Helix Nebula

[DiscoDuck]

An attempt at the Helix from a dark sky site (QHY8 and RC8 on an EQ6). Was a tad disappointed that 11 hours under a dark sky gave something not enormously better than a previous 4 hours in the 'burbs.

That said, I suspect the nasty bloating of the bright stars may be due to some dew somewhere in the system?? I had a secondary dew heater but no other heating, and it was bitterly cold. (Odd though that bright stars bloat and yet fine detail doesn't seem too badly affected, nor FWHM of the dimmer stars.)

If so, I guess it'd explain the lack of depth. Even for an OSC camera like this, I'd expect more?? :shrug:

Comments appreciated.

Paul

P.S. Full res on Astrobin here (http://www.astrobin.com/full/308338/B/).

[atalas]

Nice work Paul....some good structure showing....quite an effort with a OSC cam :thumbsup:

[Atmos]

That's really nice Paul! I think what you're running into is the fact that further on from where you are is starting to get significantly fainter.

[Anth10]

A fine example of an eye catching planetary neb. The time you've invested in capturing this image reveals plenty of detail in the middle and outer reaches. Well done.

[DiscoDuck]

Thanks Louie.



Thanks Colin. Yeah. It's a surpisingly big step down in brightness.



Thanks Anthony.

[gregbradley]

A lovely Helix and you've got the first part of the outer Ha areas. Deeper than you realise perhaps.

As far as bloating one shot colour cameras still need a UV/IR filter. Are you using one? I used to used one when I used an STL11 one shot colour.

Greg.

[DiscoDuck]

Thanks Greg. Re bloating, yes, I have a UV/IR filter. The bloat is noticeable comparing with an image taken last year with the same gear of the same target. As I said, it was very cold (ice on table I had my laptop on!) so it could well be just some slight dew/frosting somewhere in the optical path maybe?? (and at least one of the first subs I had the wires for my dew heater in the light path and so that didn't help! :( ).

[DJT]

Hi Paul

That's really pretty good. There's plenty of faint fuzzies in the background which is always good the good detail in the nebula.

20 minute subs, that's impressive. My only comment though is that there's no star colour to speak of which is just an outcome of the longer subs.

You could take shorter subs for the star colour and combine them maybe?

Nice work.

[DiscoDuck]

Thanks David. Great point re star colour. Thanks.

[RickS]

Looks pretty good for OSC, Paul. To get faint details and small stars you really need NB filters on a mono camera and very long integration times.

[DiscoDuck]

Thanks Rick.

[graham.hobart]

Nice Helix!
A question to the responders then- should I be using a UV/IR cut filter then with my 60da (and my QHY 8 pro ) ? plus refractor?
I never thought of that :question:

[el_draco]

Nah.... use a TOA 150 mate... I know you secretly want one!:lol::rofl:

[PRejto]

It's a very nice image! I agree that the bloating of the bright stars is bothersome. Do you know the well size of your chip? The lack of colour + size probably means your subs are too long. Since the read noise of the Sony chips is rather low could you not achieve the same (or better!) result with more subs of shorter duration?

Peter

I agree with Rick's comment that the tightest stars need a mono camera. I was never satisfied with my experiments with a colour Trius and gave up for exactly that reason. Have you ever tried the Pucker Tool in Photoshop? It's located in Liquify and can do an amazing job shrinking stars.

[Stevec35]

I reckon that's pretty good Paul

Cheers

Steve

[DiscoDuck]

Thanks Peter. One point to note is I got less bloating on the same exposure length during another session. I reckon it must be some sort of dew/ice, though I agree shorter exposures are worth a try next time too - not least for colour. Thanks - will give it a go.

Though now to some extent a bit moot as I'm just awaiting my mono camera from Bintel in the mail tomorrow or Monday:)!

Never come across that Photoshop tool you mention. Though PixInsight has what sounds like a similar tool. Might be worth a try too.



Thanks Steve.

[Placidus]

A very encouraging image and nice colours. Quite a few background galaxies showing up. The bright stars don't detract. Definitely worth another night or two if you could stand it.

A mono camera in the mail. H-alpha here we come!

[strongmanmike]

Very nice Paul, a solidly good image of the Helix mate :thumbsup: As for the bloated stars?..really not that bad but I looked at a few other shots at your AB site take with the same equipment and yes the stars in this Helix do look very slightly bloated in comparison but not overly so, I'm thinking your processing may have been slightly different this time, perhaps you stretched differently?

Mike

[DiscoDuck]

Thanks Mike and Trish. :)



Maybe I did. I guess with it being a dark sky site rather than the normal suburbs shot then I may have done something different.

Thanks for the kind words too.

[willik]

Very nice image Paul well done
Martin

[DiscoDuck]

Thanks Martin