1. An important factor when you start to research telescopes for sale is making sure that you select a telescope that has a large diameter (aperture) lens. The reason why this is important is because the larger the lens diameter the more light it collects and magnifies the object, the better to see the object. If you don’t buy a lens with large diameter, then you run the risk of not being able to see objects as clearly as you want.
2. Select a refractor telescope for seeing details on the brighter planets and the moon. Refractors use a lens to collect the light, which is focused to an eyepiece found at the bottom of the tube.
3. Select a reflector for looking at star fields, nebulae and galaxies. Reflectors use a mirror to collect light, which is reflected and fucused back up the tube to an eyepiece near the front of the telescope.
4. Another type of telescope to consider from all telescopes for sale; is the catadioptic telescope –the Schmidt-Cassegrains and Maksutovs–are hybrids, combining a reflecting mirror with a large corrector lens that eliminates optical distortions. This telescope introduced in the 1970s to amateur astronomers. Its key selling point is its portability. For example am 8 inch (200mm) model has a tube only one-third as long an an 8 inch reflector. It is more expensive. The extensive accessories make Schmidt-Cassegrains a good choice for astrophotography.
5. Remember that the size and weight of any telescope is an important consideration if you’ll have to transport the telescope into a field to get a good place to look without suburban lights blocking out the night sky So if you really want to buy a telescope from all the telescopes for sale, follow these tips to select the scope that will give you the greatest sky viewing pleasure.
Copyright by Timothy Hill 2010