People often ask me â€œwhich telescopeâ€ toÂ buy,Â so I am going to help you here,
please click the blue text below for your reference information to print out.
These days there areÂ three main typesÂ of telescopes :-
- RefractorsÂ ~ Â Use lenses to collect and focus light.
- ReflectorsÂ ~ Â Collect light with a mirror.
- CassegrainsÂ ~ Â 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 :- Â To choose the right telescope?
Focal Length and Focal Ratio?
Telescopes, like cameras, have `f` numbers :-
- Focal Length Â – Â The distance between a lens or primary mirror and the point where the light rays Â it collect are brought into focus.
- Focal Ratio Â – Â The ratio of the focal length of a lens or primary mirror to its diameter. Â (A focal ratio of, say 8 is written as f/8.)
More information :- Â 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 :- Â 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 theÂ definitionÂ of the input and output parameters.
More Information about telescope types :- Â Advantages and Disadvantages
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