This is a narrowband bi-colour image based on test data from a new obsy being commissioned in New Mexico.
Approx 4 hours of Ha and 9 hours of Oiii captured with a Tak FSQ-106ED and QSI683.
The result is heavily magenta, but you'd expect that when mixing Ha and Oiii The Crescent Nebula, NGC 6888, is pretty obvious. It is a large gaseous shell created by the Wolf-Rayet star HD 192163. In the middle of the image towards the bottom is a much fainter planetary, PN G75.5+1.7, aka the Soap Bubble nebula.
That's a cracker of an image Rick. Great to see the soap bubble in the same fov. Did you perform any star size reduction to get the nebulosity to come through? The Ha/OIII blend looks spot on. Very nice.
That's a cracker of an image Rick. Great to see the soap bubble in the same fov. Did you perform any star size reduction to get the nebulosity to come through? The Ha/OIII blend looks spot on. Very nice.
Thanks, Jase. I removed the stars almost completely from the Ha and Oiii used to create the base colour image to prevent halos from the much bigger stretch needed for the Oiii. I also did some star reduction on the Luminance. I always do with this scope/camera combination as it tends to produce bloated stars.
Thanks, Jase. I removed the stars almost completely from the Ha and Oiii used to create the base colour image to prevent halos from the much bigger stretch needed for the Oiii. I also did some star reduction on the Luminance. I always do with this scope/camera combination as it tends to produce bloated stars.
Rick, could you not just use the stars from the Ha filtered subs alone. I would imagine they present a small stellar profile given the narrow bandpass of the filter. Would be easier, yes?
Rick, could you not just use the stars from the Ha filtered subs alone. I would imagine they present a small stellar profile given the narrow bandpass of the filter. Would be easier, yes?
Jase,
The Ha definitely had tighter stars but I couldn't use the Ha as Luminance by itself because there were significant features that were only visible in the Oiii (the blue shell around NGC6888 and the whole Soap Bubble.) So, I built the Luminance with PixelMath from the original Ha and Oiii. I suppose I could have used the starless Oiii in this process and I would have ended up with just the Ha stars but I would have needed to clean up some of the artefacts in the starless Oiii.
Ideally, I would have some RGB stars to plug in to the image but alas I don't...
Did that answer your question or did I misunderstand you?
I like this one. Really like the bubbles in this image. The processing is very nice except I don't like the orange near the top. Other than that I really think it is a fabulous image.
As always, an image that pleases the eye and teaches a thing or two about data processing. Thank you Rick for sharing.
Thank you, Slawomir! I'm just making it up as I go along
Quote:
Originally Posted by jase
Yes, thanks Rick. I didn't realise there were artefacts in both Ha and OIII data sets. Good job at masking them up.
Only after I removed the stars, Jase. I do find it worthwhile for narrowband colour. It solves all those issues with horrible coloured star halos. That's the big technique I picked up from JP Metsavainio's tone map processing.
Quote:
Originally Posted by DavidTrap
Fantastic image Rick - can't believe this is "test data"...
DT
Thanks, David. We have high standards for our testing
Quote:
Originally Posted by SkyViking
A splendid image with a lot of definition and detail. Love the soap bubble too
Thanks for the view Rick.
Thanks, Rolf!
Quote:
Originally Posted by cometcatcher
Lovely image Rick! I didn't know about the soap bubble.
Ta, Kevin. I had heard of it but wasn't really sure where it was until it I was looking over the Oiii data at full res and it just popped out!
Quote:
Originally Posted by Paul Haese
I like this one. Really like the bubbles in this image. The processing is very nice except I don't like the orange near the top. Other than that I really think it is a fabulous image.
Thanks, Paul. You wouldn't believe how hard I tried to stop the orange bit turning magenta and getting posterized! It really is a different colour to the rest of the background
The Crescent Nebula, NGC 6888, is pretty obvious. It is a large gaseous shell created by the Wolf-Rayet star HD 192163. In the middle of the image towards the bottom is a much fainter planetary, PN G75.5+1.7, aka the Soap Bubble nebula.
