I was just looking for a target in the dark area of my sky for the short time between dusk and moon rise. I cam across this region searching in Stellarium, and was surprised it had no common designation. Captured around 1.5 hr of data to produce this image from the depths of the milky way, A myriad of colorful stars stand out from the thousands in this image. Astrometry found 4686 stars to work with identifying the center position as:
RA 19hr 59m 48sec
Dec +35deg 24m 46sec
The brightest star is the crook of the neck of Cygnus designated “n” or the abreviated “n Cyg”. It can also be described as the southern star of the “northern cross” which makes the body of the Swan. At the northern end of the cross is the better known star, Deneb. The Crescent Nebula lies just north of this region.
The Iris Nebula is a reflection nebula in the constellation Cepheus that I was able to image on the 24th. The moon was bright so I was looking for targets in the North East for the darkest skies. I got 22 subs at 240 seconds with ISO 800 but the tracking was only fair. Transparency was not the best and a bit of breeze caused some shifting I think. That and or “chasing seeing” where the guide scope image is wavering around. It still just amazes me what can be pulled from the data I start with. Never give up on washed out subs!
I need to try adding a little more distance to my Coma Corrector as it still shows under-correction toward the corners, but some of that is tracking. Some images I adjust a bit using the lens distort effect in Photoshop but not on this one. You can tell because it will distort the angle of the diffraction spikes across the field when software corrected.
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.
The Crab Nebula from the night before. Supernova remnant 6500 light years away. Image collection was cut short when some clouds moved through but my post processing is improving I think, so at least I got something for the effort.
The Wizard Nebula from two nights ago. Better imaging than the last few nights after adjusting: mirror collimation, polar alignment of the mount, camera focus and attachment. Decent tracking with almost no wind as well helps. Over an hour of data on this one.