Ngc 6164

[rustigsmed]

I attempted this a while ago in narrowband, which was fairly challenging experience for me. Managed to get some rgb last week.

The first shot is an attempted HaRGB blend and the second pure RGB. My setup has had some pretty bad tilt issues while far from perfect this is an improvement so happy with that. I also bought RegiStar - wow what an effective program. The HaRGB blend doesn't really appear much different perhaps I need to try some of the other blending options.

Anyway I love this little target, it looks like a jewel, i'll probably do repro fiddling with blending methods and maybe even add some O3 data I have in there and try and bring more of the shockwave out :thumbsup:

HaRGB
https://www.flickr.com/photos/80336656@N07/17804683519/in/dateposted-public/lightbox/

RGB (full frame)
https://www.flickr.com/photos/80336656@N07/17964201046/in/dateposted-public/lightbox/

Any pointers appreciated especially on which blending methods I should use in registar.

Cheers

Russ

[gregbradley]

That looks very good Russell. As you say the O111 will bring out more of the shockwave which is also in Ha but mostly in O111.

Greg.

[RickS]

Very nice, Russ. What does the straight Ha look like as a mono image? Adding Oiii would definitely add to the image but you may need a fair amount of it.

I've only attempted HaRGB a few times and haven't been conspicuously successful, so I don't have any advice to offer on that topic...

Cheers,
Rick.

[rustigsmed]

Thanks very much Greg, I really enjoyed your recent widefield version (you had the shockwave nicely!).



Thanks Rick ... hopefully not 70hrs! I think you're right I'm pushing it uphill a bit! My NB subs were only 10 minutes and while its a 12" f4, it is a dslr and uncooled.

Also I generally save from DSS to tiff format, RegiStar only likes 16bit tiff (but can handle 32bit FITS) so I might think about a restack...
Actually a recapture, might try and take longer nb subs now that I've got a bit of a handle on the tilt issue the existing Ha data is poor and probably not adding much at all https://www.flickr.com/photos/80336656@N07/17354733625/in/dateposted-public/
Conditions are looking alright tonight, I might try and nab a few hrs of OIII.

[Placidus]

Hi Russell,
The core is already looking very good.

Your excellent back to back comparison of the H-alpha RGB and straight RGB provides a superb tutorial example of why using H-alpha as a luminance channel doesn't always work. The OIII is not co-located with the H-alpha. The G and B channels from the RGB already pick up some of the outer OIII ring, but the use of H-alpha as luminance actually blocks almost all of that.

If the photographer is interested in is the nebula, rather than the stars, the best thing to do is to just use H-alpha and OIII, and not bother with RGB at all.

There are many other examples where the H-alpha and OIII are almost totally separated in space, especially in nebulae in the greater and lesser magellanic clouds, and there is consequently no place for H-alpha as a luminance channel. Same applies (to a lesser extent) to other WR nebulae such as Thor's Helmet, and to many SNR's and planetary nebulae. All these objects are best photographed in H-alpha and OIII.

Once again, good work.

Very best,
Mike

[Ross G]

Great capture Russell.

A very nice looking photo.

Good luck.

Ross.

[jase]

Very nice Russ. HaRGB is my pick. I assume you're adding the Ha data to the Red channel. HaRGB blends I found are little more work on OSC set up. Needing to extract the red channel first, etc. Mono is the way to go, though some would say that's just as much work.

I'm not sure I understand your question regarding registar. I wouldn't use it to combine images. Registering your subs is fine but I found the data rejection algorithms to be a little archaic. Pixinsight or CCDStack are likely a better choice. There is good info in the registar help file on stacking etc. I'm a visual guy and like to see what is being rejected, CCDStack does just that, highlights in each sub what pixels are seen as outlier data. You can then fine tune the multiplier to reject more or less. I would state that registar is a good upgrade from DSS. Most importantly go with a tool set you understand what its doing to your data.

Look forward to seeing more.

[rustigsmed]

ok this has crashed 4 times trying to post here.......... :mad2:
so i'll be brief.

thanks for your comments Mike Ross and Jase, i've learnt a bit from blending, thank you. and i take your point on the registar data being hidden.

In the quest for the outer shell i realised i need to push the subs to atleast 15 mins. my previous sub max was 10 mins. did a 10er to see if everything was working. all good. then 20 mins all good so went for 30 all good. so here is a blend of RGB and Oiii (no Ha). i've got some shell woohoo (but probably a bit overtoasted - i always seem to redclip in LAB curves).

So good to know i can punch out 30 min subs now but this thing probably needs hour length subs!

Big version below:
https://www.flickr.com/photos/80336656@N07/17932724679/in/dateposted-public/lightbox/

happy for now but no doubt more experimenting to come.

Cheers

Russ

[Placidus]

Hi, Russell,

That is a tremendous improvement. No other word for it.

Best,
Mike

[gregbradley]

I agree, a big improvement and high grade image.

Greg.

[strongmanmike]

Wow Russell, quit a nice improvement using OIII huh? :thumbsup:

Can you not add the Ha too..?

Mike

[RickS]

That made a big difference! Nice improvement, Russ.

[Rod771]

Lovely deep colour on the latest image, Russell!

Very nice! :thumbsup:

[rustigsmed]

Thanks Mike and good to chat over the email yesterday too :thumbsup:



Wow thanks Greg that's very kind.



Yep bigtime Mike, moreseo I think taking longer enough subs to collect enough photons to see it, I never appreciated just how faint it is - well most things are just really starting adding NB. I really like you version its super colourful. have just added a Ha mix, i'm not sure it has added much but its more natural looking.



Thanks Rick for the encouragement along the way :thumbsup:



Cheers Rod :thumbsup:


had another go, this time combined 70 mins of 10 min O3 subs, a 20 min sub and the 3x 30mins (pretty much all the oxygen I had). Not sure it added much perhaps more noise from the sub length mismatch blended with Blue, then the Ha to the Red. and left the Green standard. seems maybe a bit noisier in the core especially but perhaps more naturalish colouring. Will leave it for now till I can get more data.

thanks for the comments and encouragement everybody :thumbsup:

RHa G BO3 bigger here
https://www.flickr.com/photos/80336656@N07/17988515870/in/dateposted-public/lightbox/


Rusty

[Leonardo70]

Wonderful Russel. Congrats.

All the best,
Leo

[cometcatcher]

That's really great. Heaps of outer shell. I'm jealous. :)

[multiweb]

Great fov. I like the Ha blend. :thumbsup:

[rustigsmed]

thanks very much Leo



Thanks Kevin, nothing an Oiii filter and some longer subs can't fix!



Thanks Marc, yes i still think the Ha blend has a better core than the HaO3RGB version.

Clear skies :)

Russ

[Stevec35]

Very nice Rusty. I like it a lot.

Cheers

Steve

[Bassnut]

Sharp, many stars, that move-the-mouse shifting thing is a head spin, tricky work.

[rustigsmed]

Thanks Steve :thumbsup:



thanks Fred - sorry about the stars :P i'm yet to venture into that dark art - yes the move zoom feature feels like it should be inverted.

[Leonardo70]

Very nice, congrats.

All the best,
Leo