Chaple's Arc is a mini asterism described by Glenn Chaple in 1980 while looking for the colorful double star HJ 1470 in Cygnus. It is a nearly circular arrangements of mostly double stars. HJ 1470 is seen at 1 o'clock. Its star pair are mag 7.4 and 9.2 The ring has a 22 arc-minute diameter and so barely fit in my original FOV. This re shoot is with the new 0.7 focal reducer for the 9.25 Edge. Three hours Ha added.
Imaging Camera: QSI640wsg
Imaging Scope: Celestron 9.25"Edge HD at f/7
Guide Camera: SX Lodestarx2
Mount: Avalon M-Uno Fast Reverse
Filters: Astrodon Gen II LRGB
Exposure: 90 min Lum, 1 minute subs unbinned, 45 min each RGB, 1 minute subs unbinned, 180 min
Ha, 30 min subs binx2
Processing: CCD Stack and PS CC
Date: Aug 4, 2018
Sky conditions: average seeing
Location: My front driveway. Morristown, NJ
Published in December, 2018 issue of Astronomy Magazine, p. 72.