This has always been a fascinating object. Delicate flower like structure and shockwaves from the powerful O type star that irradiates it that is 40 times more massive than our Sun.
It is a lovely region Greg and nicely handled. The shock wave interaction towards the bottom of the stellar region is fascinating
It is and from what I have read the theory is the shockwaves are from an early stage of the Type O stage development. Obviously its blown its stack at some point. Its a supernova candidate in the future.
Quote:
Originally Posted by RickS
Very nice, Greg! Lots of dim Oiii visible for a relatively short total integration.
Life is fast at F3.8 and also at 17 inches of aperture! Thanks Rick.
Quote:
Originally Posted by marc4darkskies
A nice looking image of an interesting object Greg!
Consider getting rid of the blue cast perhaps? RGB stars will look richer. You seem to have black clipped your red channel as well - sorry
Thanks for the critique. I revisited it and fixed the clipped red. I found out which step did that it was the colour balance tool. Blue is a bit more balanced but still quite a bit of it. This is a Ha O111 LRGB image so its more narrowband than RGB (LRGB just for the stars really) so the blue is part of the O111 data as far as I can see. Cheers Marcus
Quote:
Originally Posted by Andy01
The cosmic coffee bean!
Nice image Greg, does look a bit blue but it's so pretty, like a backlit neon
Thanks Andy. I looked at the blue again and its pulled back more. I think its correct now for the Ha O111 data set I have. Thanks Andy. Same link.
You've convinced me that the large, faint patches of OIII at 10 o'clock and 11:30 and almost at the edge are real. Because of our smaller FOV I'd dismissed it as bad flats.
Best,
Mike
PS: I've just seen what you mean by a delicate flower-like nebula. The two faint patches I mentioned are petals. There are more. Never seen that before.
You've convinced me that the large, faint patches of OIII at 10 o'clock and 11:30 and almost at the edge are real. Because of our smaller FOV I'd dismissed it as bad flats.
Best,
Mike
PS: I've just seen what you mean by a delicate flower-like nebula. The two faint patches I mentioned are petals. There are more. Never seen that before.
Thanks Mike. I just checked the O111 master again and it definitely shows that area as brightish compared to the rest of the frame.
Also I realised this is actually 4 cameras, not 3. The FLI Proline 16803/CDK17 for some Ha, The Trius 694/RHA Ha and O111, ST8300/RHA full set, Microline 8300/TEC180 full set. I think the total exposure time may be longer than I added up. There was a lot of data from the Trius, several nights worth and its about the most sensitive CCD there is in O111 at about 66%QE plus the F3.8 of the RHA it picks up a lot very quickly.
Colour is ok Greg in my opinion. I found that when I did this I got a similar cast top and bottom and put it down to gradients at the time but since then I have seen a few images with a similar look. No doubt there is a lot of Ha one side and on the other a lot of OIII on this target. In the end I chose a slightly less blue colour palette but I think you are reasonably close to what comes out of the camera.
Your detail levels are not bad either, though I suspect you are hampered by the lowest resolution setup. I reckon it would be preferable to image with the CDK for get maximum resolution at your dark sky location. Its a wonderful object up close and worth putting in the hours at a higher resolution.
Still some noise drifting around, but I found I had to do a lot of hours before it started to diminish. I am betting most of the noise is from the OIII as I found it very noisy.
Overall I like the look of the image, but would like to see you get a lot more data yet.
Not much I can add other than: nice image, I like it.
I'd like to see a "closer view" though of the centre - it looks just as interesting in itself.
Thanks for that. I'll do a crop, yes I agree there is some great detail in there from the CDK17 data.
Quote:
Originally Posted by Retrograde
Beautifully done as usual Greg. That shockwave really is something.
A nice compliment - thank you. The shockwave is amazing. It reminds me of Vela.
Quote:
Originally Posted by Paul Haese
Colour is ok Greg in my opinion. I found that when I did this I got a similar cast top and bottom and put it down to gradients at the time but since then I have seen a few images with a similar look. No doubt there is a lot of Ha one side and on the other a lot of OIII on this target. In the end I chose a slightly less blue colour palette but I think you are reasonably close to what comes out of the camera.
Your detail levels are not bad either, though I suspect you are hampered by the lowest resolution setup. I reckon it would be preferable to image with the CDK for get maximum resolution at your dark sky location. Its a wonderful object up close and worth putting in the hours at a higher resolution.
Still some noise drifting around, but I found I had to do a lot of hours before it started to diminish. I am betting most of the noise is from the OIII as I found it very noisy.
Overall I like the look of the image, but would like to see you get a lot more data yet.
Thanks Paul. More is always good for sure. I agree the CDK could do an even nicer version. I may just do that as its in a good position at the moment.
Now its all fully setup and tuned its ready for business. It was not quite ready when I took the Ha but because the object was really in the centre of the image the corners didn't matter.
Greg.
Last edited by gregbradley; 27-06-2016 at 01:02 PM.
Lovely and delicate. I was thinking same as Marcus re blue, but am viewing on iPhone not calib monitor.
Thanks Troy. Its the O111 that is the blue and I looked at the O111 master again and its definitely there. A lot of the data was imaged using the Trius 694 which is 66% QE in O111 which I think is the most sensitive of any CCD plus it was on the RHA which is very fast at F3.8 so it collects a lot of light very quickly. Perhaps twice as fast as many other scopes. 12 inch and F3.8 is a good formula, demanding in terms of precision but the advantages are the speed of data collection. I think its ideal.
So its picked up actual O111 that probably is not normally picked up. But I did check the processing of colour after Marcus commented on that and I did tone down the blue compared to where it was when he commented. So its less blue than it was!
You've convinced me that the large, faint patches of OIII at 10 o'clock and 11:30 and almost at the edge are real. Because of our smaller FOV I'd dismissed it as bad flats.
They show up in my long Oiii integration too. I should try a repro some time...
