How to choose a telescope?

Master teaches you how to choose a telescope!

You can try to find it in commodity distribution centers such as science and technology markets, and you may find it.

Also, you can pay attention to the breeding grounds, optical shops and photographic equipment shops. Sometimes things like this happen. Ordinary shops may not be easy to find.

However, there are many fakes now. Fake and shoddy products account for more than 95% of the market, and there are all kinds of false propaganda, such as "night vision", "infrared", "Japanese cherry blossoms" and "Russia". I suggest you know the basics: ytwscc/...e E.

Pay special attention to issues such as multiple, military and night vision, that is, the introduction of some common false propaganda.

Basically, I have a familiar understanding of these aspects, and the effect of on-site comparison is generally no problem, that is, there are more inferior and counterfeit products, and caution is the most important.

In addition, hand-held generally do not choose zoom. At present, many hand-held telescopes on the market are zoom, and the specifications are similar to 10-30X60 15-40X70. At present, this kind of hand-held telescope can't be said to be 120%, but it can be said that 99.999% are fooled by the parameters of people who are not familiar with telescopes. Don't choose hand-held zoom. (High-powered desktop (tripod) binoculars are relatively high-grade, because the technology is good, you can choose this structure, which is more convenient, but don't choose hand-held binoculars. )

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Outdoor, I personally suggest that the multiple should not be too high. For hand-held telescopes, there is an optimal standard multiple range, that is, 7 ~ 10, and all military hand-held telescopes in service are in this range. Outdoor, I suggest you refer to the military option, which is generally more than 7 times and 8 times, and less than 10 times. You can choose 8 times. This is my opinion. The pandas on the market now are not produced in Guang Yun, but by some small manufacturers. Because Guang Yun has not produced civilian products for many years. Not good, just so-so, low-grade products.

I want to buy binoculars. How should I choose?

In fact, in recent years, many telescope lovers have lost confidence in domestic telescopes, because many informal small manufacturers have produced a large number of counterfeit and shoddy products. In fact, China has made great achievements in telescope optics, but the regular products are difficult to buy in the market because of their small output and high price. Many regular products have been wholesale by shopping malls in major cities, and the price is very high, generally 2-3 times or more of the market price! However, in Jinzhou, Shenyang and other areas of Liaoning, I have also seen some famous brands, such as: Debao (TASCO, BRESSER), Panda, TASCO (USA), BOSMA (Guanbo), NIKULA, and some brands of regular manufacturers in the south. In fact, the performance of these regular products in China is also good, and the overall performance is not inferior to similar products abroad. In Jinzhou area, Debao and TASCO (American/German brand, made in China) series are the most common. However, most of them are in big shopping malls (department stores, Zhong Bai, Hualian Supermarket), and their prices are very high. Of course, telescopes are also sold in shopping malls, electronic markets, single holes and antique markets in CUHK, and the prices of similar products are lower than those of department stores and Hualian. Influenced by the West, China also introduced zoom binoculars. This telescope has a wide zoom range and many uses, and the magnification can be adjusted at will according to different observation targets (including environmental brightness, observation distance and other conditions). However, its optical performance is not as good as that of a single telescope, and its field of view is relatively small, resulting in serious chromatic aberration. At low magnification, good performance. The higher the magnification, the lower the brightness and the worse the definition. At the same time, the deviation of the optical axis will also make the observer feel uncomfortable. Even domestic regular products or imported famous brands have the above problems to some extent. Its price is also relatively high. The market price of an ordinary 50MM diameter binocular zoom model is 300-400 yuan, while the price of domestic regular products and imported famous brands is higher. I don't advocate that you buy a zoom telescope. If you must buy it, buy domestic (imported) brand-name products. Only in this way can the quality be guaranteed. Generally speaking, it is enough to choose 7-20 times (standard multiple) zoom binoculars. As for multiples as high as 30 times or more, it is impossible to talk about it. Even if you have such economic strength, it is also a waste. If a friend is interested in astronomical observation, he might as well buy a domestic boutique telescope and fix it on a tripod for observation. Speaking of some excellent telescopes in China, they are all-metal large-caliber nitrogen-filled waterproof telescopes, medium-caliber nitrogen-filled waterproof telescopes and some new nonmetallic economical telescopes introduced in recent years. These products have excellent performance and are expensive. The specific model and performance are shown in the following table: type, model and price (estimated). Large-caliber boutique double-barrel 20×80 980-3000 yuan all-metal structure, wide-angle and large field of view, BaK4 prism, MC/GMC coating, excellent performance. Nitrogen sealing, waterproof, dustproof and anti-collision. Can be connected to a tripod, suitable for astronomical and ground observation. It is heavy and bulky, so it is not suitable for hand-held observation. Looking at the specific performance, the price gap is also very large. 22× 100 1500-3000 RMB 25× 100 1700-3000 RMB 30× 100 RMB 2000-3000 RMB 65/80/85. Can be connected to a tripod, suitable for astronomical and ground observation. There are straight and folded tubes to choose from. Medium-caliber double-tube 8×40 350 yuan main metal, high-density nitrogen seal, waterproof, dustproof and collision-proof, wide-angle and large field of view, high-quality optical lens, low price and comfortable feel. 10×50 380 yuan 12×50 400 yuan medium caliber boutique double barrel (LOAVA) 8×45 600 yuan all-metal structure, wide angle and large field of view, BaK4 prism, MC/GMC coating, excellent performance. Nitrogen sealing, waterproof, dustproof and collision-proof. 7×50 630 yuan 10×50 660 yuan 12×50 700 yuan economical twin cylinders15× 60/7016× 60/80 20× 60/80 350-700 yuan. ......

