Found in space. The Astrometry bot on Flickr (which detects which part of the night sky is contained within your photo and adds notes to some of the more interesting stars) is the most delightful use of the Flickr API I’ve ever seen. This interview provides some background, including a link to a paper on the “scale and rotation invariant hashing algorithm” that is used to build the index.
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The astrometry.net bot is annotating pictures in the Astronomy Photographer of the Year group too, where it's also machine-tagging photos. I wrote a rough guide to the astro: tags to go along with the pool. It'll be cool to see what sort of things could be done with the machine tags.
Jim O'Donnell - 19th February 2009 03:10 - #
phl - 20th February 2009 11:43 - #
I wonder how well it copes with barrel/pincushion distortion, which isn't unknown on consumer-grade telephoto lenses at the long end. I guess you could scrape the lens info from the EXIF and compare with a database of known lens distortion characteristics ...
phl - 20th February 2009 11:49 - #
I don't think it corrects for barrel distortion. Here's a wide field with distortion and you can see the notes for Ursa Major don't precisely match the positions of the stars in the photo. Still very impressive.
Jim O'Donnell - 20th February 2009 22:19 - #