Sharpless 103 / Cygnus Loop / Veil Nebula
Supernova Remnant in Cygnus
RA: 20h 45m 38s; Dec: 30° 42′ 30″; Dist: ~1470 ly
Cygnus Loop Supernova Remnant
This is a 4 panel mosaic captured over the summer and fall of 2015 and 2016.
Total Image Frames 1632
Total Image Time 96 hours
Per Panel Total
Filter Frames Exposure Frames Elapsed Time Start Date End Date
Lum 180 120 sec 720 24h 10-Jul-2015 01-Oct-2016
Red 60 120 sec 240 8h 17-Jul-2015 01-Oct-2016
Green 60 120 sec 240 8h 17-Jul-2015 01-Oct-2016
Blue 60 120 sec 240 8h 05-Aug-2015 30-Sep-2016
24 900 sec 96 24h 22-Jul-2015 01-Oct-2016
Oiii 24 900 sec 96 24h 22-Jul-2015 01-Oct-2016
Imaging Locations Ft McKavett TX
General Nathan Twining Observatory NM
Kenton OK - Okie-Tex Star Party
Magdalena NM
San Ysidro NM - White Ridge bicycle trails parking lot
Tijeras NM
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
Other Image Sizes
Full Resolution Image - email me
Half Resolution Image (6000x4500)
Large Image (3000x2250)
Medium Image (1200x900)
Small Image (600x450)

Imaging Notes
The nebula colors should be pretty close to correct. I found LEDs emitting at 502nm (Oiii is 500.7) and 657nm (Ha is 656.3) to use as color references during processing. My monitor is calibrated and I converted the images ICC profiles to sRGB for compatability with the common browsers.
I use Sequence Generator Pro for image capture. It makes collecting mosaic frames easy--automatically shifting between the mosaic panels and doing plate solves to put the camera back on the exact pixel and rotation night-after-night and location-after-location. I had 20 location changes during the year and a half of exposure capture.
Though the exposure information shows 1632 sub-frames over 96 hours, I really captured 2296 sub-frames accounting for 132 hours total exposure. I then chose the best 6 hours of luminance, Hα, and Oiii and the best 2 hours of red, green, and blue for each panel to make build the image.
The image is rotated 120° clockwise to fit the object mosaic and because I think it looks pretty good that way.

Objects in the Cygnus Loop
Annotated Image NGC 6992 NGC 6960

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