These classic refracting telescopes provide contrasty and sharp images, and are recommended for lunar, planetary observations and for double stars. Using smaller magnifications they provide excellent views of brighter deepsky objects or starfields in the Milky Way. The Fraunhofer objective lens provide excellent colour correction. No collimation is needed. Besides astronomical observations they can be used for terrestial work as well with an erecting eyepiece.
Newtonian telescopes are the cheapest ones in a given aperture. No colour aberration but the image is less contrasty because of the central obstruction caused by the secondary mirror. The fast ones are recommended for deep-sky observations and astrophotography, but can also be used for planetary observations. Somewhat more compact telescopes than the traditional refractors but require a precise alignment of the optical elements. With some limitation they can be used for daytime observations as well. General purpose telescopes for both beginners and advanced amateur astronomers.
The Dobson mounts are very popular, usually the larger aperture Newton telescopes are used with Dobsonian mounts. Dobsonian mounts are very robust and steady and are also affordable for larger scopes as well. The telescope can be mounted easilty and very quickly, and is ideal for children as well. The eyepiece is located at the same position on the tube making the observations more comfortable. For imaging purposes it has some limits and can be used to take photos of the Moon or planets only. The telescope used on a Dobsonian mount can be later mounted on an equatorial mount as well. Telescopes up to 50 cm are available.
Telescopes with perfect images. By using the most enhanced glass material all errors of the traditional refracting telescopes can be avoided. The ED lenses provide an optical system which is free from almost all of the optical aberrations. These are best general-use telescopes, providing the best available image quality even in case of fast telescopes. Fast setup means shorter optical tubes as well. Ideal for astrophotography, planetary observations or deepsky watching.
These refracting telescopes represent an intermediate step between the spotting scopes and astronomical telescopes. In practice these telescopes are astronomical scopes optimized for daytime use, thanks to their altazimuth mounts and Amici (erecting) prisms, but still usable for astronomical observations. Recommended as panorama scopes and for ocassional astronomical observations.
These short tubed telescopes are the most compact ones. Because of the shorter tube they're more stable on a given mount and provide very contrasty images even at high magnifications and are excellent to observe Moon, Sun or planetrs. Because of the optical design they're more expensive than similar sized Newtonians. Ideal for anyone looking for a multi-purpose, easy-to-carry compact telescope.
All of the available telescopes (using the proper solar filter) can be used for solar observations but specially designed solar telescopes give a completely different view. These telescopes block all wavelengths except for a very narrow line around the H-alpha line. Solar eruptions and the always changing active surface reveals quite much details.