Magnification 200 times. What can be seen with a telescope? Magnification is the most important characteristic of a telescope

The Nikon Small World microphotography competition is considered the most exciting and respected among microphotographers. Thanks to this genre of photography, we can get acquainted with the beauty, complexity and perfection of nature in objects invisible to our eyes, which can only be seen with a microscope. Among the two thousand most interesting pictures of the invisible world, the jury noted the following winners:

Zooplankton at 100x magnification. To obtain such symmetry, the photographer placed each representative manually.

Photo of a butterfly wing at 10x magnification.

A shot of a ladybug's head, magnified 10 times.

The egg of a heliconid butterfly, belonging to the Nymphalidae family, was approximated 4 times.

Close-up of the venomous fangs of a centipede, at 16x magnification.

This photograph, taken at 50x magnification, captures the formation of air bubbles from molten crystals of ascorbic acid.

This is what an ant pupa looks like at 50x magnification.

If you bring the dragonfly larva 25 times closer with a microscope, you can see such beauty.

On this frame, enlarged 9 times, we can look into the eyes of a jumping spider.

Like a beautiful picture of a talented artist, the substance salicin looks like at a 50x magnification. This glucoside, extracted from the bark of the tree, has a bitter taste and is difficult to dissolve in both cold water and alcohol.

A seed from a headwort plant, approximated five times.

Surprisingly, this is what copper crystals look like at 5x magnification.

Butterfly's coiled proboscis, 6.3x magnification.

The photographer took a leaf of a liverwort plant and magnified it 125 times. That's what came out of it.

At 200x magnification, the insides of ciliated ciliates are visible.

This is a water-dwelling tick magnified 100 times.

Beetle Chrysochroa buqueti rugicollis, 19x magnification.

Approximate 4 times a shaggy caterpillar that clings to a blade of grass with its paws.

The stamen of a black elderberry flower at 10x magnification.

A micrograph of a wasp's eye.

Everyone who chooses their first telescope pays attention to such a characteristic as the magnification of the telescope. How do you know what magnification a telescope gives? What magnification is needed to view the craters on the Moon, the rings of Saturn, the moons of Jupiter? What is the maximum useful magnification? We will try to answer all these important questions in this article.

Is magnification the most important characteristic of a telescope?

Details of the surface of Mars at the same magnification with a telescope of different apertures.

Almost every novice space lover believes that the increase in the telescope is his main characteristic and tries to pick up a telescope with the highest possible magnification. But is the magnification of the telescope really that important? Undoubtedly, the magnification of a telescope is one of the main characteristics of a telescope, but not the only significant one. In order to obtain an image of an object through a telescope not only large, but as detailed as possible, it is necessary that high-quality glass optics be used in the telescope, complex coated lenses in refractors, and parabolic mirrors in reflectors. The quality of the eyepieces you use is also important.

How to calculate the magnification of a telescope?

View of Saturn at 200x and 50x magnification.

The possible magnification of the telescope depends on its initial parameters: aperture diameter, focal length and eyepieces used. The change in magnification is achieved by changing eyepieces and combining them with a Barlow lens. To calculate the magnification of a telescope, you need to use a simple formula: G=F/f, where G- magnification of the telescope, F is the focal length of the telescope, f is the focal length of the eyepiece. The focal length of a telescope is usually listed on its body or in its description, while the focal length of an eyepiece is always written on its body. Let's take an example. The focal length of the Sky-Watcher 707AZ2 telescope is 700 mm, when viewed with an eyepiece with focal length 10 mm gives an increase of 70x (700/10 = 70). If we put an eyepiece with a focal length of 25 mm, then we will get a magnification of 28x (700/25 = 28). When using a Barlow lens, you can achieve large magnifications, because the Barlow lens increases the focal length of the telescope several times, depending on the magnification of the Barlow lens itself. For example, when using a 2x Barlow lens with a Sky-Watcher 707AZ2 telescope and an eyepiece with a focal length of 10 mm, we will get a magnification of 140x instead of 70x.

The maximum useful magnification of the telescope.

The focal length of the eyepiece is indicated on its body.

In optics, there is such a thing as the maximum useful magnification of a telescope. These are the magnifications that the optical system of the telescope can achieve without loss of image quality. Theoretically, when using combinations of short-focus eyepieces and powerful Barlow lenses, even on small telescopes, very large magnifications can be obtained, but such manipulations do not make sense, since the optical system of the telescope is limited by its diameter and the quality of the optics.

View of Saturn at insufficient, optimal and excessive magnification.

