Scope: C8 f/2.8; Location:
Dos Picos Park, Ramona 6, Aug 2004; Camera: ToUcam SC3.
Exposure: 15 x 6 sec and 12 x 36 sec Luminance exposures with Baader IR Block Filter;
6 x 300 sec H-Alpha exposure, 12 x 12 sec RGB
Processing: All exposures captured in K3CCDTools. Alignment and stacking was done with Registax and saved as FITs. HA, and LRGB channels were co-registered in Astroart. Artificial flat fielding of each channel was done in Astroart as well as final scaling and rough color balance.
The two IR exposures were combined for star field with the shorter exposure used
to reduce star bloating (normal combine with mask). The Nebulosity was extracted
from HA and then combined with the IR for Luminance. HA and Red combined for red. These combinations were done in Photoshop. Final LRGB combine was done in Photoshop using Luminance Layering (or LLRGB). Color balance was done in Photoshop. SGBNR was used for background noise reduction.
This image is
NGC6823 and NGC 6820. They are hard to separate as distinct objects;
NGC6823 is the star cluster roughly centered in the image. NGC6820 is the
Nebula. This is a guided
image. The H-Alpha exposures help to bring out the contrast in the nebula. When
mixed in the red color channel for the color composite the Nebula comes out somewhat
monochromatic. Horizontal FOV is 30'