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The development of building a telescope was greatly aided by the construction of the achromatic lens.
 
In 1733, the achromatic lens was invented by Chester Moore Hall, an English barrister. He began to make a telescope in the early 1700, but this was accomplished by combining a convex crown and a concave flint lens in [...]

An investigation into early telescopes makes for interesting reading. This instrument attracted considerable attention, and presently other makers were turning out Newtonian reflectors, following Hadley’s technique, which consisted of removing the spherical aberration as it was revealed by the extra-focal diffraction rings of a star image.
Hadley then turned his attention to a design by [...]

For those who decide to make telescopes it is a fascinating hobby. Telescopes are usually designed to perform particular kinds of work. In general, for visual work, low-ratio telescopes with their wide fields are useful for comet seeking, variable star work, and the like. The higher ratios are used in planetary study, double star [...]

In the past there has been considerable discussion by those inclined to make telescopes the relative merits of reflector and refractor. From the standpoint of professional astronomers, there is no serious competition between them, as each type supplements the other in a well-rounded observing program. An amateur who plans to make a telescope and to [...]

The history of the telescope makes for interesting reading from a theoretical perspective, but also from the perspective of someone interested in beginning to make a telescope. During the development of the telescope, practical experiments with reflectors had already begun in 1639, but it was not until 1663 that they gained any prominence.
The Gregorian [...]