Info on telescopes

[barbarhow]

I am looking to buy a telescope for DH for his birthday and am hoping someone knows something about them. My usual source-Consumer Reports-has nothing on them and I am at a loss. There always seems to be someone here who knows something about everything. (It would be primarily used for astronomy purposes.) TIA
Barbara-mom to Jack 3/27/03

[kurosch]

The single most important factor to consider for astonomical telescopes is light-gathering power. This is directly proportional to the aperture, or size of the tube. The larger the diameter of the tube, the more light is gathered. Buy the largest diameter scope you can afford.

The next choice is refractor vs. reflector. Refractors use two lenses, basically one at each end, to magnify the image. Reflectors have a large spherical mirror at the back end which focuses the light onto a smaller mirror which then reflects the image into an eyepiece. Generally speaking, larger telescopes are almost universally reflectors because it's much easier to make a larger diameter mirror than a large lens (any flaws in the lens or mirror will distort the image). Reflectors are also much cheaper and lighter for their size.

Reflectors come in two main styles, Equatorial mounts and Dobsonian. Equatorial mounts have stands which alighn them with the Earth's axis. This allows for easy adjustments to specific coordinates of the sky, and many have clock motors in them to keep the telescope pointed at the same object as the Earth rotates. Dobsonians are basically long tubes that sit on a very basic stand that does not move and is not aligned with the axis or equator of the Earth. They are therefore more difficult to point at something specific, and don't automatically track objects, but you can usually get a larger aperture and tube for the same money because you're not paying for all the fancy stuff.

Many equatorial mounted telescopes nowadays come with computers that will automatically find objects in the sky once they are calibrated to a known coordinate, but I think that is a waste of money because part of the fun is homing in on a star or galalxy or whatever yourself.

Bottom line, get the largest diameter reflector you can afford. You can always adjust the magnification a certain amount by getting different eyepieces later.

The big names in telescopes are Meade and Celestron. You probably can't go wrong with either of those.

Let me know if you have any other questions.

[stillplayswithbarbies]

We have a big white one. It's pretty and you can see the moon. LOL Obviously I am not the expert in the family but I'll ask hubby about it. We used it to look at the eclipse the other night.

...Karen
Jacob Nathaniel Feb 91
Logan Elizabeth Mar 03

[Meatball Mommie]

I too know nothing about them, but my SIL bought one for my BIL recently, so I will ask her the specifics. I do know it'a Meade (the box was in our garage for a while :) I'll let you know what she says about the one she bought.

[Meatball Mommie]

OK, I asked my SIL. She said she got it from Discovery Channel .com They apparently have info on their website for prospective buyers. She said to click on "telescope buying guide". Hope that helps!