CTB1 - Supernova Remnant
Supernova Remnant in Cassiopeia
RA: 23h 59m 12s; Dec: +62° 23′ 33″; Dist: ~5200 ly
CTB1 Supernova Remnant
Imaging Instrument 4 Inch Refractor at Prime Focus
Focal Length 530 mm
Focal Ratio 5.0
Imaging Camera QSI 683ws-g
Guiding Instrument OAG via QSI IGP
Guiding Camera Starlight Xpress Lodestar X2
Image Capture Sequence Generator Pro
Guiding PHD v2
Image Processing PixInsight
Total Image Frames 556
Total Image Time 125 hours
Filter Frames Exposure Elapsed Time Start Date End Date
Lum 140 180 sec 7 hours 17-Aug-2017 16-Dec-2017
Red 72 300 sec 6 hours 17-Aug-2017 15-Dec-2017
Green 72 300 sec 6 hours 17-Aug-2017 15-Dec-2017
Blue 72 300 sec 6 hours 17-Aug-2017 16-Dec-2017
100 1800 sec 50 hours 17-Jun-2017 18-Nov_2017
Oiii 100 1800 sec 50 hours 17-Jun-2017 19-Nov_2017
Imaging Locations Ft McKavett TX
General Nathan Twining Observatory NM
Kenton OK - Okie-Tex Star Party
San Ysidro NM - White Ridge bicycle trails parking lot
Tijeras NM
Other Image Sizes
Full Resolution Image - email me
Big Image (3000x2400)
Large Image (1200x960)
Medium Image (900x720)
Small Image (600x480)

Object and Imaging Notes
The distance estimation (~5200 ly) is from Distance of "Three Supernova Remnants from H1 Observations in a Complex Region: G114.3+0.3, G116.5+1.1 and CTB 1 (G116.9+0.2)" by Uyaniker, et al, July 2003.
CTB1 is also known as Abell 85. Additionally, the brighter part, towards the bottom of the ring in this image, is LBN 576, from Lynds Bright Nebula list. The name "CTB1" refers to CalTech "B" List, from Table 2 of the paper "A Survey of Galactic Radiation at 960 Mc/s" by CalTech's R.W. Wilson and J.G. Bolton.
Abell listed the object in his planetary nebula list. Later the object was comfirmed to be a supernova remnant.
The object is very dim. As you can see, it doesn't appear visually in the pure luminance, green, and blue channels and is barely visible in the red channel. One really needs narrow-band imaging to capture the object's details.
The composite luminance channel (below) is a combination of the pure luminance, Hα, and Oiii channels. This provides the luminance support for the two high-quality narrow-band channels.

Objects near CTB1
Annotated Image

Channel Images
Composite Luminance
Inverted Composite Luminance
Pure Luminance
Hydrogen Alpha
Hydrogen Alpha
Oxygen III
Oxygen III