IC 4628 Emission Nebula

clic for 30% size 1181 x 781 (425 kB)

clic here for 50% size 1968 x 1301 (1092 kB)

About this Image

The Nebula IC 4628, a beautiful, arc-like rim of nebulosity is situated in the far southern sky in the tail of Scorpius (from Zeta- to Mu-Scorpii). It is quite faint and has often been overlooked because of it, even by southern observers. However, it is in a rich region, reflected in the number of names associated with the objects in the field illustrated here. There is a large scattered star cluster, Collinder 316 which extends over the center of this picture. The nebula itself is also known as Gum 56, after the Australian Colin Gum who catalogued emission nebulae in the southern sky using wide field photography. The huge extent of this nebulosity can be seen in the wide field image here.
The distance to this nebulae is approx. 5300 light years. North is up-right.

Below you find a H-alpha crop on IC4628 in 35/70% size.

clic for 70% size 1222 x 1142 (387 kB)

Technical Details


105mm TMB refractor with flattener at f/6.5

Mount AP-400 GEM
Camera SBIG STL-11000M at -20C, internal filter wheel
Filters Astronomik H-alpha (15 nm) + RGB
Date Aug 12, 2004.
Location Hakos/Namibia
Sky Conditions mag 6.5, high transparency, temperature 12 C,
Exposure Ha = 80 minutes (10-minute sub-exposures),
RGB= 15:15:15 min (5-minute sub-exposures)
Processing Image aquisition in Maxim DL 4.0; Image calibration, aligning, mean stacking, DDP and color synthesis in ImagesPlus;
Photoshop: H-alpha blended to red and L channel; cropped, Noise reduction by Neatimage;