Bird watching telescopes can be roughly divided into two types: binoculars and monoculars. Most binoculars are 7 to 10 times magnification, suitable for hand-held viewing of relatively close birds, and are an indispensable weapon for every bird watching enthusiast. Monoculars are usually 20 to 60 times magnification which are suitable for viewing long-distance and relatively slow-moving birds. In addition, monoculars need to be used with a tripod.
Binoculars can be divided into two types: Porro type and roof type . Porro type telescope: simple structure, easy to produce, but large in size and heavy in weight. Roof type telescope: small size, relatively light, but difficult to produce, and the price is higher than that of Porro type.
We often see numbers such as 8*42 or 10*42 in binoculars, where 8 or 10 is the magnification of the telescope, and 42 is the aperture of the objective lens. What is magnification? The magnification is the magnification that brings the object closer. For example: a 700-meter-distance target, if viewed with a 7x magnification telescope, it presents a scene equivalent to 100 meters in front of the naked eye (as shown in the figure below).
Tips: Binoculars usually choose 7-10 times. When the magnification is more than 12 times, the image will be unstable and uncomfortable to observe due to the shaking of the hand, so a tripod is required to support it, which will lose the greatest effect of binoculars: flexibility.
Finally, how to maintain the outdoor bird watching telescope: The ideal way to store the telescope is to store it in a dry and cool place, that is, in an environment with relatively constant temperature and humidity.
1. Dry environment is very important
When water vapor condenses on the glass surface, fog will form on the inside of the eyepiece. Therefore, it is important to place the telescope in a dry place (ideally, the humidity should be low).
2. Temperature fluctuations should be avoided
In addition, it is important that there are no temperature fluctuations (the main cause of fog) in a specific area. Although most high-quality telescopes are anti-fog and waterproof because the inside is filled with anti-fog gas, if the telescope is stored in a place where the temperature fluctuates frequently for a long time, it may still form fog on the glass surface.
3. Close the lens cap
Before storage, you need to cover the lens cover and put it in the box to prevent damage. In addition, the eyepiece may absorb a lot of dust, so it is best to store it with a rain cover or lens cap at room temperature.
4. Desiccant helps a lot
In order to remove excess humid gas, the best desiccant is silica gel, a silica that absorbs up to one-third of the weight of water. Silicone is purchased in a small bag and can be placed in the telescope box.