John Tiffany
- 29 Jun 2022 06:28
- 798
1. What is a telescope?
The telescope or telescope was invented in 1608 by Hans Lippershey. What are telescopes used for? People use it to observe celestial objects in the sky or objects that are very far away from humans. They are used in many fields such as military, maritime, aviation ...
Nowadays, in daily life, many families also buy more telescopes to serve their spiritual life.
2. Types of telescopes
There are many types today, and they have different advantages and disadvantages, including refracting, reflecting, and combinatorial telescopes.
- Refractive telescopes
Glass uses 2 convex lenses to focus light. This is a common type of glass.
The advantage of glasses is that they are easy to use, help you see objects in the sky and from a distance, and do not require much maintenance.
However, the disadvantage of glasses is that the image color is not true due to poor light, resulting in not being the best viewing glasses.
- Reflecting telescope
A type without a lens, but with two concave mirrors that bend light.
The advantage of this type is that the images of faint and distant objects are very clear thanks to good magnification and beautiful and realistic image colors.
The downside is less durability, the need for regular maintenance, and the opening of the dust collector.
- Combination telescope
It is a combination of a lens and a mirror. Light enters the glass through a refracting lens. The bounced image hits the side of the lens and then passes through the eyepiece.
The advantage is very good viewing of faint objects, excellent astrophotography, and observation.
The downside is that the price is quite high, and the glass is bulky.
3. Experience choosing a telescope
- Choose a refracting or reflecting telescope?
The two types of glass that are widely used today are refractive and reflective glass. So which one should you buy? Each type has its advantages and disadvan
| Refractor Telescope | Reflecting telescope | |
| Advantages | - Clear image quality. - Durable, low-maintenance products. - Simple, easy to use. | - Give images with true color. - High magnification. - Good price. |
| Defect | – Color is not good due to low light gathering. - High price. | - Large mirror diameter, difficult to carry. - Need regular maintenance |
- Choose Aperture
Aperture represents the diameter of the lens or mirror that captures light, which in turn helps you determine how far you can see. The larger the aperture, the more light the glass receives, and helps you see distant objects more clearly.
For example, if you look at a star through a small, cheap lens, it will only look small, and not clear. In contrast, through a large telescope and good quality, the image is larger, brighter, and magnified more clearly.
Glass with a high aperture will cost more and will be bulkier. Minimum aperture of 80-90mm to help you see details. You should consider your financial situation and needs. If you want to make it easy to move your glasses, you can choose glasses with a small aperture.
- Choose a focal length
Focal length is calculated as the distance between the focal point of the lens and the focal point. The focal length of the lens is expressed in numbers. If the number is small, the viewing angle is wider, the object is far and small. If the number is large, the viewing angle is narrow, the object is closer and bigger, clearer. Thus, the larger the focal length, the better while observing.
- Magnification
Magnification shows the ability of glasses to see distant objects. If the magnification is large, the image will be sharper and clearer.
- Choose a good stand
The stand is used to raise the glass, so it is a very important factor when buying. If the base is not of high quality, the lens easily shakes in strong windy conditions, you cannot get a perfect experience when using it. Besides, it is easy to damage your glasses.
The glasses with EQ or AZ feet are quite sturdy and suitable for you to observe. Now, there are also glasses with a self-targeting stand, which saves you time and effort when adjusting the glasses, as it will automatically shift the lens to the object you want to observe, and automatically move the lens. move with that object. Of course, the price of this type of glass with a stand is quite high.
- Don't buy cheap glasses
You should not buy a pair of glasses that are too cheap, because the quality may not be good, and long-term observation may hurt your eyes. An overpriced pair of glasses should not be the first choice either, because if not used much, or for research purposes, this is a waste.
3. Some notes when using Telescope
You also need to pay attention to a few things when buying and using glasses to satisfy the most needs.
- Don't look directly at the sun
You should avoid pointing the lens directly at the sun, as this will harm your eyes. You should also avoid looking directly at other bright objects when observing.
- Place the glass on a firm surface
If you do not place your glasses on a stable surface, there is a chance that the glasses will be easily damaged, and it will be difficult to adjust the coordinates of the glasses. Remember to always put the glasses on the tripod at an ideal point, not rough to make the observation more convenient, and to avoid costly damage.
- Too much magnification will make the image blurry
Adjusting the magnification makes the image magnified and easier to see. However, the image quality will be less clear and realistic. Please choose the most suitable magnification.
- Take good care of your glasses
Note that you should not leave your glasses in humid or high humidity places to avoid damage.
When cleaning, avoid using products with strong detergents, use soft cloths and periodically wipe them.
By, John Tiffany