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marc4darkskies
28-05-2011, 01:31 PM
A few clear nights in Sydney and what happens? A mad rush to image before the clouds return (sorry - a bit pessimistic).

I haven't finished this one yet but I thought I'd post anyway as a work in progress. So far so good - only preliminary processing has been done so still a way to go!

This is a faint one for sure - especially through a 5.9" and with Ha filter!!:help: Most of the signal you see is the Ha component. The Lum is just filling in the stellar profiles a bit and exposing the few small bits of reflection near in top in the dark part.

Hopefully RGB will follow in the next few days! :prey:

Small:
http://www.pbase.com/gailmarc/image/135068508/large

Large:
http://www.pbase.com/gailmarc/image/135068508/original

Cheers, Marcus

strongmanmike
28-05-2011, 01:48 PM
Looks exactly as I would expect it to look Marcus ie excellent

Some good exposure time there and the addition of the Lum has brought out lots of stars, which in this field actually looks good.

The colour version will look fantastic, ahhh I can see it already :thumbsup:

Mike

renormalised
28-05-2011, 01:53 PM
Looking good, Marcus. Will be a top shot when it's finished:)

gregbradley
28-05-2011, 04:37 PM
Looking good Marcus.

A bit of fuzziness on lots of the stars though. Its from overflow from the pixel wells.
Was that in the Luminance or the Ha or both?

30 minutes for Ha or 20 minutes for Lum may be too long for the 60,000 electron
wells of the 11002 chip. Length of exposure has too much noise with too short on one side versus
oversaturation with long exposures on the other side. It depends on the well depth and noise levels of the camera
and the cooling ability.

Greg.

multiweb
28-05-2011, 04:48 PM
That's a great shot Marcus. An excellent sharp base to do colors from. :thumbsup:

Peter Ward
28-05-2011, 05:15 PM
To quote H. Simpson..... Huumm Doughnuts :) Drool....

marc4darkskies
28-05-2011, 06:11 PM
Thanks Mike - appreciate that! :thumbsup: Yeah can't wait to get the colour but wouldn't you know it .... cloudy tonight, same with showers tomorrow, rain on Monday and showers all next week!!! :sadeyes::mad2::sad:



Thanks Carl! I was pleasantly surprised at the resolution although seeing wasn't the best. It wasn't bad though.



Hehehe ... methinks you're too used to 17 inches of aperture. 5.9" at F11.7 requires long subs - especially on a faint object like this! Max ADU is 51,000 odd for the brightest of stars in Lum (at the bottom of the frame) and 59,000 in Ha. Yep, they're pretty well saturated but the sub length is aimed at revealing the subject so I'm happy to sacrifice a few stars for that. Really, any overly fuzzy stars you see (?) are because this is a work in progress. :) Cheers mate!



Thanks Marc - still hopeful I can gather some RGB before the moon comes back!



Thanks Peter! I trust you mean Krispy Kreme doughnuts? ... With lots of icing .... and 100s and 1000s? ... Mmmmmmm

troypiggo
28-05-2011, 08:06 PM
Wow. Appetite whet, looking forward to the next installments.

gregbradley
29-05-2011, 01:00 AM
Hehehe ... methinks you're too used to 17 inches of aperture. 5.9" at F11.7 requires long subs - especially on a faint object like this! Max ADU is 51,000 odd for the brightest of stars in Lum (at the bottom of the frame) and 59,000 in Ha. Yep, they're pretty well saturated but the sub length is aimed at revealing the subject so I'm happy to sacrifice a few stars for that. Really, any overly fuzzy stars you see (?) are because this is a work in progress. :) Cheers mate!


Yes that is true. It is a spectacular image and very nicely framed. It is impressive that you can get such round stars for so long a period at F11.7.

Greg.

marc4darkskies
29-05-2011, 06:21 PM
Cheers Troy. Dying to finish it - I just need the cloud gods to blink.



PME = round stars :D

I think framing / composition is often underated as an essential ingredient of a striking image. I always devote some thought to what I want the final frame to look like and often crop just to make it right. I haven't decided this is the final composition yet, it may change when the colour is added.

Thanks again!

Phil Hart
29-05-2011, 08:57 PM
very impressive marcus.. that seems very deep to me.. 7 hours sure but f11.7.. and you're not even in really dark skies? i'm amazed at what you can do.. :thumbsup:

marc4darkskies
29-05-2011, 11:35 PM
Thanks Phil! You're too kind!

Yes it's quite deep but Ha is good for piercing the sky glow if you have the patience to gather the data. My SE sky is pretty well blotted out from the light dome over Sydney so I may have to wait till after transit for the G and B data. Everywhere else is reasonably dark though.

TrevorW
30-05-2011, 12:45 PM
Very nicely captured plenty of detail

Hagar
30-05-2011, 07:15 PM
I Love the detail in this one Marcus. Should be a contender for the pool room once you add some colour. Very nice.

marc4darkskies
30-05-2011, 09:57 PM
Cheers Trev!



Thanks Doug! I might just have to build that pool room too - I'm running out of wall space in the study! :) Doesn't look like colour is comining any time soon ... the cloud and rain is back :mad2:

gregbradley
31-05-2011, 07:47 AM
Ah doubter! Friday is supposed to be partly cloudy! You never know your luck.

Why is it for the last 2 years that the full moon weeks are often far clearer than the no moon weeks?
Have a look at the pattern its almost 100% of the time. Is it like a tide thing with moisture in the air
dragged to other areas in the full moon week?

Greg.

Leonardo70
31-05-2011, 05:57 PM
WOW ....
Fantastic resolution....

Ciao,
Leo

Bassnut
31-05-2011, 06:24 PM
Excellent Marcus, atmospheric in B/W.

marc4darkskies
31-05-2011, 08:50 PM
Yeah but I hate it when I have to stop in the middle of a project! Grrrrr ... :mad2: I guess "Partly Cloudy" will have to do. I'd prefer to see "Fine" for the next week though! And I think you're right about the coincidence of full moon with clear skies. Hey! Maybe we should consult an astrologer to see when the next best imaging nights will be!? :lol:



Thanks a lot Leo. Yes, the 1.6 Extender on the TOA works a treat in good seeing and really shows off the top quality of Tak optics!



Cheers Fred! Hopefully I can maintain and/or enhance that atmosphere with the colour.