NGC 3981, Unbarred Spiral Galaxy

NGC 3981 is an unbarred spiral galaxy. It is located in the constellation Crater. It is 65 MLY distant. NGC 3981 is part of the Virgo Supercluster of galaxies. The irregular, outstretched shape of its arms is likely due to a gravitational influence from an encounter with one of its galactic neighbors. (NSF, NOIR Lab)

Image processed by Andrew Macica, original data from Telescope Live.

Imaging Details:

Observatory: El Sauce Observatory

Location: Rio Hurtado Valley, Coquimbo Region, Chile

Telescope: ASA 1000, a 1-m telescope

with a Ritchey Chretien design

Aperture: 1000 mm (39 inches), f/6.8

Focal Length: 6800 mm

Camera: FLI ProLine PL16803 CCD

Filters: LRGB

Total Exposure: 32 hours 40 min.

Image Processing: PixInsight 1.8.9-3 Ripley (x64);

BlurXTerminator, NoiseXTerminator (RC Astro);

Adobe Photoshop 12.5.1;

Adobe Lightroom Classic 14.1.1

Instruction on PixInsight from Adam Block Studios.

The 1 Meter telescope is an excellent telescope and I always wanted to image through a 1 Meter telescope. On the other hand every telescope, no matter how good it is, comes with challenges and the ASA 1000 is no different. It has an Alt/Azimuth mount and uses a camera rotator to prevent streaking. As a result, the data I downloaded had artifacts I needed to deal with. Initially I did not think I could resolve the issues, but after careful thought, I came up with some solutions.

This turned out to be an interesting experience. Even though I have a subscription to Adam Block Studios, I was unaware of a tutorial on the NGC 3981 data from Telescope Live.

The image above was produced using a combination of Adam Blocks tutorial and also using much of the original technique I used to process the original image.