A factory-made telescope is quite expensive, so it is advisable to buy it if you are seriously interested in astronomy. And amateurs can try to assemble a telescope with their own hands.
As you know, there are two types of telescopes:
- Reflex. In these devices, the role of light-collecting elements is performed by mirrors.
- Refractory– equipped with an optical lens system.
DIY refracting telescope
The design of a refracting telescope is quite simple. At one end of the device there is a lens - a lens that collects and focuses light rays. At the other end there is an eyepiece - a lens that allows you to view the image that comes from the lens. The lens is placed in a main tube called the tube, and the eyepiece is placed in a smaller tube called the eyepiece assembly.
An ordinary telescope made from a magnifying glass
- Making the main pipe. Take a sheet of thick paper and roll it into a tube using a flat stick or a suitable pipe with a diameter of 5 cm. The paper inside should be painted black and not shiny. We make the pipe 1.9 meters long.
- Making an eyepiece tube. It should be put on the end of the main one. We roll it up from a sheet of paper 25 cm long and glue it. The inner diameter of the eyepiece tube must match the outer diameter of the main tube so that it moves effortlessly along it.
- Working with lenses. We make two lids from thick paper. We will place the first one where the lens will be, and we will attach the second one to the end of the eyepiece tube. In the middle of each cap we will make a hole with a diameter slightly smaller than the diameter of the lenses. We install the lenses with their convex side outward.
To do interesting photos starry sky, you can attach a webcam to a telescope.
Telescope from binoculars
From ordinary eight-power binoculars you can build a telescope that provides magnification of over 100 times. Pipes can be glued together from whatman paper. Lenses are suitable from old filmoscopes or similar in magnification. We use calculation simple telescope, and we select the length of the device and the distance between the eyepiece lenses experimentally.
There is no need to disassemble the binoculars - the tubes are put directly on it. For ease of use, you can make a tripod. Such a telescope from binoculars allows you to see mountains and craters on the surface of the Moon, satellites of Jupiter, etc.
conclusions
Making a homemade telescope at home is not particularly difficult. Even a high school student can do this kind of work. For a child, a device with a magnification of 30–100 times will be sufficient.
However, there are home craftsmen who can independently assemble a three-hundred-power high-quality telescope. Such skills come with experience and can be useful to those who are seriously interested in astronomy.
Telescope- the dream of many, because there are so many stars in the universe that you want to look at each one. Store prices for this device are a bit steep for ordinary people, so there is an option to make a telescope with your own hands.
How to make a telescope at home?
For the simplest telescope we need:
Lenses, 2 pcs.;
- thick paper, several sheets;
- glue;
- magnifying glass.
Telescope diagram.
There are two types of telescopes - refractors and reflectors. We will make a refracting telescope, since lenses for it can be bought at any pharmacy. A spectacle lens is required, diameter - 5 cm, diopters +0.5-1. For the eyepiece we will take a magnifying glass with a focal length of 2 cm.
Let's get started!
How to make the main tube for a telescope with your own hands?
From a sheet of thick paper, make a pipe, approximately 5 cm in diameter. Then, straighten the sheet and paint over it inner side in black. You can use gouache paints. Rewind into a tube and secure the position using glue.
The length of our pipe should be about 2 meters.
How to make an eyepiece tube for a telescope?
We make this pipe in the same way as the main one. Length - 20 cm. Don't forget, this pipe will be put on the main one, so the diameter should be a little larger.
Once you glue the two pipes together, all that remains is to insert the lenses. Install them as shown in the diagram. Fix them well so that they are not damaged during use.
VIDEO. How to make a telescope?
So, you have decided to make a telescope and are getting down to business. First of all, you will learn that the simplest telescope consists of two biconvex lenses - the objective and the eyepiece, and that the magnification of the telescope is obtained by the formula K = F / f (the ratio of the focal lengths of the lens (F) and the eyepiece (f)).
