Sh2-129 in Cepheus

This Sharpless object is an extremely faint emission nebula which is located about 4 degrees west of the better-known large nebula IC 1396 in the constellation Cepheus. It has an interesting shape and surrounds a loose association of (slightly brighter) stars which are located slightly above the image's center. This asterism is probably connected to the nebula and provides the UV light which excites the hydrogen in the nebula and causes it to emit light.

IC 1396 and Surrounding Area, telelens photograph.
NGC 6946 and NGC 6939 and Surrounding Area, telelens photograph.
Sh2-129 in Cepheus in Hα, which is part of this image.

Exposure Data

Instruments: Hα: 4.9" f/3.8 Wright-Newtonian, RGB: 4.9" f/3.8 Wright-Newtonian + TMB 4.1" f/6.2 APO
Exposures: Hα: 30 x 10 min, RGB: various
Cameras: Hα: ATIK 383L+, RGB: Canon 350D with Baader UV-IR-Cut-Filter + QHY8 Pro
Dates: Hα: September 16, 2012, RGB: August 30, 2008 + September 16, 1012
Locations: Wallackhaus, Carinthia
Conditions: (September 15, 2012): SQM-L sky brightness 21.3 mag/arcsec², seeing 6/10, temperature +4°C, no wind, high humidity
Autoguider: Lacerta MGEN
Enhancement: Basic data reduction, combine, logarithmic curves, local contrast enhancement, noise filtering, star size reduction, Hα + RGB composition, color correction
Notes: A combination of the following images: Hα and color. Color images taken with the TMB refractor on a setup parallel to the Hα images were also added to the color rendition. Most CCD exposures were taken during my stay at the Großglockner-Hochalpenstraße in September 2012. See an Observation Report of this event (in German): Glockner 2012.