NGC 3918
The Blue Planetary

Combination of 2, 3 minute exposures, SBIG ST-4 CCD.
300mm f/6 newtonian at prime focus.

NGC 3918 is a small but bright planetary nebula situated in Centaurus, about 10 degrees west of gamma crucis. It is a favourite amongst southern hemisphere observers because of its very strong blue colour.

Combination of 5, 3 minute exposures unfiltered
5, 3 minute exposures using red and green filters, and 6, 3 minute exposures using an blue filter.
SBIG ST-8XE CCD. 300mm f/6 newtonian telescope at prime focus.

In an 8" telescope using high magnification, the nebula appears as a uniform, circular patch of light with a very destinct blue colour.