Armed with this knowledge, you go digging through boxes of different junk, in the attic, in the garage, in the shed, etc. with a clearly defined goal - to find more different lenses. These can be glasses from glasses (preferably round ones), watch magnifiers, lenses from old cameras, etc. Having collected a supply of lenses, start measuring. You need to choose a lens with a larger focal length F and an eyepiece with a smaller focal length f.
Measuring focal length is very simple. The lens is directed at some light source (a light bulb in the room, a lantern on the street, the sun in the sky or just a lit window), a white screen is placed behind the lens (a sheet of paper is possible, but cardboard is better) and moves relative to the lens until It will not produce a sharp image of the observed light source (inverted and reduced). After this, all that remains is to measure the distance from the lens to the screen with a ruler. This is the focal length. You are unlikely to cope with the described measurement procedure alone - you will need a third hand. You'll have to call an assistant for help.
Once you have selected your lens and eyepiece, you begin constructing the optical system for magnifying the image. You take the lens in one hand, the eyepiece in the other, and through both lenses you look at some distant object (not the sun - you can easily be left without an eye!). By mutually moving the lens and eyepiece (trying to keep their axes on the same line), you achieve a clear image.
The resulting image will be enlarged, but still upside down. What you are now holding in your hands, trying to maintain the achieved relative position of the lenses, is the desired optical system. All that remains is to fix this system, for example, by placing it inside a pipe. This will be the spyglass.
But don't rush into assembly. Having made a telescope, you will not be satisfied with the image “upside down”. This problem is solved simply by a wrapping system obtained by adding one or two lenses identical to the eyepiece.
You can obtain a wraparound system with one coaxial additional lens by placing it at a distance of approximately 2f from the eyepiece (the distance is determined by selection).
It is interesting to note that with this version of the reversing system, it is possible to obtain greater magnification by smoothly moving the additional lens away from the eyepiece. However, strong magnification You won’t be able to get it if you don’t have a very high-quality lens (for example, glass from glasses). The larger the lens diameter, the greater the magnification obtained.
This problem is solved in “purchased” optics by composing a lens from several lenses with different refractive indices. But you don’t care about these details: your task is to understand the circuit diagram of the device and build the simplest working model according to this scheme (without spending a penny).
You can obtain a wraparound system with two coaxial additional lenses by positioning them so that the eyepiece and these two lenses are spaced from each other at equal distances f.
Now you have an idea of the telescope design and know the focal lengths of the lenses, so proceed to assembly optical device.
Well suited for assembling PVC pipes of various diameters. Scraps can be collected at any plumbing workshop. If the lenses do not fit the diameter of the tube (smaller), the size can be adjusted by cutting rings from a tube close to the size of the lens. The ring is cut in one place and put on the lens, secured tightly with electrical tape and wrapped. The tubes themselves are adjusted in the same way if the lens is larger than the diameter of the tube. Using this method of assembly you will get a telescopic telescope. It is convenient to adjust the magnification and sharpness by moving the sleeves of the device. Achieve greater magnification and image quality by moving the wrapping system and focusing by moving the eyepiece.
The process of making, assembling and customizing is very exciting.
Below is my telescope with 80x magnification - almost like a telescope.
Eyeglass lenses are a good material for a quality telescope. Before you buy good telescope, you can make it yourself from inexpensive and available funds. If you or your child want to get interested in astronomical observations, then the construction homemade telescope will help you study both the theory of optical devices and observational practice.Despite the fact that a refracting telescope built from spectacle glasses will not show you much in the sky, the experience and knowledge gained will be priceless. Afterwards, if you are interested in telescope construction, you can build a more advanced reflecting telescope, for example Newton’s system (see other sections of our website).
There are three types of optical telescopes: refractors (a lens system as a lens), reflectors (a lens - a mirror), and catadioptric (mirror-lens). All modern largest telescopes are reflectors; their advantage is the absence of chromatism and possible large sizes lens, because the larger the diameter of the lens (its aperture), the higher its resolution, and the more light is collected, and therefore the fainter astronomical objects are visible through the telescope, the higher their contrast, and the greater magnifications can be applied.
