How many images of the Ring Nebula does one need? I figure at least one for each telescope available, and perhaps one for each camera with each telescope.
Actually, I was shooting something else which set behind the trees around 4 am. Rather than shut down for the night, I slewed to M57 for a short session.
There is something delightful about shooting relatively bright objects. It's so easy to get a good signal-to-noise ratio. Besides, M57 is so colorful! Why not shoot it often?
Telescope: Orion 254mm f/4.7 Newtonian and Baader MPCC
Camera and Exposure: SXVF-H9C (14x180"), Alnitak Flatman flats
Filter: Astronomik CLS
Guiding: SX Lodestar and SX SFW+OAG
Mount: Takahashi NJP
Software: Nebulosity, Photoshop CS3
Location: The Woodlands, TX
While waiting for clouds to go away in March of this year, I pulled some data from the Hubble Legacy archive. Here's a much more detailed image of the Ring Nebula from the Hubble Space Telescope, thanks to those who maintain the archive and the creators of FITS Liberator, version 2.