vdBH 81

STARS EMBEDDED IN NEBULOSITY - ARA

 (ra: 17:00 1s / dec - 51º01' ")

JULY 2012, Archicampo, Doyle Provincia de Buenos Aires,

Argentina

DATA FROM vdBH 81 CATALOGUE

TYPE: Type II stars are outside the nebulosity

BRIGHTNESS: Br (Bright)

DIAMETER OF THE BLUE NEBULOSITY: D (B) 6.4 arc minutes

NEBULOSITY COLOR: mB (moderately Blue)

ABSORPTION FIELD: Str (strong)

OBJECT DESCRIPTION AND IMAGE SESSION

vdBH stands for astronomers Sydney van der Bergh and William Herbst. In 1966 Sydney van der Bergh published a catalogue of stars embedded with reflection nebulosity for objects above Dec - 33. In 1975 and with the participation of William Herbst, he covered the Southern Milky way using the Curtis Schmidt Telescope of the Cerro Tololo Observatory.

The object we are showing now is the number 81 out of a list of 136. We understand there are no RGB pictures of vdBH 81, so while imaging we didn't know what to expect. Only when the RGB channels were combines there blue faint glow showed up. The stars group is not located within the nebulosity but outside. The surface brightness was catalogued as Br (bright) however I need to bin 2x2 all channels to bring the faint glow of the nebula. Probably because the sky quality.

Thanks to Sakib Rasool for providing information on this object

The vdBH Catalogue of Southern Stars Embedded in Nebulosity could be found here.

IMAGE INFORMATION

SCOPE: Celestron SCT 8" Starizona Corrector @ f8 (1600 mm FL)

MOUNT: Sky Watcher NEQ6

SKY CONDITIONS: Rural Skies - seeing good - transparency good

CAMERAS: QSI 583 WS -10Cº

FILTERS: Baader 31 mm LRGB, 

EXPOSURES: LRGB (60,30,30,30) all bin 2x2

GUIDING: William Optics ZenithStar 66 f6. Starlight Xpress Lodestar Camera. PHD Guiding 

PROCESSING: Images Plus, NASA Photoshop Fits Liberator, Photoshop CS