Skills of choosing a telescope

If the landlord doesn't understand it at all, it is estimated that he can't choose a telescope that suits him. Then I recommend two websites,

This forum in Mu Fu is an astronomy forum. You can ask about the purchase of a single telescope.

The forum of Beixuanxing is a telescope forum, mainly binoculars. You can ask about the purchase of double cylinders.

What should I pay attention to when choosing a telescope?

Telescopes can usually be divided into the following four types: hand-held binoculars; Single tube bird-watching mirror; Giant binoculars; Single telescope; Don't be superstitious about advertisements or indicators, please compare your choices with your eyes. (2) The optical performance magnification (preferably between 8 times and 10 times) is marked with the words 10×42, 8×30, etc. The former represents the magnification and the latter represents the objective lens diameter. Look at a bird standing at 100 meters with a telescope that is 0/0 times that of100 meters, just like looking at it with the naked eye. Because the magnification is too large and the viewing angle is smaller, it is more difficult to search for the target, and it is easier to affect the clarity because of the trembling of the hand. When the light is very sufficient, 10 times is clearer than 8 times; When the light is insufficient, 8 times can see the details better than 10 times, and you can't blindly pursue high magnification. The larger the aperture (it should be between 30mm and 42mm), the better. The diameter of the objective lens affects the amount of light entering. Especially in the case of strong contrast between light and dark, dusk and cloudy, the larger the aperture, the higher the amount of light, and the more details the eyes can see; But at the same time, the heavier the telescope, the easier it is to cause fatigue when watching it for a long time. You should choose a larger caliber according to your physique. The visual field (the bigger the better) refers to the range that can be seen from 1000 meters, and the width of the visual field is higher than 104 meters or 6 degrees. The larger the field of vision, the faster and easier it is to search for the target. However, the larger the field of view, the more serious the distortion and blur of the edge, the more complicated and difficult the aberration correction, and the higher the technology and cost required. Color fidelity (the more natural, the better) A high-quality telescope must faithfully reflect the primary colors and color saturation of the scene. In order to increase the brightness of the telescope, some manufacturers deliberately increase or decrease a certain light wave, which leads to distortion and makes the scenery appear blue or red. The relationship between light transmittance and coating is inseparable, which directly affects color fidelity. All optical glasses are coated with multi-layers with high transmittance, high brightness and accurate color reproduction. General manufacturers will not publish all the data (it is difficult to do), and some manufacturers will publish the transmittance or coating of local optical glass to mislead consumers. The best way is to observe and compare with your own eyes. (3) Performance 1) Depth of field is a contradictory parameter for birdwatchers. If the depth of field is large, it is convenient to use without frequent focusing, but for bird watchers, the foreground and background are not easy to blur and birds are not easy to stand out. However, the depth of field is small. Although the foreground and background are blurred obviously and the theme of the bird is prominent, it is very tiring to refocus when the distance changes, and I always put my finger on the focusing wheel. This depends on personal preference, there is no fixed standard. 2) Sealed telescopes are often carried out outdoors, and the observation environment is changeable. It is best to choose a telescope that can be waterproof (water pressure and waterproof), so as to keep the seal inside the mirror stable, free from fog and mildew. 