Sorry for the delay, was busy somewhere else.
Your telescope seems similar in size to the first I made, 25 years ago...
Lets begin from the start.
There are three main kinds of telescopes:
- Refractors. They are made with lenses
- Reflectors. They are made with mirrors
- Catadioptrics. They are made with a combination of mirrors and lenses.
Source:
http://www.skyandtelescope.com/astronom ... elescopes/
Covers, as Dennis has explained, are used to keep dust and dirt out of the telescope when it is not being used, and have to be taken off so the light can enter the telescope as shown in the diagrams above.
The main defining spec for a telescope is the aperture. It defines light gathering ability and from it we can guess how good and detailed an image it could be showing.
After the aperture is the focal length, it can help us to have an idea about the apparent size of the images we can obtain.
As for the phot you posted, the aperture of the telescope is 76 mm or roughly 3", its focal length is 700 mm (roughly 27.5"), dividing the focal length by the aperture (as if it were a camera objective) results in a f/9.2.
The mount of the telescope in the image is an Altazimuthal, which means that you can move where it is pointing to from side to side (Azimuth) and up to down (Altitude). The idea of the rod in one side is to hold the telescope in position. ¿See the cross handle screws? they are used to release or hold the side rod and the support fork.
You may have noted that in the rod extreme that is attached to the telescope that it also has a knob, it can be turned to move slowly the altitude that the telescope points to.
The tube contraption that protudes to the side, that has two knobs and where you can place the eyepieces or oculars is called focuser, by turning the knobs you can adjust the focus if the eyepieces don't share the same focal point along their tube.
The small telescope to the side of the focuser is called Finderscope. The idea is that in the inside of the finderscope there is a reticle (merely a cross made of two thin copper wires) and is mounted in a way that you can align it with the view of the main telescope (careful with those crews, they are intended to fix the position of the finder, not to alter it), so that to find something in the sky, you center it in the finderscope, then observe it through the eyepiece of the main telescope and has to be centered.
I found a series of videos that can help you.
https://www.youtube.com/watch?v=goL3K_xQzbE
https://www.youtube.com/watch?v=gpnB5w_gZsI
https://www.youtube.com/watch?v=DODk3cJam68
https://www.youtube.com/watch?v=9oALhSq0hoY
https://www.youtube.com/watch?v=dpF1_Q5yPsk
https://www.youtube.com/watch?v=waPj5AkXirs
Please ask whatever you didn't understand.