At very high magnifications, you will not get a sufficiently bright and clear picture. Therefore, when choosing a telescope, it is important to pay attention to such a characteristic as the maximum useful magnification. The maximum useful magnification is calculated for each telescope individually using a simple formula G max=2*D, where G max is the maximum useful magnification, and D- aperture (diameter of the lens or main mirror). For example, if a telescope has an aperture of 130 mm, then the maximum useful magnification for such a telescope will be 260x.

Moon at 50x magnification.

Be careful when studying the parameters of the telescope in its description. Sometimes manufacturers claim too high figures, for example, magnifications up to 600 times. It should be understood that such values can be achieved with an aperture diameter of at least 300 mm, and then most likely at such an increase you will encounter another problem - strong distortions from the earth's atmosphere.

What can be seen with a telescope at different magnifications?

Lunar relief at a magnification of 350 times.

For observation full moon so that its disk completely fits in the field of view, a magnification of 30-40 times is sufficient. The moon is a very close and large object, in the sky a full lunar disk occupies 0.5 degrees, and if you put an eyepiece giving 100x or more, then you will be able to view the lunar relief in fairly small details - you will see craters of various diameters, mountain ranges and seas.
To see details on the surface planets, you should apply already large magnifications - from 100 times and more, because planetary disks have small angular dimensions. With magnification from 100x it is possible to see disk of Saturn and its rings with the largest satellites, Jupiter's cloud cover and 4 of its largest satellites, see martian surface with dark areas and polar caps.
In order to consider deep space objects, such as star clusters, hydrogen nebulae and galaxies, you will need different magnifications - for extended faint objects, such as nebulae - wide-angle eyepieces with a field of view of 60 degrees and additional filters for greater contrast.
If you chose to observe a bright compact object, such as planetary nebula, for example, the M57 "Ring" nebula, then you will need high magnifications of 200x or more, as well as filters for observing nebulae.
Under observation single stars it makes no sense to put high magnifications in the telescope, because at any magnification, the star in the telescope looks like a shining dot. If the star looks like a pancake or a ring, then the focus is not done correctly or your telescope does not have enough quality optics.
High magnifications must be used if you want to observe binary and multiple star systems, with distinguishable components in a telescope.

Advice:

When choosing a telescope - pay attention to its package. It is necessary that the kit includes various eyepieces that allow you to achieve various magnifications, including the most useful one. Sometimes manufacturers save on accessories, focusing on the quality of the telescope itself. In this case, you need to buy additional eyepieces yourself. This usually happens with high-end models with expensive optics, which require the use of eyepieces of the same high-end.

A telescope is an optical instrument designed to observe celestial objects. One of the main characteristics of a telescope is the diameter of the lens. The larger the diameter of the telescope lens, the brighter the image will be and the higher the magnification can be used for observations.

Let's take two telescopes, in which the lens size differs by 2 times (for example, 100mm and 200mm), and then look at the same celestial object with the same magnification. We will see that the image in a 200mm telescope will be 4 times brighter than in a 100mm telescope, since its mirror is larger in area and collects more light. As an analogy, we can cite two conical funnels with different diameters that stand in the rain, respectively, the one that is larger will collect more water. For comparison, a 70mm telescope lens collects 100 times more light than the human eye, and a 300mm telescope lens collects 1800 times more light.

Also, the resolution of the telescope depends on the diameter of the lens. A high-resolution telescope makes it possible to distinguish fine details, for example, when observing and photographing planets or binary stars.

What celestial objects can be seen with a telescope?

1) Moon. Already in a small 60…70mm telescope one can see a lot of craters and seas on the Moon, as well as mountain ranges.

View of the Moon through a 50x telescope.

Near the full moon around large craters you can see light "rays". The size of the smallest craters available with a 60-70mm telescope is about 8 kilometers, while a 200mm telescope will allow you to see craters about 2 km in size due to its high resolution.

View of the Moon through a 200x telescope.

2) planets. For planetary observations, it is desirable to use telescopes with a sufficiently large lens diameter - from 150mm, since their angular size is quite small, and to a person who looks even through a 150mm telescope for the first time, Jupiter may seem like a small point. However, even in modest instruments with a diameter of up to 114 mm, you can see quite a lot - the phases of Mercury and Venus, the polar cap of Mars during the Great Oppositions, the ring of Saturn and its satellite Titan, the cloud belts of Jupiter and its 4 satellites, as well as the famous Great Red Spot. Uranus and Neptune will look like dots. In larger telescopes (from 150 mm), the number of details visible on the planets will noticeably increase - these are numerous details in the cloud belts of Jupiter, and the Cassini gap in the ring of Saturn, and dust storms on Mars. The appearance of Uranus and Neptune will not change much, but they will no longer be visible just as dots, but as tiny greenish balls. The main thing in planetary observations is patience and choosing the right magnification.

