Jeremy's almost but not quite entirely moribund blog

Tuesday, July 26, 2005

Bad Astronomy

This morning before sunrise, I mounted my new camera on a tripod and attempted to take some pictures of planets and stars. It didn't work so well. The main thing I learned is that, even with a tripod, 15 seconds (the longest exposure time my digicam supports) is a long time for the camera to stay still. Even though I shot on a 2-second timer so that I wouldn't be touching the camera during the exposure, most of my shots were smeared. I suppose next time I'll (1) make sure the tripod is resting securely on the ground, (2) tighten all the little tripod nuts, and (3) use a 10-second countdown timer to give vibrations time to die down.

Anyhow, here are some photos that turned out okay.

Most of my shots of the Moon turned out overexposed. The photo above was exposed for 1/100 of a second.

This two-second exposure captures the Moon and Mars in the same frame. Of course the Moon had to be very overexposed in order for Mars to be visible. Mars is on the left side, about a third of the way up from the bottom.

And here's a 15-second exposure showing some stars. Well, maybe there are some stars there. Although the other photos are shown pretty much as they came out of the camera (save cropping, of course), this one has been extremely contrast-stretched to make the stars visible. So I can't be sure what are stars and what is just noise.

In retrospect, I probably should have bumped up the ISO level from the default 50 in order to photograph stars. Yeah, that'll increase noise too, but hopefully it will do that before the JPEG artifacts come in and thereby provide a better signal-to-noise ratio.

Anyhow, I wish I could tell you which stars those are, but I can't seem to match them up with anything. I think the camera was pointed west, for what that's worth.


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