Urban Abell 85

Here is a work in progress.  I've added another three hours to the exposure so I was able to be more aggressive with the stretch. This shot was taken from my urban driveway on the edge of a red zone with bortle 6 to 7 skies.

This one is a target on my challenge list as it is extremely faint with very low contrast compared to the
sky background. CBT-1 or Abell 85 is a supernova remnant (SNR) in Cassiopeia. This SNR was cataloged by George Abell as a planetary nebula in his now well-known catalogue as Abell 85 but it was suggested by van den Bergh in 1960 and later confirmed by Willis & Dickel in 1971 to be a supernova remnant.  CTB 1 is approximately 9784 light years away and physically spans another 98 light years in diameter while it is dated to be approximately 10,000 years old. In the full field image the remnant is about the same size as the full Moon.

This version adds another 120 minutes to the exposure and as a result I was able to dial the noise reduction back a bit preserving more detail. The rich star field presents a challenge for star reduction, fortunately Images Plus has a great function for this.

Click on the image to see a higher resolution version of the data. Click again to return to this view.


Object Abell 85, Object RA 23:59:13, Dec +62:28:32
Date 16 January, 2021 and 8 September, 2021
Exposure 5 hours (20 X 15 minutes)
Conditions Average transparency, average seeing, high light pollution (Bortle 6) with a first quarter Moon for half the exposure
Gain 100
Camera Zwo ASI2600MC-Pro
Optics Prime focus of a  SkyWatcher Esprit 120 f/7 APO refractor with a focal length of 840 mm
Filter Optolong L-eNhance
Location Bedford, Nova Scotia
Processing This image was captured using Sequence Generator Pro and processed using a split star process entirely in Images Plus. Because of the short exposure and high light pollution from my urban imaging site a lot of noise reduction was used.