Helix Nebula

[Jon]

Helix Nebula. I had no idea planetaries could get this big.

24 x 4 min subs at ISO 1600. I might try again tonight and collect at least twice as much data, go for 50 x 5 mins and see what difference that makes.

[Larryp]

Nice image, Jon!

[alistairsam]

Hi Jonathan,

stacking more subs would reduce noise but if you're going for 5 mins, I'd suggest 800iso to keep noise low.
I'd also suggest dithering the subs, that would give you better noise reduction when stacking.
what ota were you using?
Colours and guiding look great.
Cheers

[Jon]

Hi Alistair,

Good advice. I've been meaning to work out the dithering function on BackyardEOS/PHD. I was using the 10" Meade SCT with f/6.3 flattener/reducer.

[rcheshire]

Jon. I agree with Alistair. Out of interest what is the focal ratio of the scope? Are you urban or rural?

[Jon]

Urban, sadly. Last month I moved from a rented shack in the middle of nowhere to a house in suburban Canberra. On the edge, thankfully. And Canberra's better than some places.

The scope is 2540mm - an LX200 Classic 10". I was using the f/6.3 focal reducer/flattener for this capture.

[rcheshire]

You could try as low as iso400. Slower integration may provide better control over star colour and size and increase dynamic range. Personally, I find 1600 too high. The image is quickly dominated by sky glow due to light pollution.

[DavidNg]

Hi Jon,

Good work again for this small nebula. I noted the stars appeared to have bloating appearances ( I could be wrong), so as a learning experience I downloaded your image without prior consent and did some deconvolution and morphologicaltrans in PixInsight and minor brightness, contrast and saturation in PS. Hope you dont mind :)

Here is the reprocessed image, not sure if that makes any difference.
Regards
David

[Jon]

Don't mind at all - I must learn this processing witchcraft! Looks like I'm going to have to invest in pixinsight :-)

[Logieberra]

Nice Jon. Are you shooting from the suburbs or outskirts of town?

[Jon]

3km from you, Logan, if this locator thingy is to be trusted! I'm in Latham, but my balcony faces East, so the Helix was rising over Westfield Belconnen at 2 am as I took these subs :-)

[Logieberra]

Nice. You're in the 'glow bubble' too. Dunlop. Good shot from the burbs.

[Gem]

Nothing wrong with astro in Canberra! :)

[Jon]

I do suspect our light pollution is better than the big cities like Sydney and Melbourne. We're very spread out, have a lot of modern street lighting, and the altitude helps too. When I moved a month ago from a sheep farm out on Uriarra Rd into the suburbs, I bought a CLS filter. I've only used it once visually and never photographically.

[Logieberra]

G, your images are a testament to that. Yes, we're doing OK in Canberra burbs :)