3) Comfort Comfort varies from person to person. Generally speaking, for the telescope with rubber coating on the surface, it is not only effective in shock prevention, but also more comfortable to hold; The weight of the mirror determines whether it is convenient to use and carry for a long time; Usually, people will choose a telescope with high durability. 4) The brand chooses the best telescope, besides the optical quality, manufacturing technology and performance, it is more about the feelings of eyes and hearts. Zeiss in Germany, Leica and Swarovski in Austria are also called the kings of mirrors. The optical quality and price of the three are almost the same, and the price is the king in the mirror, but it is still worth the money based on excellent top products. In addition, Germany's cross-fitting is also very good, but there are few all-metal mirrors in the domestic market, and the price is too high. The original brands such as Nikon, Canon, Fuji, Minolta, Pentax and Olympus are all good, but telescopes made outside China are not. The products in China market are mostly EOM products from Zhejiang, Yunnan and Guangdong, and the product quality is average. Domestic military materials and high-grade export foreign trade products have the best cost performance. Domestic Type 95, Type 62 and Ares are all good products. The all-metal mirror body of Russian telescope is classical in shape and deeply loved by military fans and optical enthusiasts. However, due to the lack of formal purchase channels and normal after-sales service, defective products and defective products have also flooded into the market. When choosing binoculars, you should do according to your own needs. At the same time, don't be superstitious about advertisements or some local indicators, but compare them with your eyes and mind.

How to choose a monocular telescope?

About magnification: each telescope is marked with main parameters, such as 7 * 35, which means 7 times the mirror surface and 35mm objective lens. Generally, below 6 times is low power, 6- 10 times is medium power, and above 10 times is high power. Many people always think that the higher the multiple, the better. Some manufacturers also use false high magnification to attract consumers. In fact, the reasonable magnification of the telescope is related to the aperture and observation mode of the telescope: the larger the aperture, the higher the magnification, and the fixed observation with tripod can be higher than the handheld observation. If you buy hand-held binoculars, 7- 10 times is enough, and at most it is not more than 12 times. Otherwise, the higher the magnification, the smaller and darker the observation field of view will be, and the observation effect will be reduced, especially the jitter caused by high magnification will be greatly increased, making the observed scenery unstable and difficult to observe normally. Although there are many kinds of telescopes in the world, including American and Russian, most of them are 6- 10 times. Some world-famous brands such as Zeiss and Nikon also produce telescopes with medium magnification, because clear and stable imaging is the most important.

About aperture: The larger the aperture, the greater the observation field of vision and brightness, which is conducive to observation in dim light. But the larger the aperture, the greater the volume and weight, and the higher the cost. Generally, it can be selected between 30 and 30-50 mm as required.

About the field of view: the field of view refers to the field of view that can be observed at a kilometer, such as 1000/93m, which means that the telescope can observe a range of 93m wide at a kilometer, or it can be converted into "degrees" and expressed as 5 30'. The comparison of the size of the field of view must be carried out under the condition of similar caliber and the same multiple. The key to the size of the field of view lies in the design of the eyepiece part of the prism system. General famous factories and advanced varieties of military telescopes all adopt wide-angle and large-field design, which will give people a feeling of being broad, comfortable and relaxed.

