Telescopes are magnifying devices that allow you to observe stars and planets from a distance and can study their surfaces. Telescopes can also be used to measure distant objects on Earth. Overall, they are a popular way to buy for people who want to appreciate the beauty of nature. Learn what to pay attention to when buying binoculars.
What should I pay attention to when buying binoculars?
1. The aperture
The aperture of a telescope is the diameter of the objective of a refractor or a reflector. Aperture size is the real key to a telescope's "power" -- its size is proportional to the telescope's ability to concentrate light. The more light the range can collect, the better the image the observer will see.
However, that doesn't mean you should simply buy the telescope with the largest aperture you can find. If your scope is very large, you are unlikely to use it. Generally, 2.4 inch (60 mm) and 3.1 inch (80 mm) refractors and 4.5 inch (114 mm) and 6 inch (152 mm) reflectors are popular with amateurs.
A good telescope is more than just its power. Three hundred times magnification sounds great, but there's a problem: While high magnification makes objects appear larger, the range collects light that spreads over a larger area, resulting in a darker image in the eyepiece.
Sometimes a lower magnification can provide a better viewing experience, especially if the observer is looking at objects scattered across the sky, such as star clusters or nebulae.
In addition, "high-power" oscilloscopes have specific requirements for eyepieces, so you need to research which eyepieces are best for a given instrument.
3. The eyepiece
Any new telescope should have at least one eyepiece, and some telescopes have two or three. Eyepieces are measured in millimeters, with smaller numbers indicating higher magnification. 25mm eyepieces are common and suitable for most beginners.
As with magnification, a higher power eyepiece does not necessarily mean better viewing power. For example, it allows you to see details of a small star cluster, but if it is used to view a nebula, it will only show part of the object.
It is also important to remember that while higher magnification eyepieces may provide more detail, it is difficult to keep objects in view. For the most stable observations in this situation, you may need to use a motorized stand.
Lower magnification eyepieces make it easier to find objects and keep them in view. It also requires less light, so it's easier to look at darker objects.
The high and low magnification eyepieces each have their place in the observation, so their value depends on the stargazer's interest.
4. The focal length
Focal length is the distance between the main lens/mirror and the point at which the object is focused. Focal length is important because it is one of the factors that magnifies the object in a telescope.
To calculate magnification, divide the focal length of the telescope by the focal length of the eyepiece: If you have a 25mm eyepiece and a 900mm refractor, and the magnification is 36 times, write 36x (or, 900/25 = 36).
To avoid blurring, make sure to magnify the telescope to no more than twice the aperture of the telescope in millimeters (or 50 times the aperture in inches).
Telescopes provide a great way for stargazers to view magnified views of objects in the sky. But whether you're buying your first, second, or fifth telescope, it's important to be fully aware of the above points before heading to the store so you can make the best choice.