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Total Lunar Eclipse
v@mp writes "I noticed a few posts today about space, which reminded me that there will be a total lunar eclipse in North America and Western Europe on Jan. 20. The moon will turn a deep red color for little over an hour around 8 p.m. on the west coast and 11 p.m. on the east coast. I'll see you all "under a blood red sky"--U2. "
Today is my birthday. Obviously, the moon is turning blood red to mark the dawn of a new era, the era in which I rise to rule mankind. Tonight is my night. Pray that you're on my good side...
-CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
Sicne the Moon is in Gemini, you're in a good situation because you can take longer exposures without getting trails. For a 50mm shot, my guess is anything under 15-20 sec should give you no trails (using a narrower-angle lens will decrease this tremendously!), but even when eclipsed the Moon might be still bright enough that you'll be using very short exposures. (Unfortunately my copy of Gordon's book is at the office, and I"m not!). Of course if you're using a telescope with tracking, it's not as much of an issue. I've only done still tripod imaging (which is fun all by itself). But be forewarned, even though the Moon looks HUGE, with a 50 mm lens, the actual lunar disk will only have a diameter of about 3 mm on the film!
Dickinson and Newton recommend for 400 speed film (I recommend SLIDE film over print film!) at f/8, an exposure time of 1/250 s at partial phases (after ingress), to 1/4 s during ingress near totality, to 1 to 10 seconds once totality starts, up to 100s for the deepest parts of the eclipse (and probably if the Moon is at perigee). Of course for exposures that are VERY long, you'll need to track the Moon to offset sidereal motion. But at a declination of 20 degrees North, as I said you can probably get up to 15 seconds without too much distortion (for a 50 mm lens).
Of course, in Boston, it's snowing.
But the next lunar eclipse visible in North America is less than a year away (Jan. 9, 2001).
Despite the fact that a solar eclipse and a lunar eclipse are completely different things, and staring at the full moon would not normally cause damage, it is important to remember that staring at an eclipse can damage your eyes.
More frighteningly, lunar eclipses emit deadly "lunar rays" which affect your brain and make you stupid enough to try to watch it through a welder's mask instead of binoculars.