The Tarantula Nebula is more than a thousand light-years in diameter, a giant star forming region within nearby satellite galaxy the Large Magellanic Cloud. About 180 thousand light-years away, it's the largest, most violent star forming region known in the whole Local Group of galaxies. Within the Tarantula (NGC 2070), intense radiation, stellar winds and supernova shocks from the central young cluster of massive stars, cataloged as R136, energize the nebular glow and shape the spidery filaments. Were the Tarantula Nebula closer, say 1,500 light-years distant like the local star forming Orion Nebula, it would take up half the sky! (Apod)
Big one Here (if Astrobin is working - wasn't loading before)
Spend a couple of nights dialing back in the NJP & collimating the 'scope after all the recent mods. Some of the powder coated surfaces were causing a couple of internal locknuts to slip, so PA and guiding were temporarily affected, but I'm 99% on top of that now.
Chose a target that I could image in a single night, and the biggest, brightest option was good old NGC 2070. This one was inspired by the workflow of Josep Drudis using just Ha & O3 and adding back the RGB stars.
Considering it was taken from my light polluted suburban backyard in Melbourne, I'm pretty happy with the result!
That is probably the nicest image you have done in my opinion. Not a big fan of ultra violent looking images, its dealers choice I suppose.
At full res you appear to have some fixed pattern noise present in the dark regions and some sharpening artifacts. This is probably to be expected because of the short imaging run on one night. The normal presentation on Astrobin looks good and hides those problems. Only pixel peeping will see any problems. Anyway I am sure you are aware of the minor warts.
I had another look at the high res image Paul and I am not seeing that at all.
Its with a 12 inch nice display on a laptop. Its not a large 4K monitor. Perhaps only a super high res large monitor would show that.
I love the colours and ghostly vibe that you have going on there.
Best
JA
Thanks JA - "Ghostly Vibe", I like that
Quote:
Originally Posted by gregbradley
A fabulous image. One night's worth? Wow, you have your gear humming!
I like the star colours and the overall colour blend. Its good to see a narrowband image with a nice range of colours.
Greg.
Cheers Greg, my original plan was to gather some S2 as well, but I ran out of dark time - so bicolour it became, glad you enjoyed it
Quote:
Originally Posted by Nikolas
Beautiful Andy you must be really close to me I'm in Glen Iris
Hey Nikolas, thanks very much! Yes I'm in Burwood
Quote:
Originally Posted by Paul Haese
That is probably the nicest image you have done in my opinion. Not a big fan of ultra violent looking images, its dealers choice I suppose.
At full res you appear to have some fixed pattern noise present in the dark regions and some sharpening artifacts. This is probably to be expected because of the short imaging run on one night. The normal presentation on Astrobin looks good and hides those problems. Only pixel peeping will see any problems. Anyway I am sure you are aware of the minor warts.
Cheers Paul - Turned out surprisingly well for a single nights imaging. No doubt more data would produce an even smoother result, but given this was a shakedown run, I'm delighted with the result and it feels great to be imaging again!
Quote:
Originally Posted by gregbradley
I had another look at the high res image Paul and I am not seeing that at all.
Its with a 12 inch nice display on a laptop. Its not a large 4K monitor. Perhaps only a super high res large monitor would show that.
Greg.
Thanks Greg - I saw the FPN that Paul mentioned as well when I was processing the data set masters. As mentioned above, it would probably be eliminated with more data. Now if someone could just move those pesky clouds along....
Nice and bold rendition, of what is a pretty cool area in any book, lots of gas...and... it looks like gas too, so well done on that score The fixed pattern noise is only visible in a few places, weird..?
Good to be back in the fold I bet ......after desecrating your beautiful green Tak gear
Nice vivid outer regions Andy. I think that perhaps the Tarantula itself is too muted by comparison. Regarding the FPN: I see it now (on my iPad) but only because others have pointed it out. I probably would have missed it if left to my own devices.
I’m all for constructive criticism. It helps to lift the bar for everybody, not just the imager.
Geoff
The fine detail in the tarantula is superb. There's a little cluster right at the bottom, about 7 o'clock. You've shown the colours of the cluster stars beautifully.
