A spotting scope is easily distinguishable from its distant cousin, the telescope. It's considerably smaller, very portable and uses relatively low magnification - although for scopes with similar uses, it does have a considerably powerful magnification capability. Unlike the telescope, the spotting scope does not produce an upside down image of an object but instead presents an upright one.
Spotting scope is an instrument for viewing the terrestrial objects. It has the functions similar to the telescope but with a portable and easy to carry design. They are better compared to the binoculars and it lies in between the binocular and the telescope. With regard to the cost and the functions, also it is the same standing ahead of the binocular and less than the telescope. They are mostly used for birding and nature observation. It can also be used to view the night sky but is limited to the moon and the stars found in the sky. When more specific details in the sky are required, this instrument does not support and a telescope has to be used.
The technical aspect of the spotting scope is many to discuss. First is the magnification that suggests the uses of the instrument. In the normal case when the field of view is small, the magnification is high. The range of magnification with the spotting scope is 15 - 60x. The lens also is found in many types. The size of the lens diameter depends on the magnification power when the magnification is high the lens size is also bigger. This aperture varies from 50 to 80mm.
The types of optical lens are refractor and catadioptric type. In the refractor type, it uses glass to bring light; it is durable, low in maintenance, simple design, has shorter focal length and is less expensive. In the catadioptric type it uses mirrors, has long focal length, the magnification power is more, it is sensitive and is good for the long distance viewing.
There are also eyepieces that can be attached which increase the performance of the spotting scope. It comes in different power and the user can easily interchange them depending on the situation. There are also zoom eyepieces and they are used to see the detail of the viewing images.
The design of the spotting scope can be handy and many of them have rubber outer covering that makes it waterproof. With the nitrogen gas filling it becomes fog proof. There is a knob for the focus control that can be adjusted easily. It also can be used with the tripod for more convenient viewing. In short, the three types of cope are the straight through scope, angled scope and the shoulder-mounted scope that has different benefits and for the same magnification purpose.
Origin:sanbobo
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