About coating: the function of lens coating is to reduce reflection, increase light transmittance and improve observation brightness. Different coating colors have nothing to do with quality. The thinner the coating, the smaller the reflection, the better. However, in recent years, various red and yellow film telescopes with strong reflectivity have appeared in various markets, which are very attractive to consumers. In fact, this inferior coating reflection has lost a lot of light, making the color colder and darker, and the clarity is reduced. What's more, some people even call this inferior red film telescope "night vision" and "infrared night vision telescope" to deceive consumers, which is actually true.

Structural materials: In order to reduce the cost, most ordinary telescopes on the market use plastic lens barrels, and only a few advanced products and military models use all-metal structures, which are expensive, but their durability is unparalleled. Although the appearance of several Soviet-made all-metal military telescopes collected by the author decades ago is very old, the operation of each part is still flexible and the optical performance is excellent.

How to choose a telescope? What kind of telescope is better for 50 minutes?

Hello! First of all, according to the price, choose the mirror with the best performance in this price, and the telescope that suits you is a good telescope.

How to choose binoculars?

When we get the telescope, we will notice its specifications, A×B, where A is the magnification and B is the aperture size of the telescope, in millimeters. These two indicators determine the specifications of the telescope and are also the most important parameters.

Because the telescope is an instrument for observing distance, its function is to enlarge the target and make it easy to observe without losing the original details of the object as much as possible. That is, the ideal telescope should "enlarge the target without loss and truly restore the details."

1. Misunderstanding of telescope multiples

Many people think that the larger the magnification of a telescope, the better. In fact, the magnification of a telescope is determined by many factors. Practice has proved that the magnification of the telescope most suitable for hand-held observation should be 6- 10, at most 7 or 8 times. Generally, the magnification of telescopes on the market will not exceed 20 times. If it is marked hundreds or thousands of times, it is undoubtedly a fake.

Why not increase the multiple? In fact, there is no technical difficulty in high-powered telescopes. Any high magnification will do as long as you like. However, high magnification will bring many negative effects.

The first is brightness. The higher the multiple, the worse the surface brightness of the object will be, because the area of the object is enlarged to be proportional to the secondary amplification, and the brightness will drop very obviously. Of course, if the telescope has a large aperture, the magnification can be appropriately higher, but the aperture of a hand-held telescope generally does not exceed 50 mm, and what is more important is the jitter caused by high magnification. There will be slight jitter in the hand-held telescope, but this slight jitter will become very obvious after amplification. When the magnification is greater than 10, the jitter of the image has made it impossible for human eyes to fully observe the details of the image and give full play to the resolution of the telescope. What's the use of increasing the magnification of the telescope at this time? If the telescope can be fixed on a tripod for observation, the magnification can of course be higher, but for the ground observation telescope, due to the limitation of brightness and resolution mentioned above, the magnification will not be too high, otherwise the image will be very dim and fuzzy, and the field of view will be too small, making it difficult to find the target. The magnification of the large-scale binoculars with the highest magnification I have ever seen for earth observation is 60 times, and the aperture exceeds100 mm. In recent years, there have been image-stabilizing telescopes abroad, and the famous products are Canon Canon and fujinon. They use electromagnetic stabilization technology to "stabilize" images, so that hand-held telescopes can also observe at high magnification. Even the US Army has adopted the image stabilization telescope product of Fuji Dragon, and the standard number is M25 military telescope. Of course, this kind of telescope is expensive, bulky and heavy, so it is not widely used.

Therefore, it is recommended to choose a hand-held telescope, 7- 10 times. Do not select more than 10 times.

Two. Telescope aperture

The aperture of a telescope is one of the most important parameters of the telescope. The larger the aperture of the telescope, the higher the theoretical resolution will be (but it should be noted that in fact, the theoretical resolution is far from being used, which is generally beyond the reach of hand-held telescopes, so the actual resolution is more important, which depends on the optical quality of the telescope). The higher the concentrating power (the higher the brightness under the same multiple), but at the same time, the larger the size and weight of the telescope, and the higher the price. Hand-held telescopes are generally 20-50 mm, but it should be noted that the actual aperture of some low-quality telescopes is smaller than the nominal value because of the prism shielding and the small internal aperture. At the same time, the brightness of the telescope is also closely related to the quality and performance of the coating. A small and high-quality telescope can often observe more effectively than a big and poor telescope.

