Abell 35 (SH2-313)

[Ryderscope]

Following on from my work in progress reports (http://www.iceinspace.com.au/forum/showthread.php?t=166088) and 47.5 hours of data later I now present a completed Abell 35 image for posting. Data for RGB was collected and processed separately and then added to Ha/OIII. Processing for Ha/OIII and combining with RGB was executed with my attempt at the J-P Metsavainio tone mapping technique. Deviated significantly off course during processing and very much started making it up was we went along. Made for an interesting journey.

Link to Astrobin image here. (https://astrob.in/full/351533/0/)

Comments and critique welcome.

[Andy01]

Wow Rodney!
47.5 hrs? You didn't leave anything on the table there did you :lol:
Exquisite, One of your very best images I'd say, bravo! :thumbsup::thumbsup::thumbsup:

[Ryderscope]

Thanks Andy, I really did have to keep going with the data collection as the result was too noisy without grabbing as many subs as practicable.

[cometcatcher]

I've actually been waiting for this since your preview. Mind now blown. Best amateur image of Abell 35 I've seen!

[Stevec35]

A terrific image Rodney!

Steve

[strongmanmike]

Excellent result Rodney, your patience paid off with a very fine image of this colourful cosmic potato chip :thumbsup:....most I have ever grabbed on a single object, in 15 years of CCD'ing, is 32.5hrs :ashamed: I tend to get bored after the third night on the same object...so I rarely manage to get over the 16hrs mark.

Mike
snapshot imager :P

[gregbradley]

That is a stunning image. Wow, 47.5 hours, that is very patient. I am similar to Mike there. I think I had an image of about 40 odd hours that was a combo of various efforts over a few years. So 47.5 hours in one go that is fabulous.

The pinpoint stars and excellent processing is the cream on the cake.

Greg.

[Ryderscope]

High praise indeed Kevin. I’m glad I didn’t build the anticipation too much :)



Thanks Steve.



Thanks Mike. I like your description of a cosmic potato chip, that works very well. I kept on with the data collection because my early attempts struggled with the low signal level. Grabbing some additional photons is made a little easier of course when you only have to walk thirty metres to your observatory.



Thanks Greg, I appreciate the feedback. Looks like I might be setting a data collection benchmark to aspire to :D

[RickS]

That's a fantastic effort, Rodney, and a great result. Did you do any noise reduction on the neb? I'm just wondering if a tiny touch of grit would enhance it...

Cheers,
Rick.

[Ryderscope]

Thanks Rick, yes I did noise reduction early on in the processing using a combination of TGV and MMT processes. Possibly could have dropped it back a tad so worth keeping in mind. I did try a touch of unsharp mask at the end but couldn't bring myself to leave it there.

[LewisM]

I'm going to say it... OMFG!!!

Sublime.

[Ryderscope]

Hmmm :question: we wonder what he means?

All good, many thanks Lewis :)

[codemonkey]

Awesome work, Rodney, that's quite an achievement!

[Geoff45]

That’s a really crisp, smooth image Rodney. Those Abell planetaries are often quite big, but so so faint. Nothing short of heroic exposures do them justice and you have certainly achieved this

[Ryderscope]

Thanks Lee and Geoff, much appreciated.

[Placidus]

Wow! Superbly done !!!

Apart from subtleties of colour, yours looks exactly like Don Goldman's version, so it must be good :D

We are going to have to put this one on our to-do list.

[Ryderscope]

Thanks MnT, I hope that you do put it on your list. You system should bring out even more detail.

[topheart]

Excellent work! Congratulations!
Cheers,
Tin

[Atmos]

Fantastic Rodney! Colour and detail is exquisite. Definitely off the beaten track!
Out of curiosity, did you do star removal? Or anything with the MorphologicalTransformation?

[Ryderscope]

Thanks Tim.

[Ryderscope]

Thanks Colin.

Yes, star removal was part of the processing steps but on the narrowband (Ha/OIII) channels only. Stars were removed at the beginning of the process using a combination of star masks and MT (Erosion). Clean up done with the clone stamp tool. Narrow band masters were then processed separately before combining using pixelmath and processed then as a colour master.

The RGB was processed separately to the point that I was happy with the stars and then combined with the narrowband colour master using pixelmath.

This particular image does lend itself to star removal using the MT technique as the nebulosity is concentrated in the centre of the image. It makes it easy to mask it out using a range mask if you need to tidy up the background. Obviously if there is nebulosity scattered across the field it can be a little more of a challenge.

[markas]

Superb image!


Mark

[Ryderscope]

Many thanks Mark.

[PeterSEllis]

That is a lovely shot Rodney. It never ceases to marvel me, the beauty in some of those nebula's out there.

Cheers
Peter

[Ryderscope]

Thanks Peter, we certainly are spoiled for choice for wonderful nebula targets.

[Paul Haese]

This is nice Rodney. I undertook a monster amount of integration on this target and never got enough that I felt happy with brightness and colour.

Having undertaken massive integrations in the past myself (to date my longest was 111 hours on the Helix), I can appreciate the effort you have gone to here. Congratulations to your persistence.

Lovely colour and detail, you have all the bases covered.:thumbsup:

[Ryderscope]

Thanks Paul, I appreciate the feedback. It certainly was a technically challenging project and I’m glad that it came out reasonably well.