Most of the people who love watching the night sky or enjoy bird watching use either
astronomical binoculars or
birding binoculars. You might be using some other kind of binoculars, but do you really know what
binoculars are?
Well,
binoculars are a combination of lenses and prisms. Lenses gather the light and focus the image, and prisms on the other hand, fold the light rays back and forth.
The first number in the
binoculars description describes you the magnification amount that this particular device has. And the second number reveals you the diameter of the objective lens in millimeters.
When buying
binoculars also remember that each of your eyes has its own focus point. It means that glasses will have a separate focus for both the right and the left lenses. So, less expensive glasses will only have a single focus.
Good luck in your search! And clear skies to you!