NGC1871 nebula in Bi colour narrowband Ha and OIII mapped as LRB.
It has a nifty bonus bubble nebula too . Large here.
Not oft imaged, in fact I cant find a single colour NB image of it on the interwebs .
Although described as a "bright nebula" I dont know how they figure that, for hubble maybe. One site mentioned mag 10, I dont know what that refers to exactly. Id like to describe the scene, but I cant find any info.
The Ha stack after cal, showed a background of 60 ADU, average 100 and a small peak of 500 ADU (for the nebula). OIII was worse at 25 ADU background and 100 peak. I took many hrs of SII but the ADU was 70 or less, just impossible to deal with hence Ha, OIII bicolour.
Taken on an RCOS 10" RC Scope at f9, SBIG STXL6303E Camera and PME mount at itelescopes Siding Spring Observatory over 1.5 mths Oct-Nov.
Processed with CCDstack, Star Tools and Photoshop. 83 hrs Total exposure time.
Bi colour Ha, Ha ,OIII. Mapped as LRB. Ha 75 subs at 40 min bin 1 50hrs total, OIII 50 40min subs bin2 33hrs total.
So, not a lot of dynamic range to play with, processing was a challenge, its about at the limit I can handle with a pokey 10". Its a bit garish and the pallete wont suit everyone. Some RGB was taken for stars, although that didnt help much.
Fred that's utterly awesome! The bow-wave has already been used up so we'll just say
The 83 hours in the saddle has produced a very clean image for such a faint source.
Setting aside the technical difficulty, it's a very beautiful image. The bubble structures are shown well. And contrary to everything we've said, the red/blue palette has worked pleasingly.
Very nice Fred! I just tracked down the region in one of my large mosaics of the area, it certainly is very faint! With 83 hours of time, I can imagine that it would have needed it! Gotta be nice having a telescope perm setup for large integration times
Very cool, Fred! You've been quiet on IIS for a long time but that's making a grand return Some lovely detailed structures and we're used to outrageous colours now thanks to Andy and others... maybe even me a little
Top stuff Fred, looks ok for the sparse data you hve. Good effort!
Thanks Bart, vast numbers of subs sure helps!
Quote:
Originally Posted by Andy01
Ka-chow Fred, you sure didn't leave anything on the table there
That's a big, bold and dramatic image of a rarely seen target, bravo!
Well done sir
cheers
Andy
Well, thanks Andy !. I was aiming for dramatic relative to difficulty at least, its lacking the sort of 3D effect monster data can provide, I just couldnt make it.
Quote:
Originally Posted by Somnium
spectacular effort there ! lovely work
Cheers Adian, appreciated.
Quote:
Originally Posted by Placidus
Fred that's utterly awesome! The bow-wave has already been used up so we'll just say
The 83 hours in the saddle has produced a very clean image for such a faint source.
Setting aside the technical difficulty, it's a very beautiful image. The bubble structures are shown well. And contrary to everything we've said, the red/blue palette has worked pleasingly.
Thanks M&T, I tried the red/yellowish pallete many use lately, I like that too, this one seemed best. The stack was pretty clean but still needed work, less than Ive had before though.
Quote:
Originally Posted by Atmos
Very nice Fred! I just tracked down the region in one of my large mosaics of the area, it certainly is very faint! With 83 hours of time, I can imagine that it would have needed it! Gotta be nice having a telescope perm setup for large integration times
Cheers Colin, yes, just clicking go everyday is sure helpfull, but leads to very intermittent posting of images. Its a constant battle, post common bright often, or rare sometimes. Its just as much fun making bright nebs super sharp with semi-megadata. Im tempted to do that next, or god forgive, a galaxy in RGB, that usually goes very south for me
Quote:
Originally Posted by gregbradley
Top work Fred. Its great to see a rare object. Hobbyists doing science really.
Greg.
Thanks Greg, thats funny, I dont think I could be accused of doing science, I dont actually give a rats if an image is scientifically accurate, art is far more important
Quote:
Originally Posted by RickS
Very cool, Fred! You've been quiet on IIS for a long time but that's making a grand return Some lovely detailed structures and we're used to outrageous colours now thanks to Andy and others... maybe even me a little
Thanks Rick, images once a mth or so is a bit quieting, and you know, one waxes and wanes with posting voracity. I should post responses to images from others really, Ive been a bit slack. Certainly, you and Andy have had a huge influence on my processing, and others . The biggest change for me was colourising channels and much more use of clipping masks, it gives far more non-destructive variation in processing to match the new kind of mapping you guys have come up with.
Quote:
Originally Posted by Ken
You put some serious time and effort into this Fred, great job.
Clear skies Ken.
Thanks Ken. The longer capture is not that much harder being remote, but in this case processing did take some time.
Quote:
Originally Posted by rogerg
Wow, I'm astonished you have such a nice result from such low ADU. Fantastic image!
Thanks Roger. Even though the dynamic range (bit depth) was low, the number of subs made all the difference noise wise, although I still couldnt get the kind of 3D effect everyone strives for. I must say, just the unique noise reduction feature in Startools is gold and very hard to do manually with masks in PS etc, its a huge time saver.
While I don't recognise it, t'is certainly a unique looking image Fred, I like that cool looking ring on the left. Lots of exposure to process there, must have been fun ...I haven't cracked 20hrs on one object (without combining separate projects) since mid 2010
I keep coming back to that magnificent red ring just above the midline at far left. Would love to know what it is. I'd guess SNR, because there's no obvious culprit inside as there would be if it were a WR nebula.
A few more nights and total exposure would have been in triple digits
Thanks Suavi. Diminishing returns is getting savage already, id have to get into many triple digits to make any more improvement
Quote:
Originally Posted by PRejto
Very impressive, Fred! Your huge effort has really paid off. It may be a tough act to follow!!
Peter
Cheers Peter, nah, the bar is constantly raising, I have trouble keeping up, you make it harder yourself
Quote:
Originally Posted by atalas
I'm with the rest of the guys on this Fred...quite spectacular
Thanks Louie
Quote:
Originally Posted by strongmanmike
While I don't recognise it, t'is certainly a unique looking image Fred, I like that cool looking ring on the left. Lots of exposure to process there, must have been fun ...I haven't cracked 20hrs on one object (without combining separate projects) since mid 2010
Nice to see you back
Mike
Thanks Mike. I wasnt away, just quite, lurking, enjoying your work for one actually !. The hrs have downsides, you seem to just not need them as much anyway
Quote:
Originally Posted by Placidus
I keep coming back to that magnificent red ring just above the midline at far left. Would love to know what it is. I'd guess SNR, because there's no obvious culprit inside as there would be if it were a WR nebula.
Ive tried to find what it is. Astrometry.net didnt indicate anything from memory, and now its not working to check again. Ill keep looking.
you and Andy have had a huge influence on my processing, and others
Nice of you to say so Fred but I think the boot's on the other foot! You have been a massive influence on my imaging so thanks for the nice compliment as it appears to have come full circle
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