HFG1 and Abell 6 are two planetary nebulae in Cassiopeia that lie in close proximity to each other but are formed from very different mechanisms.  Imaging data was collected over several years (late 2021, 2022 and 2023).  I decided to go "deep" on OIII in an effort to possibly reveal more of the OIII "hood" around HFG1.  Additional parts of the aft portion of the "hood" were revealed but were extremely faint.  Also, Abell 6 began showing some very faint clouds or structure surrounding the nebula itself (slightly brighter in OIII than Ha) and were visible just above the background noise.  See revisions for an inverted extremely stretched OIII image.  Overall, while I'm happy with the image, the amount of total integration time didn't appear to make for a proportionally deeper image than one using perhaps just half the data.

HFG1 (Heckathorn-Fesen-Gull 1) is a planetary nebula discovered in 1982.  It was produced by the binary star V664 Cas with a period of about 14 hours.  A bow-shock is produced as the stars plough through the local interstellar medium (ISM) during periods of mass ejection while also leaving a long trail of emission in its wake.  HFG1 is estimated to be 10000 years old.  The range of possible distances to V664 Cas is 310-950 parsecs (1000-3100 light years).  [Monthly Notices of the Royal Astronomical Society 396, 1186-1188 (2009), P. Boumis, et al, "A long trail behind the planetary nebula HFG1 (PK 136+05) and its pre-cataclysmic binary star V664 Cas"] and [Astronomy and Astrophysics 310, 603-612 (1996), K.M. Xilouris et al, "The shaping of aging planetary nebula"]

Abell 6 is a classic bubble-type planetary nebula with a magnitude of around 15.  Not much information is available on its distance, but one estimate is about 3100 light years.  It has a stronger OIII emission than in Ha. 

Taken over several nights:  Nov 20; Dec 12, 14, 19-20, 22 and 26, 2021.  Jan 3, 5, 7, 11, 15, 18; Oct 5-6, 2022.  Oct 7, 13, 18, 23-25, 27; Nov 10, 12-13, 16-18, 20, 2023.