Another Summer Nebula (in the Northern Hemisphere), the Lagoon Nebula, M8 or NGC 6533, is a bright Nebula (one of the few visible to the naked eye) in the constellation of Sagittarius. The nebula contains the open cluster NGC 6530. It lies 4100 ly distant and has an apparent magnitude of 4.6. A wonderful target to photograph, it contains much detail and many fine structures. Here the hydrogen-alpha emission is colour-mapped to red and sulphur-II to yellow. The G´ photometric filter reveals the faint, wisp-like structures in the centre of the nebula. It was imaged from a dark sky region in northeastern Spain (40° North). As with all “Summer Nebula”, whilst the night-time temperatures are milder, making for a more pleasant photographic experience, the time available to collect data is limited. Working from a 40° North location provides additional data acquisition time compared to our home location (50° North).
Celestron RASA 11″
10Micron GM1000 HPS
SIGMA fp (monochrome) / SIGMA fp L (colour)
H-alpha / S-II ultra-fast narrowband filters,
G´ photometric filter
ca. 2.5 hrs, ISO 1600, F2.2, 620mm