People often ask me “which telescope” to buy, so I am going to help you here,
please click the blue text below for your reference information to print out.
These days there are three main types of telescopes :-
- Refractors ~ Use lenses to collect and focus light.
- Reflectors ~ Collect light with a mirror.
- Cassegrains ~ Use a combination of mirrors and lenses.
To choose the right telescope?
Telescopes are judged not by their magnification but by their aperture.
- More information :- To choose the right telescope?
Focal Length and Focal Ratio?
Telescopes, like cameras, have `f` numbers :-
- Focal Length – The distance between a lens or primary mirror and the point where the light rays it collect are brought into focus.
- Focal Ratio – The ratio of the focal length of a lens or primary mirror to its diameter. (A focal ratio of, say 8 is written as f/8.)
More information :- Focal Length and Focal Ratio?
The magnification of a telescope depends on the eyepiece used.
Telescopes usually come with a selection of eyepieces that offer low, medium and high powers.
- More information :- Magnification
- The eyepiece calculator reveals the observing potential of your telescope with eyepieces, it accepts basic information about your telescope and displays results for all eyepieces.
- Refer to the diagram and tables below for the definition of the input and output parameters.
More Information about telescope types :- Advantages and Disadvantages
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