Refractors are used where high precision and contrast are required or in small telescopes. And now about the simplest refractor, with a magnification of up to 50 times, with which you can see: the largest craters and mountains of the Moon, Saturn with its rings (like a ball with a ring, not a “dumpling”!), bright satellites and the disk of Jupiter, some stars invisible to the naked eye.
Any telescope consists of a lens and an eyepiece; the lens builds a magnified image of the object that is viewed, then through the eyepiece. The distance between the lens and the eyepiece is equal to the sum of their focal lengths (F), and the magnification of the telescope is equal to Fob./Fok. In my case it is approximately 1000/23 = 43 times, i.e. 1.72D with an aperture of 25 mm.
1 - eyepiece; 2 - main pipe; 3 - focusing tube; 4 - diaphragm; 5 - tape that secures the lens to the third tube, which can be easily removed, for example, to replace the diaphragm; 6 - lens.
As a lens, let's take a blank lens for glasses (can be bought at any "Optics") with a power of 1 diopter, which corresponds to a focal length of 1 m. Eyepiece - I used the same achromatic coated gluing as for the microscope, I think for this simple device- this is a good option. As a body, I used three tubes made of thick paper, the first about a meter, the second ~20 cm. The short one is inserted into the long one.
The lens - the lens is attached to the third tube with the convex side facing outwards, a disk is installed immediately behind it - a diaphragm with a hole in the center with a diameter of 25-30 mm - this is necessary, because a single lens, and even a meniscus, is a very bad lens and for obtaining of tolerable quality, you have to sacrifice its diameter. The eyepiece is in the first tube. Focusing is done by changing the distance between the lens and the eyepiece, moving the second tube in or out, focusing conveniently on the Moon. The lens and eyepiece must be parallel to each other and their centers must be strictly on the same line; the diameter of the tube can be taken, for example, 10 mm larger than the diameter of the aperture hole. In general, when making a case, everyone is free to do as they wish.
A few notes:
- do not install another lens after the first one in the lens, as advised on some sites - this will only cause light loss and deterioration in quality;
- also do not install the diaphragm deep in the pipe - this is not necessary;
- it’s worth experimenting with the diameter of the diaphragm opening and choosing the optimal one;
- you can also take a lens of 0.5 diopters (focal length 2 m) - this will increase the aperture opening and increase the magnification, but the length of the tube will become 2 meters, which may be inconvenient.
A single lens is suitable for the lens, the focal length of which is F = 0.5-1 m (1-2 diopters). It's not difficult to get; it is sold in an optical store that sells glasses lenses. Such a lens has a whole bunch of aberrations: chromaticism, spherical aberration. Their influence can be reduced by using lens aperture, that is, reducing the entrance aperture to 20 mm. What's the easiest way to do this? Cut a ring out of cardboard equal to the diameter of the pipe and cut the same entrance hole (20 mm) inside, and then place it in front of the lens almost close to the lens.
It is even possible to assemble a lens from two lenses in which the chromatic aberration that appears as a result of light dispersion will be partially corrected. To eliminate it, take 2 lenses different shapes and material - collecting and scattering - with different dispersion coefficients. A simple option: buy 2 spectacle lenses made of polycarbonate and glass. IN glass lens the dispersion coefficient will be 58-59, and in polycarbonate – 32-42. the ratio is approximately 2:3, then we take the focal lengths of the lenses with the same ratio, say +3 and -2 diopters. We add these values and get a lens with a focal length of +1 diopter. We fold the lenses tightly; the collective should be the first to the lens. If it is a single lens, then it should have the convex side facing the object.
How to make a telescope without an eyepiece?! The eyepiece is the second important part of the telescope; we would be nowhere without it. It is made from a magnifying glass with a focal distance of 4 cm. Although for the eyepiece it is better to use 2 plano-convex lenses (Ramsden eyepiece), setting them at a distance of 0.7f. Perfect option– remove the eyepiece from the ready-made instruments (microscope, binoculars). How to determine the magnification size of a telescope? Divide the focal length of the lens (for example, F=100cm) by the focal length of the eyepiece (for example, f=5cm), you get 20 times the magnification of the telescope.
