Year of the Comet
Comet C/2011 L4 (PANSTARRS)

PANSTARRS information

Comet C/2012 S1 (ISON)

ISON information

Tony Hallas' Cosmic Imaging

Fixing oval stars

December 2012: Follow these steps to improve any unshapely stars infiltrating your images.
Contributed by Tony Hallas
Published: October 29, 2012
Tony Hallas
You’ve polar aligned carefully, collimated your telescope, and chosen an appropriate guide star. Yet, despite all these precautions, you’ve ended up with oval stars in one of your images. As long as the ovals are not too extreme, it’s possible to round them out in Photoshop if you follow these steps.

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