Nice and bold rendition, of what is a pretty cool area in any book, lots of gas...and... it looks like gas too, so well done on that score The fixed pattern noise is only visible in a few places, weird..?
Good to be back in the fold I bet ......after desecrating your beautiful green Tak gear
Mike
Thanks Mike, yes overall I'm very happy to be back imaging again!
Tell me IIS Team, what is the cause of FPN? I'm curious
Quote:
Originally Posted by Geoff45
Nice vivid outer regions Andy. I think that perhaps the Tarantula itself is too muted by comparison. Regarding the FPN: I see it now (on my iPad) but only because others have pointed it out. I probably would have missed it if left to my own devices.
I’m all for constructive criticism. It helps to lift the bar for everybody, not just the imager.
Geoff
Cheers Geoff, by muted did you mean the brightness/colour? It's an exceptionally bright object and I didn't want to lose the dynamic range, so I went for highlights with Juuuust enough detail, rather than making it look too flat.
Quote:
Originally Posted by Placidus
The fine detail in the tarantula is superb. There's a little cluster right at the bottom, about 7 o'clock. You've shown the colours of the cluster stars beautifully.
Cheers M&T, yes, that's the O3 detail showing up mostly, and thanks also for the feedback on the cluster! I'm very happy with the star colours especially considering the LP here in Melbs.
Quote:
Originally Posted by Ryderscope
You’ve captured the swirling detail and colours beautifully Andy.
Cheers Rodney, seems that it's a crowd pleasing target
A pleasing spider's lair. As for the colour, while not accurate has certainly has some pizzaz....dare I say, hallmarks of an Andy C image
Fixed pattern noise is due a very low level, but constant variation in sensitivity across the sensor. More typically seen in CMOS due the way each pixel is read-up, but CCD's are not immune. Interline sensors such as the KAI 11000 suffered from the dreaded "jailbar" pattern. Can't say I've seen it in non-interline CCD's such as the KAF16803, plus if there is a fair amount of signal, FPN also disappears into the background.
The easiest fix is to dither your sub exposures...and the more the subs the merrier...any fixed pattern should slowly decay due a process not dissimilar to gaussian blur by doing so.
Last edited by Peter Ward; 22-09-2019 at 12:11 PM.
Reason: typo
Cheers Geoff, by muted did you mean the brightness/colour? It's an exceptionally bright object and I didn't want to lose the dynamic range, so I went for highlights with Juuuust enough detail, rather than making it look too flat
[\QUOTE]
Hi Andy. The Tarantula comes out pinkish and pink is really a desaturated red, so I guess I’m saying that the nebula loses a bit of punch in comparison with all the stuff surrounding it.
A pleasing spider's lair. As for the colour, while not accurate has certainly has some pizzaz....dare I say, hallmarks of an Andy C image
Fixed pattern noise is due a very low level, but constant variation in sensitivity across the sensor. More typically seen in CMOS due the way each pixel is read-up, but CCD's are not immune. Interline sensors such as the KAI 11000 suffered from the dreaded "jailbar" pattern. Can't say I've seen it in non-interline CCD's such as the KAF16803, plus if there is a fair amount of signal, FPN also disappears into the background.
The easiest fix is to dither your sub exposures...and the more the subs the merrier...any fixed pattern should slowly decay due a process not dissimilar to gaussian blur by doing so.
Cheers Peter, and thanks for the explanation- sounds like more data required!
[QUOTE=Geoff45;1447006]
Quote:
Originally Posted by Andy01
Cheers Geoff, by muted did you mean the brightness/colour? It's an exceptionally bright object and I didn't want to lose the dynamic range, so I went for highlights with Juuuust enough detail, rather than making it look too flat
[\QUOTE]
Hi Andy. The Tarantula comes out pinkish and pink is really a desaturated red, so I guess I’m saying that the nebula loses a bit of punch in comparison with all the stuff surrounding it.
I think that’s right Geoff. Dr. Malin was very specific at the DMA 2015 presentation about 2070 being rendered as a brilliant, very bright object - so that makes sense
...after desecrating your beautiful green Tak gear 
