A good telescope is an indispensable tool for astronomers. However, there is a wide variety of telescopes on the market with huge price differences. Expensive telescopes may not necessarily have good performance, but it is not necessarily true that cheap telescopes have poor performance. If you do not know how to buy, it is easy to jump into the "expensive is good" pit, so how to buy a telescope that suits you? Here are a few aspects worth paying attention to:

Firstly, it is important to understand your needs. Different types of telescopes are suitable for different areas and details of observation. Common telescopes are refracting telescopes and reflecting telescopes. The former is more expensive, has a higher refractive index, and the downside is that it can be slightly bulky compared to a reflector telescope of the same aperture. The latter is relatively cheaper, has a larger aperture, and the convergence position is not as complicated as that of a refracting telescope, so it is better than a refracting telescope for deep-sky object observation. In addition, the need for portability is also a factor to be considered. If one is only observing at home, then a reflecting telescope with a large aperture and high weight may be more suitable. If you need to go out frequently, then you can choose a telescope with a moderate aperture that is easy to carry. In addition, in terms of aperture, generally over 48cm is a large aperture telescope, 35-48cm is a medium aperture telescope, 20-35cm is a small aperture telescope, and under 20cm is a miniature telescope. Considering the observing place, observing object, observing frequency, observing purpose and other factors, you can buy a suitable aperture and type of telescope according to your own needs.

Secondly, we should pay attention to buying regular brands. There are many kinds of telescopes on the market, and the brands are also various, which requires us to do a good job of research before purchase. Telescope is a precision optical instrument, the quality gap between different brands may be very large, the high price of "cottage" product quality often can not be guaranteed. The regular brand of telescope repair, maintenance and after-sales service will be more guaranteed. Some professional telescope brands will be based on different types and uses to launch different products, consumers can choose the relevant brands and models according to their own needs.

Also, focus on the parameters of the telescope. The performance of a telescope needs to focus on its parameters, such as aperture, focal length, magnification and resolution. Aperture is the most basic parameter of a telescope, which can determine the telescope's "visual acuity", usually the larger the aperture, the wider the observation range and the higher the resolution. However, telescopes with the same aperture often have different focal lengths, and the length of the focal length affects the size of the observed objects and the field of view, so it is necessary to choose a different fit according to the observation target. Magnification refers to the telescope through the eyepiece and objective lens with the magnification of the field of view of the times, the higher the magnification of the object is bigger, but the distortion is also bigger, used to observe a wide range of other more practical than used to observe the local. Resolution, on the other hand, can determine the degree of clarity and resolution of the telescope, including optical resolution and visual resolution. Whether you gather information from literature, trial articles, forums or the official websites of telescope manufacturers, it is important to focus on these parameters and pick the right telescope for your needs.

Finally, consider whether you need additional accessories. While the telescope is the main body of observation, accessories are equally important. Good accessories can further improve the performance of the telescope and can increase the flexibility of observing. Often, it will come with tripods, mounts, etc., and even auxiliary optics such as red dot pointers, star chart chronographs, torches with red light filters, condensing screens, and so on. Although some of these things are not essential, they are very useful for some enthusiasts. Also, when shopping for accessories, special attention should be paid to their quality and the models that fit the telescope.

In short, when you spend your efforts and money to choose your own telescope, don't be confused by the price and ignore some important performance indicators. Comprehensive understanding of their own needs, buy a regular brand of binoculars, understand the parameters, and then consider whether you need additional accessories, so that you can not afford to choose a suitable telescope.