ISON outburst

ISON observers had begun to report an “outburst” that might have increased  the comet’s brightness by up to two orders of magnitude.  While it is advisable to temper one’s enthusiasm with the knowledge that Cumbrian skies don’t always play ball with astrophotography, my trusty forecaster App indicated that there might be a short window this morning between ISON’s rising at 04:04 and the development of an overcast dawn from twilight at 05:34.

Alarm set for 03:30, swap texts with Stuart Atkinson at 03:40, load the kit in the car and off we go towards Farleton, east of Kendal, to get away from urban lights.

Remember that Cumbrian skies don’t play ball?  Well, there was a stubborn bank of low cloud on the eastern horizon (Stuart’s wider angle photos give a much better context of our session) but suddenly, in the gaps…

Comet C/2012 S1 (ISON) 300mm f/5.6, ISO 800, 30 sec. Single frame.

Comet C/2012 S1 (ISON)
300mm f/5.6, ISO 800, 30 sec.
Single frame.

Amazing for a single shot, compared with the stack of 20 frames from the previous outing.  Note also that this is 30 seconds at ISO 800 whereas the previous outing was 20 x 60 seconds at ISO 1600.  I have stretched the histogram in PixInsight, and rebalanced the colour to get rid of the more extreme red glow in the clouds.

The 12MP frame can even stand cropping to enlarge it to 6x the original…

Comet C/2012 S1 (ISON) 300mm f/5.6, ISO 800, 30 sec. Single frame, cropped.

Comet C/2012 S1 (ISON)
300mm f/5.6, ISO 800, 30 sec.
Single frame, cropped.

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