18 Apr 2013

Abell 61

I imaged this small planetary nebula, also known as PNG 077.6+14.7, in early April. Processing took several days and versions before I was happy enough.

Abell 61 is about 3.4' in diameter and mostly round. It's located in constellation Cygnus. Abell (1966) described it as "incomplete rings with gaps". The central (mag 17) variable star is WD1917+461. Its distance is unknown.

And here's 100% crop of the nebula.

Exposure details:
                             Ha            5 * 1800"
                            OIII           7 * 1800"
                             TOTAL    6h

Full size again in Astrobin

15 Apr 2013

NGC2685 reprocessed

As I said I wasn't too happy with the star colors of the first post so here's new version of this polar ring galaxy.

9 Apr 2013

PK164+31.1 continued

After all I came back to this target with one night and get some more luminance for it. Here's extra 3h 40min of it with now a total exposure of 12hrs.

Full size again on Astrobin

M51, The Whirlpool Galaxy

I took few images during near full moon (90+ percent) of this famous galaxy. I didn't had any big expectations of the result because of the moon phase and short exposure time. But the final image surprised me!

Here's only 2h 50min of exposure:
                                             L        =   4 * 1200"
                                             RG     =   3 * 300"
                                             B        =   6 * 300"
                                             Ha      =   3 * 600"

8 Apr 2013

Draco trio reprocessed

I've done some reprocessing of the picture to bring out more of the ngc5982's (elliptical galaxy) outer parts.

I used J-P Metsävainio's (http://astroanarchy.blogspot.fi/) brilliant tonemapping method. I've never used it before to LRGB-imaging but it seems to work perfectly.

Here's a "boosted" version of the Draco trio:

5 Apr 2013

Draco Trio; NGC5981, NGC5982 and NGC5985

This is a fascinating view of three totally different galaxies. From top to bottom there's a face-on spiral NGC5985, an elliptical NGC5982 and a edge-on NGC5981. And in the background there's dozens of faint galaxies.

While the group is far too small to be a galaxy cluster and has not been cataloged compact group, these galaxies all do lie roughly 100 million light-years from planet Earth. On close examination with spectrographs, the bright core of the striking face-on spiral NGC 5985 shows prominent emission in specific wavelengths of light, prompting astronomers to classify it as a Seyfert, a type of active galaxy.

NGC5985 has a size of 3*5.5 arcmin (mag 11.1), NGC5982 has a size of 2.6*1.9 arcmin (mag 11) and NGC5981 has a size of 0.3*2.8 arcmin (mag 13.89).

Exposure of this image is:
                                      L              =  14*1200"
                                      RGB         =    8*300" (bin2*2)
                                      TOTAL    = 6h 40min

Full size again on Astrobin