Two-panel HaRGB mosaic, Horsehead Nebula region in Orion, including:

NGC2024 Flame Nebula (low center left)
Barnard 33 Horsehead Nebula (low center right)
IC434 Emission Nebula (right, behind Horsehead)
Sigma Orionis, SAO 132406, the source of light for IC434 (far upper right)
NGC2023 Nebula (low left of Horsehead, not much Ha content)
Alnitak SAO 132444, eastern-most star in Orion's belt (bright star left of center)
IC432 (up and left from Flame)

For each of two luminance panels:
Ha: 40 x 120 seconds

RGB was shot using a higher effective focal length and required three panels:
R: 29 x 120 seconds
G: 29 x 120 seconds
B: 29 x 120 seconds

Ha Luminance, with 60% opacity to bring out RGB star field and reflection nebulae.

Imaged through Celestron 80ED at f3.8 with Antares 0.5x focal reducer. Ha frames taken with DSI Pro II at f3.8. RGB frames taken with DSI II-Color at f4.5. Guided with the non-imaging DSI through 8 inch LX90 at f6.3. Schuler 9nm Ha filter, Meade RGB filters.