A telescope is a device that has the ability to make faraway objects appear closer, this is made possible by increasing the size of the object and gathering as much light as possible around the object to make it visible. It was first designed by GALILEO a mathematics professor, the name is derived from a Greek word that means far seen. It was first built in Holland before it spread in Europe.
It is comprised of two lenses the objective lens which is a convex lens and an eyepiece lens, which when held at the right distance produces a surprising optical effect, they act as magnifying glasses for distance objects.
Before you select the right telescope, you need to consider a few important factors. Make sure you check the following things:
1. Physical Size (Portability)
This comes in handy when the type of work required is on the inside in the comfort of your house or workplace or it requires you to carry it up and down when using. Some of the questions you need to ask yourself are will you be carrying the telescope or it is stationed at a specific place this will lead you to whether to buy a big or a smaller telescope for easy movement. The disadvantage of moving with a telescope is that are you able to set the telescope alone.
2. Eyepiece
Most telescopes come with poor eyepieces even the most expensive telescope so it is advised after buying a telescope it is advisable to check the eyepiece since a poor eyepiece may ruin the telescope. Eyepieces are important since they are used in magnification of the object it also helps in angle viewing. So, a better eyepiece is necessary for a telescope. The low-grade eyepiece can be known because it is marked SR of H so avoid such eyepiece.
3. Aperture Size
This is the diameter of the objective lens or mirror usually measured in millimeters, normally the larger the aperture the brighter the image appearance it also leads to the deeper into the space you will see. Its ability to gather more light depends on the aperture size which is directly proportional to the clarity of the image that will be displayed on the eyepiece lens. So, depending on the magnification you want you can choose between a smaller aperture and a bigger aperture.
4. Focal Ratio
This comes about by dividing the focal length by the aperture, you have to make sure you are using a telescope with an accurate focal ratio for a good view of the object. This really helps a lot of researchers to get the actual calculation so it is a matter to be considered before buying a high-performance telescope.
5. Focal Length
This is achieved when dividing the aperture size into focal lengths. It is measured from the mirror or main lens to where the light converges to focus. A higher focal ratio does not necessarily mean a clear view since there are two main factors that determine a decent view: the atmospheric conditions and aperture diameter. A telescope with a longer focal length produces a narrow field of view the only advantage is that it has a good magnification, but a telescope with a short focal length gives a wider field of view the disadvantage is that it provides less magnification
6. Magnification
This is the ratio at which an object is brought closer to the eye and with what clarity. For beginners it may not be that important this is normally for professionals how much a telescope magnifies matters a lot, this magnification really depends on the eyepiece lens used because only more detail exists in the image created by the main lens.
7. Good Telescope Mount
A mount is equally important as the tube and optic in a telescope. The mount is a stand that holds the telescope firm, there are two types of mounts, equatorial and altazimuth. Altazimuth normally allows the telescope to move up and down, forward and backward directions while that of an equatorial is made in a special way in that it follows the movement of an object in the sky. So, before getting a telescope a will advise you to see the type of mount used in order to satisfy your needs, but for space viewing equatorial mount is the best since some come with microcomputers and a motor to keep the object in the field of view longer and automatic aiming of the scope.
8. Cost
The price of a telescope will depend on the type of telescope you want to purchase it could be for hobbies or for research or for learning purposes if you just want to see the moon and planets you don’t need to spend a lot of money. The price range is from $99 for a small refractor telescope to over $20000 for a big catadioptric.
There are three types of telescopes;
- Refractors telescope – this is a telescope whose focusing abilities rely on the lens an example of a refractor is the small telescope used a small telescope in department stores and is also used in rifle scopes.
- Reflectors telescope – this is a telescope whose focusing abilities rely on a mirror as its objective
- Compound telescope (catadioptric) – this type of telescope uses both lens and mirror for focusing.
Final Words
When using a telescope, you may notice not all days the sky has a clear view it differs depending on the earth’s turbulence or sometimes the condition such as warm air rising this observation allows objects to appear faint. After considering the above factors it may help you in choosing the best telescope that suits you. You can pick the right telescope with the features you want and I hope this guide has provided you with important information.
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