For Full Resolution View (2600 x 1773) click HERE.
M63 - Sunflower Galaxy
Click on Image to switch to Annotated View.
A bright spiral galaxy of the northern sky, Messier 63 is about 25 million light-years distant in the loyal constellation Canes Venatici. Also cataloged as NGC 5055, the majestic island universe is nearly 100,000 light-years across. That's about the size of our own Milky Way Galaxy.
Known by the popular moniker, The Sunflower Galaxy, M63 sports a bright yellowish core in this sharp, colorful galaxy portrait. Its sweeping blue spiral arms are streaked with cosmic dust lanes and dotted with pink star forming regions. A dominant member of a known galaxy group, M63 has faint, extended features that could be the result of gravitational interactions with nearby galaxies. In fact, M63 shines across the electromagnetic spectrum and is thought to have undergone bursts of intense star formation.
After the fiasco with M33 and CCDT67 reducer at 0.67x reduction with GSO 8" RC I have placed the reducer as close as possible to the sensor. I simply threaded it to the TSOAG9 which is connected with EOS adapter to the camera. That gave me the reduction of 0.72x and scope were operating at 1165mm at f5.76. That partly solved the corner problems but still, no 100% real estate. Since I can't move it closer than that, I have to leave with that and crop. That doesn't bother me much especially when imaging small objects like M63 were I'm going to crop it anyway.
I always pay attention to the lenght of my exposure to asure me with 90% stacking efficiency, but this time, for the sake of my curiosity I went with lower ISO and shorter exposures. 10 minutes at ISO800 at f5.76 and my black desert skies produced histogram of just 13% from the left, just enough to separate all three channels. That would be on the border of 70% and 80% stacking efficiency. First who suffer from that is the PGC46093, the small cloud to the right of the galaxy, as it just surfaced the background noise. Second, is the much larger faint halo surrounding the galaxy, which all went to the noise and could't be pulled out, although visible with very aggressive stretching.
With that said, I'm just lucky to have a very dark site, an object this bright and providing good amount of data, almost 7 hours in this case, I was able to achieve the result you are seeing, without applying aggressive processing, which I'm not fond of.
All hails go to Ken and Jared, writers of the Sequence Generator Pro! That was my first night with it and I simply stunned by the power of that package. Very smart and sophisticated piece of software. I had to spend some time with it adjusting the parameters of Autofocus, which is problematic with secondary obstruction and DSLR bayer, but SGP now provides software binning and that solved my problems and Autofocus run at least 3 times during the night and kept me in focus while I was napping. It perfectly performed Auto Meridian flip, plate solving works just in seconds, precise centering on target, dithering and control over PHD2 were running all automatically without my interaction. I did found my self spending more time by looking up at the stars.
Optics : GSO 8" RC + CCDT67 @ F5.76 @ 1165 mm
Camera : Canon T3i (600D) Baader Mod
Mount : NEQ-6 Pro (Self Hypertuned/Belt Mod)
Guiding: Telescope Service OAG9 + SX Lodestar
Acquisition : Sequence Generator Pro (18.104.22.168)
Exposure : 40 x 600 sec @ ISO800 - 6 Hours 36 minutes
Stacking : PixInsight 1.8 (1123)
Processing : PixInsight 1.8 (1123)