How to choose a telescope?
Today there is a fairly wide range of telescopes. These are telescopes for beginners, in which there is a homing function and telescopes for professionals. The demand for them is large enough, since such an increase not only allows you to expand the knowledge of nature, but also gives you the opportunity to know yourself better. However, before choosing a telescope, you need to decide what you need.
Telescope: which one is better
Before choosing a telescope, it is necessary to determine the manufacturer’s company, the type of telescope’s optical system and its mount (this will be what the telescope will be mounted on). The most common today are optical systems of telescopes, such as refractors (lens lens) and reflectors (lens mirror), Cassegrain, Maksutov-Cassegrain and Schmidt-Cassegrain systems, with a combined set of mirrors and lenses. Of course, you can choose a telescope based solely on the appearance parameters, however, you should not forget that the choice of the optical system is one of the most important parameters. Consider the basic parameters of optical systems.
In telescopes, refractors use a lens as an objective in the front of the tube. They are distinguished from other systems by a large length. It is worth noting that with the increase in the diameter of the lens, the price also increases significantly. It depends on the fact that the manufacture of a large, high-quality lens is a rather complicated process, in contrast, for example, to the manufacture of mirrors for Newton systems. There are also telescopes, which are used mainly for astrophotography. They use the “apochromat” refractor system, which has a shorter pipe length (i.e., a focal point), however, they are more expensive. Telescopes with a refractor system are best used for observation in open areas, as they are inconvenient for observation from an open window or balcony. Such a system is great for children, since special difficulties when working with it should not arise. And unlike mirror telescopes, telescopes refractors are not whimsical to different temperature regimes.
Optical systems of reflectors, such as, for example, the Newton system, are fundamentally different from the system of refractors.A concave mirror is used here as a lens in the back of the tube. It is much easier to make mirrors than lenses, so a telescope reflector with a tube diameter similar to that of a refractor tube will be much cheaper. Most often, the reflectors are installed on the equatorial mount. It can be difficult to use for children. However, with long observations more functional and convenient than the azimuth. Similar telescopes can be installed on the Dobson mount, which is cheaper, but not suitable for navigation and accurate observations. Since the reflective layer of mirrors is very thin, they require a more careful attitude. Regular, abrupt changes in ambient temperature are very dangerous. Therefore, in order to avoid covering mirrors and other parts of the pipe with condensate, it is recommended to cover the telescope after observation. To date, you can choose reflectors from 80-100mm. in the diameter of the lens, up to 150mm. and even up to 250. If your goal is to save as much money as possible, but the luminosity of the telescope is not the last for you, and you want to observe far and weak objects - this type of telescope will certainly suit you. This does not mean that such a system is worse than the rest.Any optical system has its differences, certain advantages and, of course, disadvantages.
Which telescope is better to buy
When choosing a telescope, be sure to consider the purpose for which you acquire it. Consider the possible options:
- If you acquire your first telescope, then such a telescope as a refractor 70-90mm., Newton's reflector 110-130mm is perfect for this role. or "Maksutov-Cassegren" 90-100mm.
- When choosing a telescope for a child, it should be borne in mind that, as usual, children are less demanding on the device, unlike adults. Your first exciting walk through the starry sky will help your child to make inexpensive refractors and reflectors 70-80mm.
- If you need a telescope for planetary observations and serious research of various planets, it is better to use refractors 120-150mm. Such tools give contrasting, bright images, as they lack central shielding.
- Choosing a telescope for observing objects of far space, such as faint galaxies, nebulae and clusters, 200-250 mm reflectors will be more suitable. on the Dobson mount or equatorial mount.
- If you still can not decide for what purposes you need a telescope, you can purchase a universal telescope. The optimal choice is a refractor 100-120mm., A reflector 130-150mm. or 127mm. Maksutov-Cassegren.
- If you need a telescope that can be safely transported, pay your attention to telescopes created using the Maksutov-Kassegren system. They are light enough and compact and are perfect for transportation. In addition, you can also use a high-quality telescope, a short-focus refractor.
- If you want to do astrophotography, you just need to use a stable equatorial mount, which is best suited for shooting various objects with a long exposure. It has a smooth ride and is equipped with electric drives on both axes.
- If you need a telescope to observe ground objects, purchase the Maksutov-Cassegrain telescopes or short-focus refractors best. They are installed on azimuth mount and equipped with a wrapping prism, which gives a direct image.
How to choose a telescope we figured out.But the last thing to do is to make sure that the telescope has all the necessary accessories: a set of eyepieces, a finder, a zenith prism, a set of light filters, etc. The low price of some models is often due to their incomplete set. Undoubtedly, all the necessary fixtures can be purchased later. However, consider whether it is necessary, if you pay a little money, you can get everything at once.
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