Newtonian Telescope - Advantages of The Newtonian Design

Advantages of The Newtonian Design

• They are free of chromatic aberration found in refracting telescopes.
• Newtonian telescopes are usually less expensive for any given objective diameter (or aperture) than comparable quality telescopes of other types.
• Since there is only one surface that needs to be ground and polished into a complex shape, overall fabrication is much simpler than other telescope designs (Gregorians, cassegrains, and early refractors had two surfaces that need figuring. Later achromatic refractor objectives had four surfaces that have to be figured).
• A short focal ratio can be more easily obtained, leading to wider field of view.
• The eyepiece is located at the top end of the telescope. Combined with short f-ratios this can allow for a much more compact mounting system, reducing cost and adding to portability.