Then we need 2 tubes. Insert the lens into one, and the eyepiece into the other; Then we insert the first tube into the second. Which tubes should I use? You can make them yourself. Take a sheet of whatman paper or wallpaper, but be sure to have a thick sheet. Roll the tube to fit the diameter of the lens. Then you fold another sheet of thick paper and place the eyepiece (!) tightly into it. Then insert these tubes tightly into each other. If a gap appears, wrap the inner tube in several layers of paper until the gap disappears.
Now your telescope is ready. How to make a telescope for astronomical observations? You simply blacken the inside of each pipe. Since we are making a telescope for the first time, we will use a simple method of blackening. Just paint the inside of the pipes with black paint.The effect of the first telescope created independently will be stunning. Surprise your family with your design skills!
Often the geometric center of the lens does not coincide with the optical center, so if you have the opportunity to have the lens sharpened by a specialist, do not neglect it. But in any case, an unground spectacle lens blank will do. Lens diameter of great importance does not exist for our telescope. Because spectacle lenses are highly susceptible to various obberations, especially the edges of the lens, then we will aperture the lens with a diaphragm of about 30 mm in diameter. But to observe different objects in the sky, the aperture diameter is selected empirically and can vary from 10 mm to 30 mm.
For an eyepiece, of course, it is better to use an eyepiece from a microscope, level or binoculars. But in this example I used a lens from a point-and-shoot camera. The focal length of my eyepiece is 2.5 cm. In general, any positive lens of small diameter (10-30mm) with a short focus (20-50mm) is suitable as an eyepiece.
Determining the focal length of the eyepiece yourself is easy. To do this, point the eyepiece at the Sun and place a flat screen behind it. We will zoom in and out of the screen until we get the smallest and brightest image of the Sun. The distance between the center of the eyepiece and the image is the focal length of the eyepiece.
The spyglass has centuries-old history. For tens of centuries, this object has made it possible to observe long-range objects. How many new geographical discoveries owes it to this optical device! In the age of advanced technology, it has not lost its practical value. The specialized market offers an abundance of all kinds of options for modern optical devices. You don't have to spend money on them. Below we will talk about how to make a telescope at home.
Creative process
Before you begin, you need to purchase components for the future optical device. You will need:
- a pair of lenses;
- thick cardboard;
- epoxy resin or nitrocellulose-based glue;
- black matte dye;
- wooden template;
- polyethylene;
- scotch;
- scissors;
- ruler;
- brush for applying glue;
- simple pencil.
Making a telescope at home requires some preparation and understanding of the operating principles of this optical device. Like the factory one, homemade pipe consists of two or more mobile parts that regulate the distance between the lens and eyepiece. Adequate work requires mandatory compliance with the optical axis. Therefore, the retractable parts must fit snugly against each other.
Glasses for glasses can be used as lenses. Diopters should be varied. Choose a positive lens with a diameter of 5 cm and a value of 6 diopters. The diameter of a negative lens with a value of 21 diopters should not exceed 3 cm. You can use a long-focus lens from a camera that has outlived its age, or an old magnifying glass.
The positive lens is used as a peripheral lens, and the negative lens, called the eyepiece, is located closer to the eye. Instead of a negative lens, you can use a short-focus positive lens. But in this case, the length of the pipe should be increased, the image will be upside down.
To avoid the risk of fogging internal cavity, you should pay attention to the tightness of the pipe. It is not recommended to get carried away with large magnifications. In a homemade optical device, powerful lenses can significantly reduce image quality.
Algorithm of actions
Summarize! A do-it-yourself spyglass and its manufacture require a lot of perseverance and even more accuracy. With some effort, you can create a beautiful and useful optical device that will not only serve you well, but will bring true satisfaction!
If you weren’t able to make a spotting scope yourself, we recommend going to the section and choosing the appropriate model.