Aligning sun images using Python

Fix it in post. It’s a common phrase in photography and one which is widely recognised as landing you in hot water if you’re not careful. Fix it in post-production, fix it after the fact. “Hm, I’ll just fix that in post.”

Well when I spent a day taking a few hundred photos of Venus crossing the sun last year with the intention of creating a time-lapse but without a tracking system, “fix it post” was my mantra by necessity. For 7 hours I followed the sun across the sky just by nudging my camera mount this way or that. As a result the sun was in a different place in every photo. The fact I wasn’t standing on the equator at the time meant it rotated too.

Transit of Venus 2012 time-lapse

Venus passed in front of the sun on 6th June 2012, and all the while I was happily photographing it from tropical North Queensland.  Here is the time-lapse of all the photos I took throughout the day.  The music is by Kevin Macleod – thanks Kevin!

Photographing the Transit of Venus 2012

The transit of Venus 2012: Six frames at equal intervals throughout the transit, starting here with second contact (top left), then along each row until third contact (bottom right). The sun is shown with its south pole at the top, and in sunny false colour of course :)

On 6 June 2012, Venus passed directly between Earth and the Sun. This ‘transit’ won’t happen again until 2117, so I’m happy that I got some photos of it! I was asked to write a few words on my experience for the August 2012 issue of the AAO Observer newsletter, so in lieu of rehashing the same story, here’s what I wrote for the article.