"I made this image on June 10 (UT 00.35) at a very dark place in the mountains," Michael Jaeger in Austria posts to Spaceweather.com. "The comet was nearly 20° high. I used an 8-inch f/2.8 astrograph and CCD with a KAF 6303 chip."
The colors are real. Gas molecules of cyanogen (CN) and diatomic carbon (C2) in a comet's coma fluoresce green in sunlight. Ions of carbon monoxide (CO+) and carbon dioxide (CO2+) in the ion tail fluoresce blue. A comet's dust tail, on the other hand, simply reflects sunlight and is basically Sun-colored: pale yellow-white. This is clearly not a very dusty comet. Click image for larger view.