Refracting telescope gadgets have what is called the chromatic aberration problem. Because glass tends to refract any light differently in terms of wavelength, the telescope lens will break light coming in into varied colors which is a similar concept to the prism. Consequently, this effect limits the use of the refracting telescope because the overall effect would be a blurred image.
Chromatic aberration will be more pronounced and worse if you would attempt to assemble a telescope with a low focal ratio or large aperture. The ancient astronomers were aware of this and so they created lengthy focal ratio refractors with small aperture.
Christian Huygens, in the year 1656, was able to construct a refractor possessing a 2 to 4 inch aperture and a 23 foot focal length. This refracting telescope was able to magnify around a hundred times and had a view field of around 16-17 arc minutes. On the other hand, in order to gain better magnification, Johannes Hevelius did construct a 140 foot telescope in 1670.
Significant advancement of the refracting telescope happened in the invention of the achromatic objective. Although someone as prominent as Isaac Newton said that achromatic objectives are not possible, he was proven to be wrong when a British optical maker, John Dolland invented an achromatic lens using two types of glass which can provide better quality correction of color than the simple objectives.
The modern refracting telescopes now utilize the achromatic lens. Normally achromatic lens use two to three glass types having varied dispersions. This means that the light is spread into the spectrum differently. There is careful balance on the lens power, thereby reducing significantly the color effors. Ultimately the refracting telescopes that have large aperture and high focal lengths are much more feasible.
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