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DiscoDuck
13-06-2019, 08:16 AM
An attempt at NGC 6164 from the wintery Adelaide suburbs.

A lot of the data, especially the OIII, was captured in very poor conditions - dew, bad seeing and poor transparency. This and the fact that the OIII is surprisingly faint and this was taken from the suburbs meant that even with a lot of OIII data it was still very hard to bring the shell out. So the 24 hours of OIII sounds like overkill but is not that great!

About 8 hrs of Ha and 3hrs x 3 RGB for star colours too. ZWO ASI1600MM-C and RC8 on a Mach1. ZWO filters.

I guess I hadn't appreciated how faint the shell was. Almost invisible in individual narrowband subs and not there at all in the RGB!

Also the halos from the ZWO narrowband filters are very noticeable around the brighter stars. Could be time to splash out on Astrodons!

Higher res available on Astrobin here (http://www.astrobin.com/410049/C/)

Paul

Retrograde
13-06-2019, 11:19 AM
Very nice, deep image there Paul.:thumbsup:

multiweb
13-06-2019, 11:56 AM
Superb details and colours Paul. Well done indeed. :thumbsup:

Placidus
14-06-2019, 07:55 AM
One of the best bubbles we've seen :thumbsup:

DiscoDuck
14-06-2019, 09:22 AM
Thank you Pete, Marc and Mike n Trish.

strongmanmike
14-06-2019, 01:26 PM
Great result Paul, well done :thumbsup: Did you collect the OIII with no Moon? OIII should always be collected with no (or very little) Moon in the sky :thumbsup:

Mike

DiscoDuck
14-06-2019, 02:25 PM
Thanks Mike. I think a lot of it was with no to little moon. Frankly by the end I was sick of dew and bad seeing, and was willing to take any clear night. Hence most of the data is of a quality I'd normally bin!! (and I don't mean that in the 2x2 sense! :D ).

codemonkey
14-06-2019, 04:48 PM
That's a helluva effort right there, Paul. Nice one.

DiscoDuck
15-06-2019, 10:09 AM
Thanks Lee.

Bart
15-06-2019, 03:34 PM
That looks very nice Mr Duck, well done! Hows the Mach 1 going for you?



I am having similar halo issues with the Baader filters so when my camera comes back from repairs I am going to try a few things around spacing.

DiscoDuck
15-06-2019, 04:04 PM
Thanks Master Simpson!


I think with the ZWOs the halos are internal reflections and unavoidable. Only $$ can fix it!! :(


The Mach1 is going well thanks - in spite of already being a legacy product with the Mach2 coming out!

Ryderscope
15-06-2019, 08:22 PM
The bubble has popped out quite well Paul. Nicely done :thumbsup:

DiscoDuck
16-06-2019, 11:14 AM
Thanks Rodney.

Paul Haese
20-06-2019, 04:44 PM
Nice going Paul, when I did this I noticed the OIII shell was hard to capture too. It required a lot of time to really bring it out. 24 hours of OIII is a lot though. In any event it is a good image of this target.

DiscoDuck
20-06-2019, 06:09 PM
Thanks Paul. I guess it took longer in the light pollution. That shell is so faint that even in narrowband it is lost in the background noise of light pollution - especially with a bit of a moon up and poor seeing/transparancy.

Paul Haese
20-06-2019, 06:20 PM
I agree with Mike that trying to get OIII in moonless conditions is best and depending on what filter you have. Although I sometimes try to get it due to the 3nm filter I am using. Still it is best to get it when no moon is present.

DiscoDuck
20-06-2019, 06:48 PM
Sounds like solid advice, Paul. This was a 7nm filter too, which didn't help :(
But in winter I guess you take the clear nights you get :)



Now if only the Aussie dollar would improve and make the Astrodons a bit more affordable!

Edit to add: quick back of the envelope calculation shows that with a 3nm filter in (my usual) dark sky site vs my 7nm suburban attempt, 3 hours of OIII should have matched this 24 hour shot in terms of SNR!

Slawomir
23-06-2019, 06:36 PM
A very nice shot of a challenging target Paul :thumbsup:

DiscoDuck
23-06-2019, 06:48 PM
Thank you, Suavi.

willik
25-06-2019, 10:57 AM
That is a very nice image Paul well done.
Martin

DiscoDuck
25-06-2019, 01:30 PM
Thanks Martin.