Sunday slide 34

multiple exposure sequence of total lunar eclipse 2007
It shouldn’t be too hard to figure out why I decided on this one to feature this Sunday. This is not a solar eclipse, however – just a lunar one. The eclipse had started before the moon rose, so the sky still had some light in it while I was trying to capture a moon dimmed by atmospheric haze. Lunar eclipses always happen during the moon’s full phase, and at least during the warmer months the full moon rises during twilight. That light set the background color for all of the subsequent exposures, even though most of them were against an adequately dark sky.

Only a couple of digital cameras can do this without resorting to a photo editor, but film bodies could do multiple exposures on a single frame easily, and I occasionally played with the technique. The primary part of this was the use of a shutter ‘computer’ called an intervalometer, Canon’s TC-80N3, to be precise. This could be programmed to trip the shutter at specific intervals, or for specific lengths of time, and so on, which came in handy when doing a perfectly-spaced sequence as the moon traveled up the sky. I was using a Canon Elan IIe camera body, which only allowed a maximum of 9 exposures – unless you reset it before the sequence ended. The trickier part was deciding how long each exposure should be, judging from how much the moon was dimming as the eclipse progressed, and you can see the variation captured.

A better setting would have been nice, but it was hard enough to find a good field of view without traveling. It also would have been nice to carry the sequence right out of the frame, which is also challenging: the viewfinder was almost completely dark, so even seeing the edge was difficult, and finding the now-eclipsed moon glowing a very dim red and knowing how close it was to the frame edge defeated me. I should have kept snapping frames until very sure, but an easier technique would be to just crop the picture…

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