I'm confused about telescopes

[Celestial]

:sad: Hello,

Is there a website that detials the differences between telescopes with difinitions of some terms, for example : differences between the reflector and refractor scope, which one is better? what is the EQ mount or scope? and how do I use it? what does the 'mm' mean in e.g a 50mm scope ? what is the RA motor? and how is it used?

My scope is 900-130EQ what does that mean? I just set it up and start viewing without understanding the concept of the it or how it works.

Don't worry about answering this heap of questions, I would however be grateful if one of you guys got a link to a webiste that has the answers.

[turbo-1]

Go here. Start at the beginner's section and have fun.

http://www.astronomyforum.net/forum.html

[Wolverine]

There's also a nice section here (http://skyandtelescope.com/howto/scopes/) which will address your questions.

[aurora]

Here's a few answers in case the linked sites aren't clear.


differences between the reflector and refractor scope, which one is better? what is the EQ mount or scope? and how do I use it? what does the 'mm' mean in e.g a 50mm scope ? what is the RA motor? and how is it used?

My scope is 900-130EQ what does that mean? I just set it up and start viewing without understanding the concept of the it or how it works.


Reflector = uses mirrors. Refractor = uses lenses. There is no best type, it depends on what you are going to use it for. The links probably get into that discussion.

EQ is the mount, it means the mount can track an object when the Earth rotates, by being an equatorial mount. The mount also has to be properly aligned for the tracking to work.

mm is millimeters. A 50mm scope has a primary lense that is 50mm in diameter (very small).

RA = right ascension. An RA motor would move one of the axis of the mount, the right ascension. This is the one that would allow the scope to track an object, if the scope is aligned.

I assume that a scope that says 900-130EQ would be a scope that has a 900mm focal length, a 130mm aperture, and is on an equatorial mount.

Well, that's a start. Hope that helps.

[JohnW]

A few quick answers to your questions (but read the websites turbo1 and Wolverine provided):
differences between the reflector and refractor scope, which one is better?
A reflector uses a curved mirror to focus the light. A refractor uses lenses. Neither is "better", but each is good at different things. Reflectors are easier to manufacture, so a good reflector of a given size will be cheaper than a good refractor. But a good refractor will give better images than a good reflector of the same size. In other words, you'll see more with a reflector, and see fewer things better with a refractor.

There are other advantages and disadvantages of each design, (portability, ease of set-up, etc.) Your needs will determine how inmportant they are to you.

what is the EQ mount or scope? and how do I use it?
An equatorial (EQ) mount has an axis of rotation which points north (or south in the southern hemisphere). This makes it easy to track an object once you've found it -just rotate the scope around this axis and you shouldn't need to adjust anything else. The disadvantages of these mounts is that they are heavy, and can be difficult to set up the first few times.

what does the 'mm' mean in e.g a 50mm scope ?
It's the aperture, or diameter of the objective (the main mirror or lens).

what is the RA motor? and how is it used?
You can motorise the right ascension axis (RA - equivalent to longitude on a globe) of an equatorial mount so that your telescope will slowly move across the sky. This means the tracking I described above automatic. To use it, you will need to align your mount accurately. And check your manual - sometimes these motors need to be disengaged before you can find the next object.

My scope is 900-130EQ what does that mean?
900mm focal length, 130mm aperture, equatorial mount.

[Celestial]

Thank you very much guys for the links, I'm very grateful, they seem to contain valuable information which should not be missed by someone like me!
aurora and JohnW thank you very much for taking the time, that was kind of you.

[Dave Mitsky]

Here are more sites to further edify (or confuse) you:

http://www.astronomy.com/asy/default.aspx?c=ss&id=9

http://www.scopereviews.com/begin.html

http://stupendous.rit.edu/richmond/answers/telescope.html

http://www.r-clarke.org.uk/starting_astro.htm

http://www.celestron.com/education/tel4ast.htm

http://www.astronomics.com/main/category.asp/catalog_name/Astronomics/category_name/How%20to%20pick%20a%20telescope/Page/1

http://www.telescope.com/content/lea...avIDs=19,22,29

http://www.floridastars.org/telescop.html