Saturday, January 1, 2011

Total Lunar Eclipse

On December 21st I watched the total lunar eclipse from the driveway of my house. The weather forecast had been for partly cloudy, but the sky cleared about 1-1/2 hours before it began. At midnight the temperature was barely above freezing.

I tried to photograph it through a telescope, but you can see that was not very successful. What went wrong? Well, like what can happen for public speaking, I was just winging it. On short notice I grabbed some pieces that had worked for me once before on a warm day. But, I didn’t rehearse or plan ahead, so I did not see what should have been there but wasn’t. Doesn't that sound familiar?

When you point a camera at the moon you find that it looks pretty small. I magnified it about fifty times with a spotting telescope mounted on a tripod (Manfrotto 190 with #410 Junior geared head). My camera had a photo eyepiece originally meant for a microscope, with an aluminum adapter to make it fit on the telescope. The magnified image kept moving out of view though.

As shown above, my digital camera is a Nikon Coolpix E995 that fits into a coat pocket. The body is in two pieces that can swivel. The left side contains a recessed zoom lens and optical viewfinder. The right side has the controls and an LCD display. Usually I keep the camera set for both auto-focus and auto-exposure.

Less than what is recorded shows on the optical viewfinder, so I normally check my framing on the LCD display, and zoom in until I like the image. Having the LCD display on runs down the battery fairly quickly, so normally I also set the camera to automatically shut off after a minute (and carry a spare battery). The LCD display can be turned off and on by pushing the little MONITOR button, but that’s not easy to do in the dark with gloves on.

The telescope gets focused by turning a ring on the front. Auto-focus on the camera doesn’t help. I set the camera to focus far-away by pushing the button at the lower left (with the mountain symbol). To avoid vibration from pushing the shutter button I had to use a plug-in remote control, as shown above. (The built-in timer only works together with the close-up setting, which is the flower symbol). After midnight I gave up on taking pictures, and just watched through the regular telescope eyepiece.

What did I forget? I have an AC adapter for the camera, and it would have been easy to run an extension cord out from the garage. Then I could have left the LCD display on, and easily kept the moon centered just by occasionally adjusting the pan and tilt knobs on the tripod.

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