The shots were made just for testing purpose! 3 min. x 8 frames at ISO3200 for H-alpha (poorman's H-alpha --- Lumicon H-alpha + IDAS LPF P2) 2 min. x 3 frames (IDAS only) same Sigma zomm (150-500mm) at 500mm. Regardng H-alpha and RGB composite, please refer to the method of 80/20/20 by Neil Heacock. http://tinyurl.com/7jqxzly