The star cluster M41 has a nice variety of star colors.
Details
2015-04-07 in backyard. Victoria BC
Conditions - clear and calm
Equipment - WO 105mm refractor operating at f/7 with Canon T3i (modified) on HEQ5 mount.
Exposure - 20- 30sec at ISO 3200 with 10 darks to match.
Processing in Images Plus and Photoshop. To help reduce atmospheric refraction effects the colors were separated, aligned and recombined.