this was processed using the addition of the O-III signal to the R&B in appropriate proportion and then photometrically color corrected to the star color in PI, i.e. I think the color is right.
Please note how few subs are used in this image, these are the best of more, but I recently ran into a Topaz AI tutorial by Trevor Jones that helped me tweak the settings to get maximum noise removal and sharpness. I could add more subs, but I have a lot of targets on my list.... and I am not sure that doubling the number of subs will add much detail here.
Trevor Topaz TweaksTechnical info on the PN:
H. E. Bond, Department of Physics and Astronomy, Louisiana State University, writes: "The central star of the planetary nebula Abell 46 (R.A. = 18h29m.2, Decl. = +26o53', equinox 1950.0) has been found to be an eclipsing binary with an orbital period of 11h19m. Observations with high-speed photometers and 0.9-m reflectors at Louisiana State University and Kitt Peak National Observatories reveal a primary minimum 48 min in duration and 1.4 mag deep (in the B band) due to a partial eclipse of the hot component of the system. The light curve exhibits a hump 0.5 mag high near orbital phase 0.5, caused by strong heating of one hemisphere of the cool companion. The secondary eclipse is about 0.1 mag deep. Heliocentric times of primary minimum are given by JD 2444350.8214 + 0.47170 E. Aside from the slightly lower inclination, Abell 46 is remarkably similar to UU Sge, the eclipsing nucleus of Abell 63 (Bond, Liller and Mannery 1978, Ap.J. 223, 252). UU Sge and the central star of Abell 46 are now the only two known definite close-binary nuclei of planetary nebulae."
GENERAL NOTE ON ABELL (and other) PLANETARY NEBULA>>>>>>>>>>>>>
From Wikipedia:
The Abell Catalog of Planetary Nebulae was created in 1966 by George O. Abell and was composed of 86 entries thought to be planetary nebulae that were collected from discoveries, about half by Albert George Wilson and the rest by Abell, Robert George Harrington, and Rudolph Minkowski. All were discovered before August 1955 as part of the National Geographic Society – Palomar Observatory Sky Survey on photographic plates created with the 48-inch (1.2 m) Samuel Oschin telescope at Mount Palomar. Four were later rejected as not being planetaries: Abell 11 (reflection nebula), Abell 32 (red plate flaw), Abell 76 (ring galaxy PGC 85185), and Abell 85 (supernova remnant CTB 1 and noted as possibly such in Abell's 1966 paper). Another three were also not included in the Strasbourg-ESO Catalogue of Galactic Planetary Nebulae (SEC): Abell 9, Abell 17 (red plate flaw), and Abell 64. Planetaries on the list are best viewed with a large aperture telescope (e.g. 18-inch (0.46 m)) and an OIII filter.
It turns out to my surprise most of these are visible with my Stellarvue 130mm (5-inch) SVX.
Bottom line there are 79 imagable Abell Nebula of which I have imaged 51 (half-way point Feb 6 2021).
This is my collection:
Planetary Nebula (Abell)These are sorted by number and behind the Abell's are other miscellaneous PNs that I have imaged... I have a list of the 100 brightest.
These are some useful Abell relevant sites:
Color and IMHO Best Filter InformationImages by Season and More Filter information in German
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