy located in the constellation Ursa Major.
The galaxy lies at an approximate distance of 45.9 million light years from Earth and has an apparent magnitude of 10.7. It has the designation NGC 3556 in the New General Catalogue.
Messier 108 occupies an area of 8.7 by 2.2 arc minutes of apparent sky, corresponding to a spatial diameter of 110,000 light years. The galaxy is inclined 75 degrees to our line of sight. Even though it appears almost edge-on, M108 is a popular target among amateur astronomers and astrophotographers because details of its structure can be seen even in amateur telescopes. The galaxy is easy to find as it lies only 1.5 degrees southeast of the magnitude 2.37 star Merak, Beta Ursae Majoris, one of the Pointer Stars in the Big Dipper . M108 appears in the same wide field of view with the Owl Nebula (M97), which is located only 48 arc minutes southeast of the galaxy. The best time of year to observe M108 is during the spring.