Combination of 15, 3 minute images, SBIG STL-1001E CCD.
20" f/6.8 cassegrain at prime focus.
Abell 25 is a moderately large, low surface brightness planetary nebula in Monoceros, about 0.5 degrees west of zeta monoceros. The magnitude is quoted as 15.1, but the light is spread out over and area about 3 arc minutes in diameter. Even after 45 minutes total exposure, the planetary is only weakly recorded.