Deep Spiral

[Peter Ward]

While not in the same league as M&T's 70 odd hour epic, this is my deepish
take on the Helix nebula.

Still a work in progress, with the intention of adding OIII plus RGB data as the weather allows.

I decided to try using my QHY600M on this, but have been be-devilled by low level banding which, even with epic dithering,
has still not delivered a CCD-smooth sky...,but has picked up some remarkably faint stuff (the lower left chevrons and upper left shock fronts).

It was however very satisfying to see the data I was getting from the 'burb's was consistent with M&T 20" CDK version.
Quite a few "deep" images on the web have suspect processing that show nebulosity in places where there is absolutely none. :shrug:

The link is here (http://www.atscope.com.au/BRO/gallery528.html)

[h0ughy]

Given the covidity of the situation I think it looks impressive, with my eyes it looks great

[multiweb]

Impressive. :thumbsup::thumbsup::thumbsup: You've got all the bits. This one to go deep is pretty unforgiving. Unless you're in space.

[Startrek]

Peter,
Nice to see a real image of the Helix with all it’s hidden detail , not my half baked attempt last week with budget low end gear
Beautiful image !!
Really enjoy seeing what’s coming out of your Obs lately
Keep them coming
Cheers
Martin

[Peter Ward]

Ta Martin. Your renditions are fine...and just so we are clear they are accurate as well. :thumbsup:
I was researching other "deep" efforts which just didn't add up...showing Ha in places where there is none.
Hard to know what/why but I suspect inaccurate calibration and over-zealous processing may have been in play





Thanks guys. I had some deep CCD data from my Honders, but it lacked the resolution this set has. Anyway, a good "lock-down" project for sure :)

[AdamJL]

Excellent capture of the fine details in the centre, and the capture of incredibly faint nebulosity at the fringes. A very hard target to shoot.

[gregbradley]

Wonderfully sharp and detailed. Are you using the latest driver? I don't see any banding in my QHY600m. There was a driver update a few months ago for the banding.

Also make sure your gain is high enough. For narrowband I use Mode 1, Gain 56 Offset 50.

Greg.

[Peter Ward]

Hello Greg, Ta. I am indeed using the latest drivers. The banding only shows with extremely faint object imaging.
I actually use Mode 2 with a gain of 80 and offset of 20 for NB. Curiously with a target like M8 the background is smooth as...I only ever see it when there is not much flux in the scene.
I'd certainly be curious to see how your CDK fares with the 600M and Helix.



Thanks. Very kind.

[gregbradley]

Hello Greg, Ta. I am indeed using the latest drivers. The banding only shows with extremely faint object imaging.
I actually use Mode 2 with a gain of 80 and offset of 20 for NB. Curiously with a target like M8 the background is smooth as...I only ever see it when there is not much flux in the scene.
I'd certainly be curious to see how your CDK fares with the 600M and Helix.

See the read noise, 2nd graph for the QHY600M.

https://www.qhyccd.com/qhy600m-c/ scroll down a long way.


Mode 1 has high read noise at gain 80. Whereas Mode 0 has a bit less than half and takes advantage of the dual gain amplifier where read noise drops at Gain 56. Hence the use of gain 56.

My take on it is Mode 2 is useful for objects with high core brightness like a glob or Horsehead with Alnitak.

But I have seen light banding in the past like you mentioned. Just none for quite a while once I settled on the 3 sets of settings I use.

Greg.

[markas]

Great detail:thumbsup::thumbsup: Look forward to the colour version...
Mark

[rustigsmed]

awesome as usual Peter. Interesting to see the qhy600 used with a longer focal length - seems to work absolutely fine!

[JA]

It looks great Peter :thumbsup:
Hopefully you'll bring on the colour &/or NB version so we can look deep in to the eye.

Best
JA

[petershah]

thats deep....looking forward to some colour

[LKD]

Impressive detail

[Andy01]

Very promising start Peter, those outer chevrons are elusive! :thumbsup:
Curious to see your colour rendition eventually.

[Paul Haese]

Go for 40 hours I say. Looking to the left of the outer chevrons and towards the edge of the frame I can see what look like pillows of gas (very very faint). The extra integration should reveal if that is real signal or not.

[Peter Ward]

Ta Paul. I went 40 odd hours with this one a while ago with my AP305mm RHA and frankly didn't gather much more.

What signal is there has been well and truly mapped by M&T's ultra deep
image (link here (https://photos.smugmug.com/photos/i-8NCj6fP/0/X4/i-8NCj6fP-X4.jpg)) which is the bathyscape window reference as far as I can tell.

I'm unlikely to devote the required week or two, imaging from my less than dark site to go any deeper....that said...a higher resolution AO version might be possible.... we shall see! :)