3. The diameter of the telescope.

The value of the telescope aperture divided by multiple is called the exit pupil diameter of the telescope, that is, the diameter of the beam emitted by the telescope from the eyepiece. This value is not usually marked on the telescope, but it can be easily calculated. It can also be measured directly. The eyepiece of the telescope is facing itself, the objective lens is facing the bright place, and the eyepiece is at a certain distance from itself. At this time, you can see a bright circular spot whose diameter is the exit pupil diameter of the telescope. If it is not very round and not trimmed, it means that the prism is not good enough or not big enough. If we know the multiple aperture and exit pupil diameter of the telescope, we can calculate the third one, so we can use this to verify the accuracy of the telescope's nominal. Formal product names are mostly accurate. The diameter of the telescope's exit pupil directly determines the surface brightness of the object seen by the telescope. The larger the exit pupil diameter, the higher the brightness, and the brightness is proportional to the square of the exit pupil diameter. However, when the diameter of the exit pupil is larger than that of the human eye pupil, some light will not enter the human eye and be disturbed. ......

How to choose a telescope

Seeing that the parameters listed in your list should be binoculars, simply explain the meaning of these parameters: 1. Objective lens: 25mm, which is the aperture of the objective lens. You can directly understand the diameter of the objective lens (that is, the large lens at the far end of the telescope), which is the most important parameter of the telescope. 25mm telescope is portable, which has the advantage of being small and easy to carry, but the effect is average. If you want better effect, you should choose 50 mm. Eyepiece: 12mm, this should be the eyepiece aperture, which is of little significance; 3. Exit pupil distance: 6mm. Simply put, the pupillary distance is the distance between your eyes and the eyepiece when you are observing. The exit pupil distance is between 10 mm and15 mm. If it is less than 8 mm, anyone will feel uncomfortable. Obviously, your 6mm is too small, so you need to keep your eyes close to the telescope when observing, which will be very uncomfortable. 4. The exit pupil diameter: 2.7 mm, the larger the exit pupil diameter, the greater the imaging brightness. The pupil diameter of our eyes varies from 2mm to 7mm, depending on the darkness of light. Therefore, it is significant that the diameter of the exit pupil is within 2mm to 7mm. Your exit pupil is 2.7mm in diameter, which should be dark and suitable for daytime use. The exit pupil diameter is calculated by dividing the objective aperture by the magnification. 5. Coating is to reduce the chromatic aberration of the telescope. Nowadays, telescopes are generally coated. 6. Visual object: 96m/ 1000m, which should be the visual field, that is, the size of the visual field. The range you listed represents 1000m, and the visible range is 96m. 7.Zoom, as you said, can zoom in and out. However, it is not recommended to buy a zoom telescope, because the advantage of zooming is practical and convenient, but at the cost of reducing the optical effect, the zoom system is easy to be out of step and damaged, and the high-power field of view is small. Moreover, due to the addition of a zoom lens, optics is not easy to process. Therefore, some zoom lenses are prone to optical axis problems or zoom synchronization problems after long-term use. Its optical performance is also worse than that of similar fixed-focus lenses. First of all, if you have questions, let's continue to communicate.

How to choose a telescope? What's the difference between a big one and a small one?

Telescope, larger observation comfort is better, although clumsy, but the effect is often better than the small one, and the cost performance is higher.

The small advantage lies in portability, but at the cost of low effect and cost performance.

In fact, many of these questions you ask belong to basic common sense: Gong twscc/...e E E.

For example, the hand-held multiple is 7 ~ 10, and 8 is generally recommended instead of 10. Of course, I'm talking about holding a telescope.

There are many kinds of telescopes, such as hand-held and desktop.

In addition, for hand-held binoculars, a single tube has no stereoscopic effect, so it is generally better to choose binoculars.