Bibliography
Here you will find some recommended reading to learn more about optics and telescopes.
James G. Baker's groundbreaking article in Applied Optics entitled Planetary Telescopes is available from this website (note there is a fee of $20.00 to download the article, although it may be available at University libraries). The article discusses in detail why refractors are the very best telescopes of any type. Thomas Back recommends this article for anyone who wants to learn more about the history of apochromatic refractors, why they perform as good as they do, the many different design types of apochromatic refractors (for planetary use), what the requirements are for different levels of refractor correction, and what they mean.