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gregbradley
14-07-2011, 05:42 PM
I took this the other night I took the Helix Halpha.

Again the beginnings of a narrowband image.

Planewave CDK17 with reducer giving F4.51.

15 minute subexposures and Vixen 95VMC guide scope with SBIG ST402 camera.

2 hours and 30 minutes.

http://www.pbase.com/image/136407602

I am really starting to like my CDK now.

Greg.

multiweb
14-07-2011, 05:54 PM
oooh yeah! Sweet shot. :thumbsup::thumbsup::thumbsup:

alan meehan
14-07-2011, 05:55 PM
Nice image Greg shows some lovely detail to the outer edges ,almost 3d
AL

John Hothersall
14-07-2011, 06:28 PM
My goodness that is a stunner, lovely round stars and detail just shines, superfast especially for S2 will work so well.

John.

Paul Haese
14-07-2011, 07:10 PM
Nice stars, great data, lovely field (which is what I get with the TSA). Only thing I would do is to use curves to make the image a bit darker. I had a little play and I think the contrast and detail looks a lot better when the image, particularly the nebula, is slightly darker. Great to see such an image so close up and I would imagine at hi res as being pretty interesting looking.

DavidTrap
14-07-2011, 07:20 PM
I agree with Paul - I was going to say something smart like "you need to stop it down". Out of curiosity, what was the "well count" (not sure of the correct term) for the brighter areas of the nebulosity after 15min subs?

I've still working out how to adjust levels & curves for Ha images - I have struggled to find a balance where they look to have depth.

DT

peter_4059
14-07-2011, 07:20 PM
Nice start Greg. It was great to meet you at AAIC.

Peter

RBA
14-07-2011, 07:50 PM
Well, it depends what Greg wants to present in the image. I'm definitely a "let me see the details" type of guy, and there's lots of details in there that could be brought out without sacrificing the fact this is a brutally bright object.

Ross G
14-07-2011, 08:08 PM
Great photo Greg.

It has amazing detail and I love the contrasts.

Thanks.

Ross.

RobF
14-07-2011, 08:29 PM
The thing that really catches my eye is the extent of the neb. You don't normally take in those extremities. Will be keen to see where you head with this one Greg.

TheDecepticon
14-07-2011, 08:31 PM
That is awesome Greg, it will be nice in full colour.:D

CoolhandJo
14-07-2011, 10:08 PM
It's shots like this that give you the reason why it's called the lagoon. The outer rim detail is awesome. :)

Paul Haese
14-07-2011, 10:10 PM
I agree, there is always more than one way to skin a cat too.:)

gregbradley
14-07-2011, 10:39 PM
Thanks Al.



This rig is now pretty awesome. I just recollimated it and it is running a bit better now as well.



Thanks Paul. I had a look and yes I agree. I did another version yesterday that is darker and very contrasty. I looked at it again tonight and I thought naw - it doesn't show enough of the extended nebula. But a bit darker does bring out more detail and folds in the nebula etc. I have posted the new darker version and I think its a bit better.



The 16803 has 100,000 well depth and I'd have to check but I don't think it got oversaturated. Perhaps the very central bright stars in the hourglass nebula only.



Great to meet you too.



Welcome to this forum Rogelio and it was great to meet you and your lovely family at AAIC.



Thanks Ross.



The fast f ratio and large aperture make this a good rig to explore these sorts of things. I hope it will show up detail I haven't seen before.
Being at my home observatory if we get regular clear weather which is starting to happen lately then I can get really long exposure images.



Hopefully in a few days.



That detail came up very well.



Cheers for your input Paul.

Greg.

RBA
15-07-2011, 07:18 AM
Your last version definitely shows a lot more detail in the lagoon area, but as you said, the fainter stuff around it is a bit harder to see.

Adding contrast to bright areas without sacrificing the hard earned fainter signal is not hard. I'm not a big fan of curves - most people can achieve good results with them, but I just can't :)

For this, I think in Photoshop the Shadows and highlights tool might be your friend, I don't know if that's what you used. In PixInsight the HDRWT tool will do wonders, especially if used with a luminance-based mask that protects everything but the brighter areas.

But in the end it comes down to what your goals are, of course!

gregbradley
15-07-2011, 08:28 AM
Thanks for the tips Rogelio. I did that and I agree its an improvement.

Cheers mate.

Greg.

atalas
15-07-2011, 12:42 PM
Nice work Greg.

marco
15-07-2011, 02:03 PM
Impressive result Greg, perhaps a bit too "flat" IMHO. Furthermore, I would love to own a piece of equipment as yours :thumbsup:

Reading the former comments, I find always amazing how we all look at the same image with different eyes, some preferring it lighter, some darker, not to mention the big debates that color images always rise..

Clear skies
Marco

gregbradley
15-07-2011, 02:04 PM
Thanks Louie.

I spent about 3 hours collimating the scope last night and it seemed to be sharper afterwards and round stars to the corners with the reducer which is quite an optical feat. Its not that hard to collimate however not quite as easy as the manual implies either!

Greg.

jase
15-07-2011, 05:36 PM
Dramatic image Greg, remarkable in fact! Pleased to see you ironing out the folds in your set up. Looking forward to seeing more from this 17" F/4.5 configuration.

Bassnut
15-07-2011, 05:54 PM
mmm, compressed to hell Greg. I had a fiddle in PS, theres a lot of detail there thats just buried.

gregbradley
15-07-2011, 08:01 PM
Cheers Louie.



Yes it is a bit flat and perhaps what I need to do is some short exposures for the core to complement the longer exposures for the detail and get an HDR image going.



Thanks Jase. The reducer seems to work magic for my area where the seeing is average to poor at times. More to come on this one after some more clear nights.

''

I'll be adding more data to this and doing O111 and S11 so I'll revisit it later.

Its a tricky one with the high dynamic range from the little black dust areas to the bright central core. It probably needs an M42 type approach.

Greg.