Excellent weather conditions for the last week in Sydney allowed quite a bit of imaging time, and with the moon down, thought id try LRGB again.
Was a bit of a shock, its been a while since ive tried LRGB, processing is so hard with heavy light pollution, narrowband is much easier, processing wise anyway .
I never do flats for NB, just dont need em, but did for this image, and discovered a nasty little problem I havent even heard of before. AO dances the image around so that flats dont fit that well (taken with AO off), your left with halos around where filter dust donuts are on the flats. They seemed to dissappear (or get hidden) somewhat during processing, but never the less a disturbing discovery.
Anyhoo... M83 for your pleasure at my site home page here, with gaud awefull stars and next to no colour in them, I hate those bugggers, just gave up (well, M83 would look pretty daft without them I guess ). Humies recent M83 got the star colour smick, perhaps I could nick them..........
Im happy with outer extension, but the noise was a bit severe.
LRGB :Lum 5hrs, 30 off 10 min subs bin 1 , RGB 50mins each, 10 off 5 min subs bin2
AO was cranking at about 3 hz. Interestingly, it was working hard when I started at about 10pm, and settled right down as the night wore on, and it got nearer the zenith. The AO operation gives a good indication of seeing.
Last edited by Bassnut; 21-03-2010 at 06:42 PM.
Reason: Quick gradient fix
what's with the orientation? Is that just to frame it to
taste, boy you made it hard to cross check for supernovae
Is it mirrored as well? I had to do a mirror and 45 tilt to get it
to match one of my Nth up images.
Lovely detail.
Who cares about the stars -- look at all that gobsmacking detail in the core. Yowza!
One day. One day!
H
Hehe, absolutely one day , I look forward to that day .
Quote:
Originally Posted by DavidU
Mighty effort Fred !Super
Thanks Dave
Quote:
Originally Posted by gregbradley
Great shot Fred. It seems to show that the galaxy is actually slightly at an angle to us. Other images don't reveal that.
You've got a bad gradient in the background though. Top half is very green and bottom half is too blue.
By the way Fred, how large is the corrected image circle from the 12 inch ACF?
Greg.
Yes, now that its dark around my LCD, the gradient is awefull, dont know how that happened. The quick fix is only a bit better, sorry.
Gaud, I dont know what the image circle is on the ACF, but I took a 40D pic with it and the AP 0.67 reducer (I think) and it came out OK.
Quote:
Originally Posted by kinetic
Beautiful Fred,
what's with the orientation? Is that just to frame it to
taste, boy you made it hard to cross check for supernovae
Is it mirrored as well? I had to do a mirror and 45 tilt to get it
to match one of my Nth up images.
Lovely detail.
Steve
Thanks Steve. FITS liberator flips vertically when importing to PS for some unknown reason (I forgot to flip back), and otherwise oreientation is wherever I can find a bright guide star for the OAG AO guide cam with a rotator.
Not to keen on the outskirt of the pic but the central region colors and details certainly smack you in the face as previously said. AO is the way to go for long FL work. The proof is in the pudding. Top shot.
Thanks guys. The smacking brightness and colour is perhaps a bit extreme, but it works .
Marc, yes the skirt aint flash, but its soo painfull to start again . I could just curve it down, but the Galaxy looses its shape then and looks a bit wonky.
Thanks guys. The smacking brightness and colour is perhaps a bit extreme, but it works .
Marc, yes the skirt aint flash, but its soo painfull to start again . I could just curve it down, but the Galaxy looses its shape then and looks a bit wonky.
I reckon image the same spot again in RGB with 5x3 min subs and layer the star colour in... Easiest way to get the colour back without doing anything too difficult or drastic.
.
). Humies recent M83 got the star colour smick, perhaps I could nick them.........
.
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Very nice shot mate! 
