Thor's Helmet NGC2359

[Geoff45]

http://www.astrobin.com/70925/
Another one from last weekend.
Telescope: 12.5" Plane Wave CDK
Mount: AP 900
Camera: QSI540wsg
Exposure: 70 minutes each of LRGB (Total 4hr40min).
I also took some Ha but adding it in didn't do a lot for the detail and washed out the nice green colour, so I haven't used it yet.
Geoff

[Bassnut]

Excellent work Geoff, top detail and good star field colour.

[gregbradley]

That's a great Thor's Helmut Geoff.

Greg.

[RickS]

Nice work, Geoff! You must be operating at a pretty small image scale with that set up?

[strongmanmike]

That's an excellent Thor's Helmet Geoff, lovely processing, excellent detail in the dome of the helmet and I like the green too :thumbsup:

Mike

[spearo]

great shot and i love the webpage display
frank

[Geoff45]

Thanks Rick. The FOV with the setup is 21' x 21' at 1024 x 1024 pixels (binned 2 x 2 getting 1.2" per binned pixel), but I often have to crop a few minutes off to align different nights. This one is 1000 x 1000 pixels. Hanging out for the qsi756 with the 16803 chip. I'll get 46' x 46'.
Geoff

[alpal]

Great result Geoff,
That binning at 2x2 has helped to lower the time needed.
I'll be binning everything at 2x2 now on my system.
I was going to do Thor's Helmet but decided it was too
difficult from an outer suburb of Melbourne.
You're lucky to have such dark skies.
Well done.

cheers
Allan

[Geoff45]

Thanks Allan. Re the binning: it seems to me that if I am getting an FWHM of 2+ arcseconds there's not much point in doing bin 1 at 0.6" per pixel.
Geoff

[alpal]

Hi Geoff,
That's my thinking too.
With many camera/scope combos unless you have sub arc second seeing -
you gain nothing on binning x1 for all frames including Luminance -
in fact the picture is much worse.

cheers
Allan

[marc4darkskies]

Very nicely done Geoff! :thumbsup:

Cheers, Marcus

[SkyViking]

What a beautiful image, Thor's Helmet is one of the prettiest nebulae I reckon. Nice work, thanks for the view :)

[rat156]

Hi Geoff,

That's a very nice Thor's Helmet.

There was a discussion here about why binning the RGB exposures is pointless, it's about creating a super luminance. There was a lot of discussion about read noise etc, most of which was totally over my head, but the crux of it was that binning on camera was a waste of time, you don't get more s/n out of the super pixel.

Since then I have not binned my RGB, haven't noticed a difference really. Have you looked at taking un-binned?

This is a good target for imaging from suburbia, as long as you have narrowband capabilities.

Cheers
Stuart

[alpal]

Hi Stuart,
I did some experimental sub frames & posted them on my thread here:
http://www.iceinspace.com.au/forum/showthread.php?t=115824

My post at 31-12-2013, 12:05 PM shows 3 mono pictures
comparing binning 1x1 & 2x2 with 10 minutes of exposure using Ha.
The results convinced me to go 2x2 on everything including Luminance
to increase the signal to noise ratio.



Also -
There is a graph & quite a read here:
http://www.microscopyu.com/tutorials/java/digitalimaging/signaltonoise/index.html

see graph:
http://www.microscopyu.com/tutorials/java/digitalimaging/signaltonoise/signaltonoisejavafigure2.jpg

[Astroman]

Very nice. Was thinking of shooting this myself, but went and did Eta Carin instead. Love the colours you got, very natural looking.

[Ross G]

Great looking photo Geoff.

I love the colour and detail.

Nice composition.

Ross.