NGC 6946 - The Fireworks Galaxy - OSC Version
Date: September 23, 2020
Cosgrove’s Cosmos Catalog ➤#0053
NGC 6946 as captured by my William Optics 132mm Platform. (click image for full resolution via Astrobin.com)
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About the Target
NGC6946 - The OSC Camera Version, Known as the Fireworks Galaxy and Caldwell 12, is a face-on spiral galaxy on the boundary between Cepheus and Cygnus' constellations. It is located 25.2 Million Light years away and is about 1/3 of our own Milkyway Galaxy size.
I first took a shot of this galaxy in 2019, and I was delighted with the result! It was one of my first galaxy images, and I could actually see the arms of the galaxy!
The Annotated Image
An annotated image of NGC 6946 was created using Pixinsight’s ImageSolver and AnnotateImage Scripts.
The Location in the Sky
About the Project
During the past few nights, I revisited this target, and I shot it with two telescopes simultaneously. In one (this one), I used a One-Shot-Color Camera, and in the other, I used a Mono camera with L, R, G,&B filters. I wanted to see the difference I would get with both approaches.
There always seems to be a big debate about the merits of the OSC vs. the Mono camera, and I thought these images would showcase the differences.
The OSC version resulted from 130 frames of 150 sec for a total exposure of about 5.5 hours. The mono version had about the same level of exposure.
As it turns out, I had a parameter set wrong, and the images ended up being rotated 90 degrees from one another. Despite that, please take a look at both of them and tell me which one you like better.
The OSC version of the image. (click to zoom)
The Mono- LRGB version of the image. (click to zoom)
Updated Comments 7-26-21 (as I publish this into the website):
The two resulting images from this test are very similar and one conclusion that can be made is that you can get about the same results on both systems. Having said that, I find that I prefer the Mono version image a bit more - the galaxy arms seem to have a better definition and more of a 3D form to me. Most others that have weighted in here would tend to agree. In the end, I think it is a preference call. Having said that, you are also looking at some other differences in these images which is likely impacting your preference. The Mono image has a slightly larger image scale and the background sky was made darker in this image. These factors may well have had a larger impact on your preference than whether it was OSC vs Mono.
2019 version of NGC 6946 (Click to zoom)
My very first effort on NGC 4564 was done in September of 2019.
You can see that post HERE.
This was very early on and I include it for comparison. I am pretty happy with the improvements shown there!
Capture Hardware
Scope: William Optics 132mm FLT F/7 APO
Guide Scope: Apterna 60mm
Camera: ZWO ASI294MC-Pro
Guide Camera: ZWO ASI290Mini
Focus Motor: Pegasus Astro Focus Cube 2
Field Rotator: Pegasus Astro Falcon
Mount: Ioptron CEM60
Polar Alignment: Ioptron Ipolar integrated alignment cameras
Software
Capture Software: PHD2 Guider, Sequence Generator Pro controller
Image Processing: Deepsky Stacker, Pixinsight, Photoshop, Coffee, extensive processing indecision and second-guessing, and much swearing…..
During the Summer of 2020, whilst stuck at home because of Covid I became very in improving the automation of the platform and achieving a more precise framing of the shots I made…