Dumbell Ha with outer halo

[gregbradley]

I was pretty excited to get the outer halo of the Dumbell relatively easily with the CDK17 and reducer at F4.45.

15 minute subs at 2x2 binning were showing it using a FLI Microline 8300 at -40C.

It is very low in the north and I can only image it for a short time as the wall of my observatory blocks it for part of the time.

http://upload.pbase.com/image/137123036 Dumbell

Greg.

[jjjnettie]

Congratulations Greg. :D

[Ross G]

Looks good Greg.

Again something I haven't seen before.

Thanks.

Ross.

[jase]

Nice work Greg. I'd be pretty surprised if you didn't pick out the faint Ha shell with 17" operating at F4! I recall when I imaged this target with a 24" RC operating at F8, I needed 900s subs to pick it up. Mind you I was operating with a back illuminated ccd with at peak QE of 98%. Your rendition is coming along well. Hope to see the finished result assuming it doesn't get too low for you to complete the project. Well done.

[gregbradley]

Thanks JJ. I was happy to be able to pick up that detail so low.



Cheers Ross. Its really a northern hemisphere target. It must be about 10-15 degrees up from the horizon here in Sydney.



It wouldn't be the first time a scope didn't do what might be expected though.;)

Fortunately it did. When I first got the CDK17 it would not pick up the Helix practically at all with 10 minute subs and 5nm Ha with a bright moon.

A better secondary shroud, using 2x2 binning, better gradient processing and the reducer make it all work.

Greg.

[bokglob]

Thats excellent Greg, never seen it like that before. Would love to see it in colour:thumbsup::thumbsup:

[strongmanmike]

Yehaaa, easy! ...it's great to have speeeeed, it's amlmost futuristic huh? :thumbsup:

[atalas]

Great stuff Greg! looking forward to seeing It finished.

[gregbradley]

Thanks for that. I have seen it from guys in the northern hemisphere when they image it for a long time. I was happy I could see it in every 15 minute sub. F4.45 rocks!



Yes the 2 mirror, corrector, reducer setup is working very nicely.

2 fast mirrors and a corrector is a great formula.




I did get some RGB but the red which I shot last was unusable as the object was partly behind the observatory wall.

I think a Ha/O111 bicolour may suit it.

And by the way this was shot with the Microline 8300 - nice little camera isn't it? Its about the most perfect defect free chip I have used. Kodak seems to be able to make them defect free more easily than other chips.

Greg.

[Paul Haese]

Looks like a good start to this image Greg. Heaps of detail in the image too.

[gregbradley]

Thanks Paul. I am happy to be able to utilise the 8300 camera as well.

Greg.

[p1taylor]

Greg that is really good outer nebula is coming thru good not really seen so much before.

peter

[gregbradley]

Cheers Paul. I hope to be able to finish it once the moon dies down in a few days.



Thanks Peter, especially here in the Southern Hemisphere where it is a very low object in the northern sky for us.

Greg.

[Stevec35]

Nice one again Greg. Certainly lots of detail that you don't often see in southern hemisphere shots of M27. I hope you manage to get colour.

Cheers

Steve