The showcase galaxy in this image is NGC 7331 or Caldwell 30. It is a large unbarred spiral galaxy approximately 40 million light-years away in the constellation Pegasus. Four other galaxies, NGC 7335, 7336, 7337, and 7340 along with NGC 7331 make up what is known as the NGC 7331 Galaxy Group, however, these other galaxies are not interacting with NGC 7331 as they are much more distant at 300-350 million LY away. Its size is similar to the Milky Way but it is not considered to be a true twin since it is unbarred unlike the Milky Way. Also interesting is that the central bulge rotates in the opposite direction as the rest of the disk.
I have imaged this in the past with my smaller AT115 refractor and this is a much better version as I was able to get more detail. There are much better versions of this out there and I was hoping this would be better but given my equipment and conditions this is it. It turned out to be a processing marathon mainly due to the stars. It is well known the SCT stars, all things being equal, are not as good as refractor stars and if something is not quite right the issue is magnified. A couple of nights the seeing and transparency were subpar and focusing was fair at best. I believe the collimation is good but I am not convinced my corrector plate is perfectly aligned with the primary mirror as my stars have never been really good. In addition, I cropped this down about two-thirds so the stars were highly bloated and misshapen. I did my normal star reduction but did not want to do any more since it removes stars altogether.
I tried fixing them using various methods PI and PS that I found on the web but none of them worked so this led to me inventing a new method. In a nutshell I did the following:
1) used the 'Select Bright Stars' from the Astronomy Tools PS Plugin and then expanded the pixels to 2 and feathered it by 2 (these were round).
2) copied the stars as a layer to a starless version (made in PixInsight).
3) merged this new version with the original version and then carefully erased the 'bad' stars which were replaced by the new 'good' stars.
-This method is very tedious and time-consuming and is probably considered cheating but it worked.
I have imaged this in the past with my smaller AT115 refractor and this is a much better version as I was able to get more detail. There are much better versions of this out there and I was hoping this would be better but given my equipment and conditions this is it. It turned out to be a processing marathon mainly due to the stars. It is well known the SCT stars, all things being equal, are not as good as refractor stars and if something is not quite right the issue is magnified. A couple of nights the seeing and transparency were subpar and focusing was fair at best. I believe the collimation is good but I am not convinced my corrector plate is perfectly aligned with the primary mirror as my stars have never been really good. In addition, I cropped this down about two-thirds so the stars were highly bloated and misshapen. I did my normal star reduction but did not want to do any more since it removes stars altogether.
I tried fixing them using various methods PI and PS that I found on the web but none of them worked so this led to me inventing a new method. In a nutshell I did the following:
1) used the 'Select Bright Stars' from the Astronomy Tools PS Plugin and then expanded the pixels to 2 and feathered it by 2 (these were round).
2) copied the stars as a layer to a starless version (made in PixInsight).
3) merged this new version with the original version and then carefully erased the 'bad' stars which were replaced by the new 'good' stars.
-This method is very tedious and time-consuming and is probably considered cheating but it worked.
https://www.instagram.com/astroquest1/
http://astroquest1.blogspot.com/
https://www.astrobin.com/users/kurtzepp/collections/
http://youtube.com/c/AstroQuest1
NGC 7331 & NGC 7331 Galaxy Group (2022)
Dates: 10-27, 10-29, 11-1
Camera: ZWO ASI294MC-Pro
Telescope: Celestron EdgeHD 800
Barlow: None
Focal Length: 2032mm (native), 1400mm
F/10 (native), F/7
Focal Reducer: Celestron 0.7 Reducer Lens
Mount: Orion Atlas Pro
Filter Adaptor: ZWO Filter Drawer
Filter: Baader UV-IR
Focuser: ZWO EAF
Autoguiding: ASI120 Mini attached to an Orion ST80
Exposure: Baader UV-IR 292 x 90
Gain: 139
Offset 0
Temp: -10 C
Processing: Asiair app, PixInsight, Photoshop, StarXTerminator, Topaz DeNoiseAI, NoiseXTerminator.
http://astroquest1.blogspot.com/
https://www.astrobin.com/users/kurtzepp/collections/
http://youtube.com/c/AstroQuest1
Dates: 10-27, 10-29, 11-1
Camera: ZWO ASI294MC-Pro
Telescope: Celestron EdgeHD 800
Barlow: None
Focal Length: 2032mm (native), 1400mm
F/10 (native), F/7
Focal Reducer: Celestron 0.7 Reducer Lens
Mount: Orion Atlas Pro
Filter Adaptor: ZWO Filter Drawer
Filter: Baader UV-IR
Focuser: ZWO EAF
Autoguiding: ASI120 Mini attached to an Orion ST80
Exposure: Baader UV-IR 292 x 90
Gain: 139
Offset 0
Temp: -10 C
Processing: Asiair app, PixInsight, Photoshop, StarXTerminator, Topaz DeNoiseAI, NoiseXTerminator.
https://www.instagram.com/astroquest1/
http://astroquest1.blogspot.com/
https://www.astrobin.com/users/kurtzepp/collections/
http://youtube.com/c/AstroQuest1
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