The California Nebula is an emission area located in constellation Perseus. It appears to resemble outlines of State of California on long exposure photographs, like this one. It has a very low surface brightness and it's very difficult to observe visually. Distance from my hometown Oulu, Finland, is about 1000 light years.
Technical details
Processing workflow
Image acquisition, MaxiDL v5.07.
Stacked and calibrated in CCDStack2.
Deconvolution with a CCDStack2 Positive Constraint, 33 iterations, added at 50% weight
Color combine in PS CS3
Levels and curves in PS CS3.
Imaging optics
Tokina AT-x 300mm f2.8 camera lens
Mount
10-micron 1000
Cameras, filters and guiding
Imaging camera Apogee Alta U16 and Apogee seven slot filter wheel
Guider camera, Lodestar x 2 and an old spotting scope of Meade LX200
Astrodon filters,
5nm H-alpha 3nm S-II and 3nm O-III
Total exposure time
H-alpha, 7 x 1200 s, binned 1x1 = 2 h 20 min.
O-III, 2x 1200 s, binned 2x2 = 40 min==
Copyright: J-p Metsavainio