Telescope Buying Guide

Mystic Swordman Lv4 asked:


Can anyone describe the refracting telescope to me?
I need information on the refracting telescope for my school project. Please include a diagram (labeled) and description of how it works. Also, explain its uses in the world, and how are they useful. Finally, include references so I can refer to them later.

bigK asked:


so what’s the difference between the objective lens of a microscope and a telescope. for each do you want the object in front or behind each lens. which is a bigger focal length better for, and what kind of image is formed for each?

Dream asked:


I am doing a project and i need help. If u cover 1/2 the lens of a telescope the image u are viewing would obtain to be dimmer but why?

Dream asked:


I am doing a project and i need help. If u cover 1/2 the lens of a telescope the image u are viewing would obtain to be dimmer but why?

MH asked:


I tried to make a homemade telescope using an eyepiece and a magnifying glass. It magnified the image but the produced image is so blurred and inverted as well. Any ideas how can i fix it as simply as possible ?

Free2b asked:


a.The 8-meter telescope has 4 times the light-collecting area of the 2-meter telescope.
b.The 8-meter telescope has 16 times the light-collecting area of the 2-meter telescope.
c.The 8-meter telescope has 8 times the light-collecting area of the 2-meter telescope.
d.The answer cannot be determined from the information given in the question.

Jason N asked:


A typical telescope used by amateur astronomers has a mirror 20cm in diameter. With such a telescope, fine details can be seen on the surface of the sun.
Explain why a radio telescope would have to be much larger to “see”comparable details on the sun.
I think this may be explained by the formula sinx=1.22 wavelength/diameter.

so, the smaller diameter will give the telescope an advantage to see the objects. But why bother to build a large radio telescope?

Song P asked:


because you can use it to observe distant objects here on earth. What is the main reason why you wouldn’t want to use an astronomical telescope for watching birds?

Vincent L asked:


I can’t find any good scope seller or an optical shop in our place that sells customizable mirror. I’m planning to buy a magnifying mirror and use it as a reflecting scope’s primary mirror. I’ve heard that the focal length might be short. How short is an average focal length of a magnifying mirror? Is it too short to be used in a telescope or passable as an average quality scope mirror? I haven’t bought one and measured it.

vanessa_jj asked:


A researcher is trying to shoot a tranquilizer dart at a 2.2-m-tall rhino that is 160m away. Its angular size as seen through the rifle telescope is 9.9 degrees.
What is the magnification of the telescope?