Telescopes

Archive for July, 2009

I just want something that is capable of seeing the other planets. Jupiter and Saturn are the two plants that I mainly want to see.

How much am I looking at for a telescope that is capable of this?

Thank you.

Ummm I suggest you go and get yourself exactly what you want… a Telescope I have a JASON and it works great for me. Less than $200 I think, good luck.

i want to view the planets jovian and terrestial in the summer thats when i have been told they would be visible. how strong should the eye piece magnification should be? could someone please tell me…

For planetary viewing you”ll want to use a medium to high power, unfortunately the atmosphere is rarely stable enough to get away with magnifications over 200x. I have gotten some great views of Jupiter and Saturn at around 150x

to figure the power of a telescope/eyepiece combination you take your telescope’s focal length over the eyepiece’s focal length. But since you’re wanting to know what eyepiece you should get you need to divide you Telescope’s focal length by the power you’re wanting, for example let’s say your scope has a focal length of 700mm and you’re wanting an eyepiece to give you 150x magnification, you’d take 700/15 which gives you 4.6. It’s pretty unlikely that you’ll get a number that exactly matches an available eyepiece’s focal length, so just get the closest match you can find.. If you get one that has a slightly lower focal length you’ll have a bit more power and if you go with a larger one you’ll have a bit less power.

Refractors, Telescopes that use only lenses, excel at terrestrial viewing, lunar viewing, planetary viewing, star cluster viewing, and astrophotograpy of stars, star clusters, planets, and the moon.

They are especially desirable for observing stars because they have no central obstruction held in place by support bars, so stars appear as perfect dots and not as "stars" with what are known as diffraction spikes. They are desirable for planetary and lunar viewing because they offer high contrast images. They are also more rugged than other types of telescopes.

The full benefits of a refractor can only be had if it’s apochromatic though. Good refractors are very expensive.

There are many different types of cassegrains, however, they all share in common a folded design, and a central obstruction held in place by a glass plate at the front of the telescope. Different cassegrains are ideal for different things, but in general, they have long focal lengths so also do very well on planetary viewing, and again stars will have no diffraction spikes when viewed with them.

Cassegrains are an economical alternative to refractors, and like refractors, can easily be made large enough for deep space viewing. Their folded design also means they are more compact that other types of telescopes.