PanStarrs C/2011 L4 and Ced214 in Cepheus, April 30 - 2013

Setup: Borg 100ED f/6.4 refractor, DF-2 focusser, CFW8, ST10XE (2.1"/pixel), STV with efinder used for guiding, Takahashi EM-200 mount (image)

Acquisition: Panstarrs got 10x300 seconds through LRGB filters and Ced214 got 12x900 seconds through H-alpha and S-II filters. All done from my back yard in the suburbs of Copenhagen.

One March evening I noticed in my planetarium program that comet Panstarrs on April 30th would pass very close to the pretty - but faint - nebula Ced214 in Cepheus. In a bout of extreme optimism that this night would indeed be clear I took 6.5 hours of narrowband data one month in advance. It turned out that the weather was wonderful on April 30 so here I shot the comet for three hours with LRGB filters!

The comet motion was ~2"/minute (see animation below) so in order to get the stars and comet to be sharp I had a lot of processing to do. The subs were aligned on either the stars or the comet nucleus. The nucleus aligned images were 'minimum' combined so that stars moving behind the comet would be eliminated. The images aligned on the stars were sigma clipped combined and remnants of the comet were removed in Photoshop. These two images were then combined to yield a result were both the comet and the background appear sharp.


Here's my main page where you can see more of the pictures I have taken so far.


Comments greatly appreciated! (mikael@leif.org)