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alocky
18-04-2018, 12:56 AM
Just in case there was another supernova in it, I gave it 12 hours over two nights.
One of the most beautiful spirals in the sky. 15 million light years away, and if you zoom in on the full resolution image (cropped and rotated slightly differently to the thumbnail) you can even see the weird lumpiness around the nucleus.
https://www.astrobin.com/full/342075/0/
cheers!
Andrew.

Peter Ward
18-04-2018, 09:58 AM
Wow! ..a very slick rendition indeed. Uber tight stars and great colour.
A top shelf image for sure :thumbsup:

RickS
18-04-2018, 11:10 AM
Fantastic scale & detail, Andrew!

Placidus
18-04-2018, 11:47 AM
Andrew, that is a magnificent image. We particularly like the way you have preserved detail in the innermost bright core.

It is instructive to compare the core region and immediate surrounds in your image with the 6 megabyte version of the Hubble (http://hubblesite.org/image/3293/news_release/2014-04) shot. Your basic structure is spot-on, whereas most folk just show a brilliant shapeless blob. All of us face a risk of converting nebulosity into nonexistent stars when deconvolving or wavelet sharpening, and you have a quite few in there, but for a millionth of the budget, your image of the core is quite the best we've seen.

Best,
MnT

strongmanmike
18-04-2018, 01:02 PM
Yeah looks good Andrew, the colour is nice and at normal size view it looks quite detailed, well done. Some minor feedback and along the lines of the poster on AB and what M&T have said, the stars could be fixed so that they don't have a sharp bright centre and I suspect what ever has caused this (deco/wavelets etc?) has created some dottyness within the galaxy details too..?

Otherwise, a fine M83 :thumbsup:

Mike

gregbradley
18-04-2018, 07:31 PM
That's an excellent M83 Andrew. You are really showing how extensive the outer halo is here.

Greg.

h0ughy
18-04-2018, 08:46 PM
really nice, eye catching

alpal
18-04-2018, 09:18 PM
Hi Andrew,
that's an excellent picture.
The ASA 16 & the DDM85 mount are giving great results.
The stars do have some strrange dots in the middle of them
but that's just a processing problem -
the data is fine.

cheers
Allan

billdan
19-04-2018, 12:15 AM
Great job Andrew, one of my favourite galaxies.

Geoff45
19-04-2018, 06:08 AM
Hard to improve on that one Andrew. Well done.

clive milne
19-04-2018, 08:07 AM
Oooh, that's lovely that is...

Well done.



Still a lot of moisture in the air so the transparency is a bit average.

Waiting for Autumn to arrive... if memory serves me correctly, the coldest day since the end of the monsoon season has been 37C.

Nice to have 18 degrees more elevation of all the Northern sky, however.

btw) How's Barry going with his latest Windmill? Should be almost ready for first light I imagine?

best
~c

Jeff
19-04-2018, 10:28 PM
Lovely Andrew.
Have bookmarked that one!

alocky
22-04-2018, 02:40 PM
Thanks everyone for your kind words, I certainly got a surprise when I started looking through the subs and realised how much detail was in there. There are some funny issues in the stars, and I'm backing out a few of the steps to try and improve them.

alocky
22-04-2018, 02:44 PM
Thanks to Mike and Mike and Trish for making some really constructive suggestions. The decon was very mild, and the culprit seems to be the HDR transform that compresses the top end of the dynamic range. This is the step that brought out all the detail in the nucleus, but seems to have made the cores of the stars very hard as well. It also seems to have 'asterised' some of the detail in the blue parts of the arms as Mike and Trish noted - more so than the decon.
I'll have to get into the world of star masks to solve one problem without removing the other.
cheers,
Andrew.

Paul Haese
23-04-2018, 06:17 PM
The detail is superbly sharp Andrew. One of the sharpest versions I have seen here. Colour is a bit muted and the back ground appears a little blue to me, but the detail more than makes up for it. You must have got your v curves near spot on and the seeing was with you on those two nights.:thumbsup: