There are actually some technicalities that go into buying your first telescope. Many times what people think they want and what they really want are two very different things. Just like with any other large purchase, you have to ask yourself two simple questions:
1. What do you really want to do with your telescope?
2. How much money do you want to spend?
It’s often a good idea to start out small and work your way up to “bigger and better”. If you don’t have much money to invest, you may want to start out with a pair of binoculars. Even the cheap ones will amaze you with how much you can see of the night sky. Binoculars are classified according to their optics (7 x 10 for example). The first number is the magnification factor and the second number is the size in millimeters of the objective lens.
Obviously, the larger the first figure is, the larger the magnification is, but you will have a smaller field of view. The larger the second figure, the more light is gathered by the binoculars and therefore fainter objects become visible.
Seven to ten times magnification is the optimum you should look for in a pair of binoculars for general use. The objective lenses should be between 40mm and 50mm. If there is anything less then the light grasp may be insufficient, anything greater and (apart from the additional expense) the binoculars will start to become too heavy to easily hold by hand.
Many binoculars suitable for astronomical use start in the 7 x 40 to 10 x 50 bracket. If you do decide to buy something larger, say 10 x 70, you will almost certainly have to consider mounting them on a tripod - they will be difficult to hold by hand. Up to 20 times magnification may be considered in a set of binoculars but again, a tripod will become a necessity. In any event do find out if the binoculars have the facility to be tripod mounted - not all of them can!
Binoculars will bring into view the brighter star clusters, galaxies and nebulae. They can be used to help locate an object with a telescope, identifying the chosen target before bringing the telescope to bear on it. Bright variable stars, comets, satellites and large scale night sky features are all well suited to observation with binoculars. The bright planets can also be spotted in twilight with binoculars so overall they are a useful instrument for both the beginner and the experienced astronomer.
A good pair of binoculars will run you anywhere from $50 to $250. Of course, this will depend on where you buy them and your area, but this is a good general number to expect to pay.
Labels: Telescopes
