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 Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...The Space and Astronomy Agora Human Powered Clock Drive For Various Latitudes Forum List | Follow Ups | Post Message | Back to Thread Topics | In Response ToPosted by Zac Helmberger on February 6, 2007 21:32:02 UTC

Dear Shashank,

If the clock drive is at the north pole with a latitude of 90 degrees north, the angle of the baseplate with respect to level ground would be zero degrees. In this case, you would not need a tripod! Just lay it down on perfectly level ground and start snapping pictures.

If the clockdrive was at the equator with a latitude of 0 degrees North, the clockdrive baseplate would be standing straight up at 90 degrees with respect to level ground. In this situation, the tripod would have to be nearly as tall as the baseplate and have enough clearance to tilt the mounting plate on the tripod to the full 90 degrees and enough clearance to accomodate the baseplate. If not, the baseplate could be chiselled or shaped so it won't bang into the tripod.

In your case, the latitude is 12.5 degrees north. So the angle of the baseplate with repsect to perfectly level ground would be 90-12.5 or 77.5 degrees. Thus, assuming the baseplate is 60" long, the tripod would have to be around 40 to 60 inches tall, depending on where you want to mount the tripod on the baseplate. The higher up on the baseplate you mount your tripod, the more stable it is.

Given that your tripod is about 24" tall, you could make a little table out of whatever is at hand, books, rocks, wood, etc. It doesn't even have to be a tripod that you mount the baseplate to. Just as long as you have some means to easily adjust the angle (altitude and azimuth) of the baseplate so you can see polaris inside the boresight tube. Tripods happen to be easy to use and let you easily position you head so you can look through the sight tube.

I'll be the first to admit that finding polaris in this narrow sight tube is a royal pain in the butt at my latitude. I suspect that it would be a lot easier near the north pole and near the equator! ;-)

Cheers,
Zachrey Helmberger
(I live in an earthship. A home that provides all of its utilities and comfort using nothing but the sunshine and rain that strikes the home)