NGC 7331 et al. (Peg)

NGC 7331 et al. (Peg)

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Date/Site: 13. October and 13. November 2020, remote observatory on the AAR club's site in Presberg
Exposure/
Filter:
R: 34 x 180 seconds,
G: 30 x 180 seconds,
B: 29 x 180 seconds,
L: 33 x 180 seconds (-20°C)
Camera: Moravian G3-16200 with Astronomik Type II-filters
Optics/
Instrument:
250mm f/4,7 Newton with VIP-3010 Paracorr on 10Micron GM1000 HPS
Guiding: Lodestar attached to a 61mm-finder,
focusing: Microtouch and FocusMax,
data acquired remotely using CCD-Commander and MaximDL 5,
calibration and processing: PixInsight 1.8

With the new configuration my favourite galaxy-group had to be imaged as well.
The background of the image is a bit flaky and blotchy; some of it sure is real signal from the Integrated Flux Nebula (IFN) in this area. On the other hand some spots seem to be processing artefacts. Therefore an image with a controlled darker background is presented here.
Half a degree southwest of NGC 7331 lies the compact galaxy-group "Stephan's Quintett" containing NGC 7318 and 7320, which I imaged close up not so long ago.
 
And some earlier attempts at this object:

NGC 7331 et al. (Peg)

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Date/Site: 5. September 2018, remote observatory on the AAR club's site in Presberg
Exposure/
Filter:
R: 9 x 300 seconds,
G: 13 x 300 seconds,
B: 15 x 300 seconds (-20°C)
Camera: QSI 632 with Astronomik Type II-Filters
Optics/
Instrument:
250mm f/4 Newton with Baader RCC1 on 10Micron GM1000 HPS
Guiding: Lodestar attached to a 61mm-finder,
focusing with Microtouch and FocusMax,
data acquired remotely using CCD-Commander and MaximDL 6,
calibration: MaximDL 6, processing: PixInsight 1.8

Every now and then I come back to this wonderful group of galaxies.
 

NGC 7331 (Peg)

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Date/Site: August 16., 2009, AAR-observatory in Presberg
Exposure/
Filter:
L: 6 x 6, R: 6 x 6, G: 7 x 6, B: 7 x 6 minutes (-12°C)
Camera: SBIG ST10XME, motorized Atik-filterwheel with Astronomik-RGB-filters
Optics/
Instrument:
13"-Newton on the Gemini 41 Observatory mount, Baader coma-corrector
focusing with RoboFocus and MaximDL,;
deblooming, flats, darks, alignment and stacking: MaximDL,
levels and curves: Photoshop CS

In a warm midsummer-night in August 2009 a last attempt for a LRGB with the 13" was made. So this probably is the last image with the 13", because without reworking the mirror seriously there seems to be no way to get really good results with it.
In the beginning the headlights of the farmer plowing the adjacent field in the middle of the night interfered and in the end the break of dawn ruined the last image.
And this was the first test of the same object with the 26cm-Newton:

NGC 7331 (Peg)

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Date/Site: October 26., 2009, Presberg
Exposure/
Filter:
Luminance 3 x 5 minutes (-20°C)
Camera: SBIG ST10XME
Optics/
Instrument:
26cm-Newton on Gemini 41 Observatory mount, 1.6 x Barlow (f8)
focusing by hand,
darks, alignment and stacking: MaximDL 4.6.
levels and curves: Photoshop CS

 

NGC 7331 et al. (Peg)

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Date/Site: August 31., 2008, AAR-observatory in Presberg
Exposure/
Filter:
L: 6 x 10 minutes
RGB: 3 x 5 minutes, 2x2 Binning (-15°)
Camera: SBIG ST10XME, motorized Atik-filterwheel with Astronomik-RGB-filters
Optics/
Instrument:
6"-Newton on the Gemini 41 Observatory mount, Baader coma-corrector
focusing by hand with the aid of MaximDL 4.6
Deblooming, darks, alignment and stacking: MaximDL,
levels and curves: Photoshop CS

Remarks: first LRGB with the new ST10; the reflector wasn't properly collimated, I promise to take care next time.

© Friedhelm Hübner, last revision:  17.01.2021