Apochromatic refractors use two lenses shaped like an achromatic refractors except they are made of two different types of glass which allows them to focus all colors of light at the same spot. These telescopes give without a doubt, the sharpest views an d the highest contrast. Another type of telescope is the Newtonian reflector. These telescopes give you the most aperture for the dollar. A Newtonian reflector uses mirrors to reflect and focus light on a converged point.
Newtonian reflectors give very sharp views with almost as much contrast as an achromatic reflector.
These telescopes are good for any astronomical use you may have for them. A reflector is the most cost effective telescope you can buy. The last type of telescope is the catadrioptic. The Schmitt Cassegrain telescope combines a refractor and a reflector in one package. The resulting telescope is extremely portable, compact and user friendly.