Saturday, June 22, 2013

Eclipse!

Tokyo, Japan (May 21, 2012)

My meeting wasn't supposed to start until later in the day, but I decided to get early to the University. My goal was to be on high grounds by 22:00 UT (that's 7AM local time) when a solar eclipse was set to start. This was my first time with a solar eclipse. Well, I have seen partial solar eclipses, but this was my first chance to witness the Moon transiting front and center in between Earth and the Sun. Given that the orbits of the Moon around the Earth, and of the Earth around the Sun, are slightly elliptical, the relative distance of the three objects when they are aligned is different each time. In some cases the Moon is a bit closer to Earth, and completely obscures the disk of the Sun: when that happens we have a total Solar eclipse. Sometimes instead the Moon is slightly farther away and its apparent size is not sufficient to completely block the light from the Sun: we have in this case an annular eclipse. What we had in May 2012 was an annular eclipse: not as impressive as a total eclipse, but still way cooler than a partial eclipse, when only a smudge of the Sun is covered by the Moon.

My plan was to try to photograph the event, but of course there were two problems. First of all you should never look directly to the Sun, eclipse or no, with your camera or with your naked eyes. The Sun is bright enough that you may damage your retina. To photograph the Sun you need a solar filter, and of course I didn't carry one. Secondly, to see the Sun you need a clear sky, and of course it was cloudy. What to do?

In the end one problem solved the other. The clouds were thick enough to provide a nice filter for the Sun, and at the same time not too thick to completely obscure it. In fact when I tried the first pictures came out a little over exposed, even with my lens all closed up at f/16, with the shortest 1/5000 exposure. To get an even smaller aperture I vignetted the lens with my hand, reducing the light entering the camera. And this is how I got the images posted above, with the Sun, the clouds and the Moon in between.

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