Work in progress - Antennae

[marc4darkskies]

I wasn't going to post this because of the abysmal seeing conditions around here for the last 2 months. I only used 16 out of 47 15 minute subs and even their quality was much less than I'd normally use at 2.7 arcsec FWHM. :sadeyes: :mad2:

Beggars can't be choosers though, so I processed anyway and did the best I could to get a reasonable result. Depth is OK and there are plenty of faint fuzzies but I can only imagine what the result would have been if I'd been able to use 47 subs with good seeing!

Luminance only, cropped for composition:
http://www.pbase.com/gailmarc/image/163198418/original

Cheers, Marcus

[Paul Haese]

Still a good luminance Marcus. I'd keep plugging away if it were me. You are bound to pick up more good seeing at some point soon. It should be on my re-image list too. I take it you do a mask to reveal your star streams and reduce back ground noise?

[strongmanmike]

Ha ha well, despite the unChilean seeing...your mastery of decon has served you quite well Marcus Jucarkis, looks pretty good :) and as for the seeing....take what we get huh? Otherwise our rigs would just sit there....effective cost per use can be pretty expensive in this hobby :lol:

Mike

[Atmos]

There is still a lot of detail on the galaxy, there is only so much that can be done with less than optimal seeing however.

On my iPhone it looks like there is some star elongation running from 2 o'clock to 8 o'clock. Not noticeable on the brighter stars, could this be increasing the FWHM? It is only very slight.

[marc4darkskies]

You're too kind gents! :thanx:



Thanks Paul. Yes, worth plugging away but will have to wait till next month now I think. After that it may be next year.

I use masks liberally and there are many ways to create them but the streams were quite pronounced in the raw stack so I didn't have to work too hard at all to show them clearly.



Thanks Mike! Hehe, "un-Chilean", that's a generous way to describe the conditions. Underwater would be more apt I think! :lol: So yes, I certainly did apply liberal decon here ... and I'm glad it isn't too obvious. Cost per image??!! AAAAaaaaargh!! I feel sick to my stomach now! :lol:



Cheers Colin. No significant elongation I can see but there may be some very minor misshapenness after processing given the seeing conditions. Just don't zoom in too much and make sure your astigmatism isn't corrupting the view (as it sometimes does with my eyeglasses if I cock my head when looking at images)! :D ;)

[multiweb]

That looks terrific Marcus. :thumbsup: Gee, you're a tough customer with the seeing. :lol: If you hadn't mentioned it I wouldn't haven't noticed, not that I can see anything soft in your shot.

[codemonkey]

Looking good, Marcus! I expected worse based on your comments on my effort about your seeing being so poor, but you've done very well in teasing that detail out.

The streams have come out very well in yours, must be those longer subs (900s vs 144s).

I think I can spot some ringing artefacts from decon around some stars overlaying the galaxies, but I had to look pretty hard.

Looking forward to seeing the finished product!

[Atmos]

It's probably a combination of my poor eyes, looking at it on an iPhone is harsh light & processing Artefacts :P

[Placidus]

Hi, Marcus,

Already looking very fine. The tidal tails have come out very well.

Thought: Can you do a separate version using all the subs, which would give even deeper tidal tails and distant background galaxies. Then register that version with this. Combine using a mask based on blurred regional brightness, so you take the bright detail from your best subs, the tidal tails and deep background from the whole stack, and pro rata in between? I'd love to see the result.

Best,
Mike

[gregbradley]

Looking pretty good there Marcus.

I am surprised you say the seeing has been poor as where I am recently it has been pretty good most nights. I am not that far away but I suppose its far enough away to have local effects.

I agree with Paul. A couple of good nights will sharpen it up. The detail in the galaxies are already pretty sharp so some good nights could make it spectacular.

We have an excellent week of weather forecasts ahead so apart from the Moon setting later and later there is an excellent chance of good seeing coming up.

Greg.

[marc4darkskies]

Cheers Marc! Yes, at 3130mm I need to be fussy about seeing. My normal cutoff is 2.5 arcsec FWHM



Thanks Lee! Artefacts can arise in several different ways if you're not careful. In this case probably masking artefacts since my decon is usually not heavy enough to produce dark rings.



You must be an old codger like me Colin! :)



Thanks a lot Mike. Yes, I've actually done that. There is a little less noise in the sky and the fainter parts of the Antennae and streams show up marginally better. The rejected subs are really (I mean really) bad though, so no additional detail and very little additional depth (esp with stars and galaxies) is available. It's also quite hard to restrain stellar profiles after layering and masking! Having said all that, if I use my imagination a bit, the field does look a bit richer. I may fiddle with it some more and replace the current version if I can see a definite improvment.



Thanks Greg. You've got a couple of hundred metres on me don't forget - I'm only at 64m. Not going out tonight but the seeing forecast doesn't look great.

[Peter Ward]

I feel your pain with the seeing....never great my way either. That
said, good looking data so far :thumbsup:

[marc4darkskies]

Thanks Peter!

By the way, I updated the image with data from all the crappy subs. Waste of time really, there wasn't much to salvage from them. In any case, galaxy extents are a little bit smoother and there's a bit more signal for the faint fuzzies (though I doubt anyone would notice). The seeing for the bad subs was between 3 and 5 arcsec FWHM (!!), so given I had to mask off the stars (fuzz balls) and galaxy detail (noodle soup) there was no additional depth gained to the image.

[gvanhau]

I Like your preliminary ressult.
Hope you have enough time to compleete it this season.

Geert

[RickS]

Very nice result, Marcus, despite the seeing. Excellent detail and depth.

Cheers,
Rick.

[gregbradley]

Thanks Greg. You've got a couple of hundred metres on me don't forget - I'm only at 64m. Not going out tonight but the seeing forecast doesn't look great.[/QUOTE]


Seeing was poor initially last night but cleaned up by 10-11pm. What do you use for your seeing forecast?

Greg.

[marc4darkskies]

Thanks very much Geert!



Cheers Rick! I've had a taste of what my rig can do under good seeing conditions ... and I want more!! :)



Forecast for tonight at Grose Vale: Transparency excellent (90+%) until about 1:00am after which it may drop to 80%. Chance of intermittent high cloud after 1:00. Seeing ranging from 6 in the early evening to 7/10 (fair to average) throughout the the rest of the night. :D:P

Like everyone else I use a combination of SkippySky for seeing and transparency and Cloud Free Night for cloud cover. Between the two of them, you can do a pretty accurate forecast IMO.

[Shiraz]

pretty fine result for that level of seeing. Your processing has brought out some excellent detail in the core region and the transition to the lower res outer regions is not noticeable.

[Flugel88]

Nice Antennae Marcus.
Shame about the seeing it has been terrible up in Newcastle area for me too :(.
some Nights i can't even guide with stars bouncing around like crazy and there have been lots of nights with high thin cloud cover.

I hope you can get some good data to polish your image off before it gets to late in the season.

[Rex]

That's a fine result Marcus, especially since you tossed most a lot of the data. Man I wish I had seeing like yours, if I made my cut off at 2.5 fwhm, I wouldn't have any sub's to stack lol. That's the trouble with living up here, always warm and humid. Looking forward to seeing the end result.

[marc4darkskies]

Thanks very much Ray! It was a bit of work teasing out the detail though and keeping it looking real. My kingdom for a few nights of good seeing.



Cheers Michael. If I don't get a chance during the next lunar cycle it will be next year.



Thanks a lot Rex! The best seeing I get around here is 1.7 arcsec FWHM and that's quite rare. 2.0 is much more common. Boy, what I wouldn't give for some altitude and less humidity!