NGC7293 - The Helix Nebula

cybereye (Mario) · #1 28-11-2011, 10:51 PM

Well it seems forever since I posted something in this section of IIS!!

Last night we had a clear night in Brisbane, so despite the wind and heat (27C at 9pm) I decided to try and image the Helix Nebula. I've never imaged a Planetary Nebula before so I was keen to give this a go.

Due to the wind I ended up going for 2 minute subs as these seemed to be better behaved than longer ones. I took 70 images but only managed to get 50 usable ones, totaling 1 hour and 20 minutes of subs.

After much processing the result is a tad noisy but if I try to push it any more then it only makes the noise worse.

Imaging was done through my 8" newt on a HEQ5 Pro mount using my QHY8L. Guiding was done using an Orion ST80 and a QHY5 and control was done bby PHD - when it behaved!! A Baader MPCC and UHC-S filter were used and stacking was done in DSS.

Processing was done in StarTools and the resultant image is attached.

Cheers,
Mario

cybereye (Mario) · #2 30-11-2011, 07:37 AM

As I was far from happy with my efforts processing first time around I went back and reworked my data last night. What I thought was noise turned out to be faint nebulosity which encircles the Helix. However I'm now thinking that 2 minute exposures were not long enough to do this object justice.

In order to try and overcome this I did a 2x2 binning midway through my processing. I didn't push the wavelets as hard and didn't zoom in as much.

I'm happier with the newer image but think I need to get out and get some longer exposures....

Mighty_oz (Marcus) · #3 30-11-2011, 10:23 AM

I like the second version

Seems the stars appear smaller and sharper. Much cleaner as u can see, the more data u have the further u can push it. If u can do longer exposures then go for it, but if not than just do a heap more . The beauty of digital is that u can just add to what u have, even years down the track.

renormalised (Carl) · #4 30-11-2011, 08:25 PM

Nice shot, Mario

I agree with Marcus, the second image has a but more punch to it...sharper and brighter. Given the crap (hot and humid) weather we've been having, I wouldn't try to push the exposure length too far. Heaps of 2 min subs would do well.

Ross G · #5 11-12-2011, 03:15 PM

Well done Mario.

I like the colours.

Ross.

midnight (Darrin) · #6 12-12-2011, 01:52 AM

Nice presentation too Mario. The 2nd one is much better and you've got those colours working too.

Darrin...

cybereye (Mario) · #7 12-12-2011, 07:49 AM

Thanks everyone for your comments on my image.

I was actually trying some processing stuff on this image last night but can't really improve on what I've done so far. I'd like it to be a little bit brighter but I think I need to add in some more information to be able to stretch it a little bit more. Having said that I too am happy with the colours.

I'll be back out there soon to try and get that data but I can't do anything at the moment due to the clouds and rain!!

Cheers,
Mario

gregbradley · #8 12-12-2011, 07:52 AM

A good shot Mario.

Helix is a very faint nebula and it takes long exposures and long total exposure to get enough signal to work it very hard. Your tracking is particularly perfect.

Greg.

cybereye (Mario) · #9 13-12-2011, 07:15 AM

Quote:

Originally Posted by gregbradley

A good shot Mario.

Your tracking is particularly perfect.

Greg.

Greg,

When I was imaging I wasn't very happy with my tracking (from individual subs), yet after stacking 50 images in DSS, the stars came out almost perfectly round. I'm not sure what happened there but I wasn't complaining!! I only needed a very, very slight adjustment to the stars in StarTools to get the result you see.

Thanks for your comments,

Cheers,
Mario

cybereye (Mario) · #10 13-12-2011, 04:30 PM

Well this is amazing!!

Ivo Jager noticed this thread yesterday and picked up on my comments regarding the noise problem I was having with this dataset. He contacted me and said that he had a few tricks up his sleeve with an upcoming release of StarTools and would I mind if he tried some of these on my data. So I sent him the data and within a day came back with this result which he said was a quick play with the data.

I was truly gobsmacked on two counts when I opened the email that contained his version of my data. Firstly I was struck with just how much he'd improved the detail and clarity of the Helix including the surrounding faint nebulosity and secondly I can't believe that this sort of data is possible from a hill in Brisbane!!

Amazing, just amazing - thank you Ivo!!

Mario

multiweb (Marc) · #11 13-12-2011, 05:42 PM

Nice round stars. Good shot.