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View Full Version here: : First image VC200L Astrofest - Corona Australis


allan gould
03-08-2011, 02:06 PM
I wanted to keep this years Astrofest to the lowest imaging/frustration level so I took the QHY8 OSC with my new 2nd hand VC200L and 6.4Flattener/reducer on the EQ6 mount.
The first image with this setup was Corona Australia Nebula with the globular NGC6723. The combination of the dust, reflection nebula and the globular are a favourite of mine.
This was a stack of 48x5min exposures at f6.4.
Comments welcomed

Gem
03-08-2011, 02:14 PM
Nice! Good choice of object too. :)

Gem
03-08-2011, 02:20 PM
NGC 6723 is actually SGR... the image crosses over two constellations! :)

gregbradley
03-08-2011, 03:40 PM
A very nice image. I like it. Lots of detail in the blue areas and sharp.
The only thing that takes my attention is the glob seems a little dull.

Perhaps a lasso, feather and a bit of curves to boost it in Photoshop?

A bit hard to tell with the image but are the stars on the left on average larger in the image than
the ones on the right? Perhaps some tilt in your camera/focuser.

Greg.

jase
03-08-2011, 04:03 PM
Excellent work Allan. Has a crisp feel to it as though it snap focus sharp. My only negative critque is on the processing and probably what Greg picked up on. The glob looks flat as I think the data could be stretched more, in addition you've slightly black clipped the red and green channels. While this has boosted the blue reflection nebulosity, it hasn't done much to aid in balancing other aspects of the image. Would be worth seeing what more information you could extract from this data set. It should deliver a fantastic result.

jjjnettie
03-08-2011, 04:52 PM
I LOVE that you didn't burn out that glob. A beautiful image.
So you were actually doing some imaging in your tent as well?

Lester
03-08-2011, 04:57 PM
Very nice image Allan, and being your first with this set-up, the potential is very good.

troypiggo
03-08-2011, 07:09 PM
Beautiful region, that. If I hadn't had all my equipment woes, I'd have given it a go too.

Paul Haese
03-08-2011, 07:12 PM
Allan, nice to see you have a go at this. I like the framing which includes the globular. I think this would look better in portrait though.

The image looks just a little flat and I think you could boost the look overall with either shadows and highlights or curves or a bit of both.

allan gould
03-08-2011, 07:17 PM
Greg and Jase
Thanks for the kind comments and in relation to the Red and Green clipping and the globular, I did a re-process on the image and I feel that it is now better. Id originally toned down the globular as I felt it was distracting but then realised, Why photograph it in frame if I didnt really want it there?
Greg, in relation to the stars being tighter on the right of the frame I really feel that its due to the dust extinction on the stars making them appear smaller on the right of the frame.
Thans for the comments as its really appreciated and Ive included a reprocessed image.

allan gould
03-08-2011, 07:21 PM
Thanks JJ and glad you liked it - remember what goes on in the field stays on the field

Getting to like this new scope and what it can do.

Yeah sure, sure. If it hadn't been for that bottle of wine and the 1/2 dozen beers you may have known where you were and what to do :D


Thanks Paul - hope you like the repro.
Allan

jjjnettie
03-08-2011, 07:45 PM
The repro is top shelf Allan.

The photos of what happened on the field stays on my laptop.....for now. :wink2:

jase
03-08-2011, 08:19 PM
Great repro Allan. The glob now pops nicely. Well done.

desler
03-08-2011, 08:44 PM
I really like it Allan, great job. Glad to see it all worked well for you!

Darren

allan gould
03-08-2011, 11:29 PM
Im waiting.

Thanks for the tips Jase


Glad you liked it Darren

jjjnettie
04-08-2011, 01:25 AM
I'll stand by the code Allan.
I had enough embarrassment at Astrofest when I sobered up and realised what we'd done. :eyepop:

Paul Haese
04-08-2011, 11:00 AM
The repro is better and the glob looks better, but I think the main nebula is still lacking. Perhaps sub lengths are the culprit here.

Paul Haese
04-08-2011, 11:16 AM
I hope you don't mind Allan but I did a bit of work to the image. I don't normally repro other peoples work, but thought this would be instructive for you (not that I am any expert). I think this version looks a little better and less flat. I will explain and just show you what I did.

First I did a shadows and highlights around 33%. Then I did a curves adjustment with the medium setting which I boosted on the right hand side. Small amounts are only needed here, large boosts tend to over burden the image.

Then I did a mask and a colour saturation to the stars but did not include the nabula. I used a gaussian blue of aroun 4 pixels on the boundary. The reason I did this is the stars are not fully saturated and I thought need a greater saturation.

After this I did a little smoothing via a double mask with only just a slight amount of guassian to each side of the mask.

It goes to show how much data you did get, but I still think longer subs would have helped.

Edit. it is still a little blue but some adjustment in the blue channel will make this look more natural.

allan gould
04-08-2011, 11:27 AM
Paul
Certainly don't mind at all as we are all here to learn. Could you post the repro. Thanks.
Allan

Paul Haese
04-08-2011, 11:30 AM
Done Allan, you will find it in my explanation post.

strongmanmike
04-08-2011, 12:25 PM
Nice work Alan, not sure about all these variations not that much difference really - they each have their good points...maybe do a blend of all three? :thumbsup:

MIke

allan gould
04-08-2011, 04:00 PM
I'll leave it to you to do the Sidonio!
I have about ten other images I'm working on as I had the time to do 3-4 hr for each image at Astrofest and really I was pleased what the VC200L could capture with the QHY8. A nice relaxing imaging session with some pleasant company.

h0ughy
04-08-2011, 06:15 PM
like the lot of them Mr Vixen

allan gould
04-08-2011, 08:21 PM
Ah, grasshopper. You will have to be the sly fox to get what you have "won" past SWMBO!!
Love to be a fly on the wall:D