This was very tricky to process for me. I realized that I was going to get nowhere with RGB in my light polluted area as that bright star next to the PN overwhelms everything. So I focused on the NB. Turns out that both HA and O-III have very strong signals.
What I did was very carefully examine the stacked NB and I could see some variation across the PN but had to manually stretch the linear to get a reasonable stretched range of values.
The next step was to use PixelMath to give the correct Teal color for the O-III .72 for G and .88 for B. The R has always been a problem merging in here. I then realized that if I add it at the median value of the G&B, in this case .80, the colors would be proportionally relatively correct, given that both O-III and HA were strong. So, I got a balanced set of RGB colors, which were slightly adjusted via histogram.
I then used a PI GAME mask to isolate the PN and brighten it back to 100%.
The nasty star was tamed a lot by the use of NB but I added back some spikes to return some of its vigor. it is after all Christmas.
GENERAL NOTE ON ABELL PLANETARY NEBULA>>>>>>>>>>>>>
There are 86 in the original list. It looks like 4 are probably not PN and a good number are low on the horizon for me, so it is not clear how many I can do.
To date I have done 31. You can tell I collected stamps as a child....
This is my collection, which includes other PNs, but is sorted by Abell number:
Abell and Other Planetary NebulaeMost are cropped to 500x500 pixels to give an idea of size.
Please note there is also a Abell and a PN Group at Astrobin.
Hope you enjoy these obscure but interesting objects...
Comments