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C/2020 F3 (NEOWISE)


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About this observation
Nick James
Time of observation
07/07/2020 - 01:25
C/2020 F3 (NEOWISE)
Observing location
Chelmsford, UK
Canon EOS550D, 200mm, f/2.8 Lens
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To get a good NE horizon I cycled to a large field around 10 minutes away with all my gear in a rucksack. I had a Canon EOS550D with my trusty 200mm f/2.8L lens and a Star Adventurer drive on a small tripod. This is a stack of four 5.2s frames which have been dark subtracted and contrast stretched. The comet was a fabulous sight in 8x40 binoculars. A timelapse of all the frames taken on that morning is here.


Fossil Light's picture

That's a really beautiful time-lapse Nick.

Can you give us some details on the frames and processing for it?

Best wishes

nickjames's picture

Thanks Martin.

The source data is 232 frames of 5.2s each taken with a Canon EOS550D and a 200mm, f/2.8L lens on a Star Advenurer mount. In the original movie I used half size JPEG frames, stretched them and ran them together as a movie using ffmpeg. I have now replaced that with a movie based on the raw (CR2) frames. Each raw frame was converted to a 16-bit TIFF using dcraw with a suitable averaged dark frame. The TIFF frames were scaled to 50% and stretched using Imagemagick convert and then assembled into a movie using ffmpeg. All of those are command line tools which script nicely so I didn't have to do this on all 232 frames. The movie looks particularly nice when played on a big flat panel TV. 

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