Saturn. Approximate view in telescopes with a diameter of 90mm

3) double stars. In a telescope, they are visible as several nearby stars, either of the same color or different colors (for example, orange and blue, white and red) - a very beautiful sight. Observing closely spaced binary stars is an excellent test of telescope resolution. It should be noted that all stars, except the Sun, are visible through a telescope as points, even the brightest or closest. This is due to the fact that the stars are at a gigantic distance from us, so it was possible to fix the disks of stars only in the largest telescopes on Earth.

Double star Albireo - Beta Cygni. Approximate view in telescopes with a diameter of 130mm

4) Sun. On the star closest to us, even in small telescopes, sunspots can be seen - these are areas with a lower temperature and strong magnetization. In telescopes with a diameter of 80 mm or more, the structure of spots is visible, as well as granulation and flare fields. It should be said right away that observing the Sun through a telescope without special protection (without an aperture solar filter) is FORBIDDEN - you can lose your eyesight once and for all. During observations, it is necessary to fix the filter as securely as possible so that an accidental gust of wind or an awkward movement of the hand cannot disconnect it from the telescope tube. You should also remove the finder or cover it with covers.

Sun when viewed with an aperture filter. Magnification - about 80 times

5) star clusters. These are gravitationally bound groups of stars that have a common origin and move as a whole in the gravitational field of the galaxy. Historically, star clusters are divided into two types - open and globular. The largest open clusters available for observation even with the naked eye - for example, the Pleiades. Without a telescope in the Pleiades, you can see 6-7 stars, while even a small telescope will allow you to see about fifty stars in the Pleiades. The remaining open clusters are visible as groups of stars, from a few tens to hundreds.

Double star cluster h and x Perseus. Approximate view in telescopes with a diameter of 75 ... 90mm

globular clusters in telescopes up to 100 mm in diameter, they are visible as hazy round spots, however, starting from 150 mm in diameter, the brightest globular clusters begin to crumble into stars - first from the edges, and then to the very center. For example, the globular cluster M13 in the constellation Hercules, when viewed through a 200mm telescope, completely crumbles into stars. In a 300mm telescope at the same magnification, it looks even brighter (about 2.3 times) - it's just an unforgettable sight when 300,000 stars sparkle in the eyepiece!

Globular cluster M13 in Hercules. Approximate view through a telescope with a diameter of 250 ... 300mm

6) galaxies. These distant stellar islands are also available for observation in 60…70mm telescopes, but in the form of tiny specks. Galaxies are demanding on the quality of the sky - they are best observed away from the city in a dark sky. Details in the structure of galaxies (spiral arms, dust clouds) become available in telescopes with a diameter of 200 mm or more - the larger the diameter, the better. However, you can study the location of bright galaxies with a small telescope.

Galaxies M81 and M82 in the constellation Ursa Major. Approximate view through a telescope with a diameter of 100-150mm

7) Nebulae are giant accumulations of gas and dust illuminated by nearby stars. The brightest nebulae, such as the Great Orion Nebula (M42) or the nebula complex in the constellation Sagittarius, are already visible with 35mm binoculars. However, only a telescope can convey the beauty of nebulae. The situation is the same as with galaxies - the larger the diameter of the lens, the brighter the nebulae are visible.

The Orion Nebula. Approximate view through telescopes with a diameter of 60-80mm.

It should be noted that both galaxies and nebulae look gray in a telescope, since these are very faint objects and their brightness is not enough for color perception. The only exceptions are the brightest nebulae - for example, in telescopes with a diameter of 200 mm or more near the Great Orion Nebula, hints of color begin to appear in the brightest areas. However, the view of nebulae and galaxies through the eyepiece is a breathtaking sight.

An approximate view of the planetary nebula M27 "Dumbbell" in the constellation Vulpecula in a dark sky through a 250-300mm telescope.

8) Comets– during the year you can see several “tailed travelers”. They look like misty specks in a telescope, and the tail of the brightest comets can be seen. It is especially interesting to observe the comet several nights in a row - you can see how it shifts among the surrounding stars.

An approximate view of a bright comet through a telescope with a diameter of 130-150mm

9) Ground facilities. The telescope can be used as a telescope (for example, to view birds or the surrounding area), but be aware that not all telescopes provide a direct image.

Summarize.

The main parameter of any telescope is the diameter of the lens. However, no matter what telescope you choose, there will always be interesting objects to observe. The main thing is to have a craving for observations and a love for astronomy!

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