A fairly deep M83 in monochrome. (We have a ways to go to match Paul Haese's 23 hour image).
Not going to get colour on this before next new moon, and we're too keen to leave it in the cupboard till then.
Total exposure 13.5 hrs. 6.5 hours in half hour subs this new moon, plus 7 hours in 1 hour subs from 2016.
Big one here
In processing we had four goals:
- To preserve the detail close in to the galactic nucleus, without burning it out (only partially successful).
- To show the extensive faint halo (success)
- To show detail, including the intriguing and extremely faint outer ring around the inner of the two tiny galaxies close in at about 1 o'clock.
- To show as many other distant galaxies as possible. Although mostly tiny, their number is beyond counting. Sobering to think that each has say 200,000,000,000 stars.
We've not gone for a super-contrasty look in the mid-zones, which would have either changed the overall look of the galaxy or defeated the other goals.
An added surprise was what we guess will prove to be a quite detailed strand of star formation at the tip of the very faint spiral arm at two o'clock. The strand is oriented in an 11 o'clock 5 o'clock direction and is very thin. This strand seems concave away from the main galaxy. It is visible in Paul's Haese's 2016 image, but has come out very nicely here.
Paul mentioned that there appears to be a dark ring around the galaxy, which did not appear attributable to flats or processing. We see the same thing, and do not believe it is due to flats or processing either.
Also of some comfort was that the 2018 image and the 2016 image looked virtually identical, and the equipment is not degrading with time*.
Aspen CG16M on 20 inch PlaneWave on MI750 fork. As usual, scope, focus, and dome motors controlled using electronics built by us. Observatory firmware and software, and image processing software all written by MBJ.
Very best,
Mike and Trish
* Unlike our ride-on mower's hydraulics and Mike's elbows.