Antares & Rho Ophiuchus Region

Object Data: The region around Antares (Scorpius) is one of the most amazing and beautiful in the entire night sky. It contains a complex mix of emission nebulae, reflection nebulae, dust lanes which obscure the background stars, and star clusters. The giant yellow star Antares dominates the central region of this photo and it is surrounded by an emission nebula to the south and a very rare and beautiful yellow reflection nebula to the north. To the north of the photo is the tri-star Rho Ophiuchus which is surrounded by a large blue reflection nebula called IC 4604. The dark dust lanes of the Milky Way can be seen spiralling eastwards from this region. The small bright reflection nebula to the north of Antares is IC 4605, reflecting the light from the magnitude 4.5 star 22 Scorpious. To the right of the photo is the bright star Sigma Scorpious surrounded by the bright emission nebula Sh2-9. To the south east of this can be seen the bright globular cluster M4. Finally to the north west of Antares is the small globular cluster NGC 6144. Date: 23/06/06 Location: Southern France Conditions: Calm, no dew. Transparency=8, Seeing=6 Optics: Nikon 180mm f/2.8 EDF lens (working at f/4) piggybacked on an AP 155 EDF f/7 refractor which acted as the guidescope. Mount: AP 900 GTO on Portable Pier Autoguiding: SBIG ST-8E tracking AP 155 EDF refractor Camera: Canon 20D ISO 400 shutter control via computer Exposure: 11x 5 minutes Processing: Acquisition and initial processing by Images Plus - final processing in Photoshop. Notes: This is an interim attempt while awaiting arrival of the STL-11K - a poor result owing to the integral IR filter of the 20D effectively extinguishing all Ha response. The 20D was purchased primarily for landscape photography and I did not attempt to modify it for astrophotography.