Horsehead star trails
This image is a combination of an image of the Horsehead region in Orion and some star trails coming from it. The startrails were obtained from frames that were exposed after the tracking mount stopped. I processed the image of the Horsehead first and added the startrails next.
The color of the stars shows up nicely in the startrails.
Modified T1i camera with 300mm lens on Astrotrac mount
94 - 60 sec light frames at ISO 400 amd f/4 with 31 darks and 8 flats for the image of the Horsehead.
31 - matching star trail frames with the mount stopped.
Processing in Images Plus, Photoshop and Startrails.de