It is difficult to find a person on the whole earth who was not at least a little interested in astronomy. This, of course, requires the presence of a certain tool, which would allow a closer look at the mysteries of the starry sky. If there is a telescope or binoculars, then this is enough to admire the beauty of the starry sky. But in the presence of strong interest, such devices cannot satisfy the request. Something more powerful, that is, a telescope, is needed. But how to create it? Consideration of the question: " How to make a telescope with your own hands?" and this article is devoted.
Introductory information
Purchasing a factory-made telescope will be quite expensive. Therefore, its purchase is appropriate in cases where there is a desire to engage in astronomy at least at an amateur level. But first, in order to get basic knowledge and skills, and also to understand whether this science really seems to be what most people think about it, it would be useful to create a home-made home telescope with your own hands. In many children's encyclopedias and various popular science publications you can find a description of the process of manufacturing a simple device that allows you to see craters on the moon, the disk of Jupiter along with its four satellites, the rings and Saturn itself, the sickle of Venus, individual bright and large star clusters and nebulae. It should be noted that the weak point of such devices is the image quality, which cannot compete with factory-made devices.
Bit of theory
Before you begin to create a telescope with your own hands at home, you should understand how this device works.
Two minimally necessary optical nodes are a lens and an eyepiece. The first is conceived in order to collect light. What is the maximum magnification of the finished device, and how poorly visible objects can be observed, depend on its diameter. The eyepiece is needed to enlarge the image, which is formed by the lens and to transmit the image to the human eye.
Defining type
Depending on the device, different telescopes are distinguished. The two most common types are reflectors and refractors. In the first case, a mirror acts as a lens, in the second - a lens system. At home, creating everything in the required quality for the reflector is quite problematic, due to the complexity and accuracy of the manufacturing process. Whereas refractor lenses are easy to purchase at an optics store. As you can see, the difference between them is purely in design.
First trial
To determine the magnification value, the ratio of the focal length from the lens to the eyepiece is used. The scheme discussed below will provide an improvement in visual properties by about 50 times.
Initially, it is necessary to stock up on a blank lens for glasses, the strength of which is one diopter. This corresponds to a focal length of one meter. Usually their diameter is about 7 centimeters. This is just what is needed for the lens. It should be noted here that if you are interested in how to make a telescope with your own hands out of lenses for glasses, it should be recognized that they are poorly suited for such inappropriate use. But you can use them if you wish. If there is a telephoto biconvex lens, then it is better to use it. Although the magnifying glass of a magnifier with a diameter of 3 centimeters or a lens from a microscope is also suitable for the role of an eyepiece.
For the body, two pipes must be made of thick paper. The first (representing the main part) will have a length of one meter. For the eyepiece, a tube of twenty centimeters is created. The short is inserted into the long. To make the case, you can use a wide sheet of whatman paper or a roll of wallpaper, turning them into a pipe in several layers and glue the PVA. The number of layers is selected manually. It is necessary to achieve the stiffness effect of the future device. The inner diameter of the main part should be equal to the size of the selected lens.
But that's not all
If the only question is how to make a telescope with your own hands at home, then you can do only the above.
But for a better result, you can not do without some nuances.
So, the lens must be mounted in the first tube outward with a convex side using a frame. For this, rings of a comparable diameter with a thickness of a centimeter are suitable. Immediately after the lens, you must install the disk - aperture. Its specific difference is the presence in the center of the hole with a diameter of 2.5–3 centimeters. This is necessary to reduce the distortion of the image that forms a single lens. True, this approach reduces the amount of light that collects the lens. To improve the result, the lens must be installed as close to the edge of the pipe as possible. Then comes the turn of the eyepiece. Where to place it? It is required to install it in the ocular node as close to the edge as possible. At the same time, the cardboard mount is ideal for the eyepiece. The device is best done in the form of a cylinder, the diameter of which is equal to the size of the selected lens. It is installed inside the pipe thanks to two fasteners (for example, disks). At the same time, it is necessary to ensure that it is commensurate in diameter with both the lens and the ocular site.
Preparing the telescope for use
The device focuses by changing the distance between the lens and the eyepiece. This is achieved, in a mechanical sense, by ensuring the movement of the ocular site located in the main tube. To fix the position it is best to use the force of friction. It should be noted that it is more convenient to focus on large and bright objects, such as nearby buildings, the moon, bright stars (but not the sun).
When creating a telescope, it should be borne in mind that the lens and the eyepiece should be parallel to each other, and their centers should be located on the same line. At the preparation stage, you can experiment with the diameter of the diaphragm opening in order to find the optimal one. So, for example, if you select a lens at 0.6 diopters and set the focal length to 1.7 meters (1 / 0.6), then this will allow for a larger increase. True, this will have to work on the aperture. Namely, to increase its size.
And after completing work on the first device, remember one simple truth: you can look at the Sun only two times through a telescope - first with your right eye, then with your left. Such a dangerous occupation instantly hurts your eyesight, so it is better not to do it.
Subtotal
It should be noted that the resulting design will be imperfect. Namely, she will give an inverted image. To fix this, it is necessary to use another collecting lens with the same focal length as the eyepiece. It is installed in a pipe near it. It would seem that now there should be no questions on how to make a telescope with your own hands with magnification. But this is far from the only true approach.
You can use other schematic options, taking as the basis of the lenses of glasses or telephoto lenses. This is a very broad area, in which there are both completely green beginners and professional astronomers. Therefore, if a specific question arises or a misunderstanding of something, you should not be shy, calmly ask a question of interest. To do this, today there are thematic circles, sites, forums, etc. After all, you just have to plunge into the world of astronomy - and you will see numerous treasures of the starry sky. In general, the considered practical information should be enough to create a simple device. If you want to construct and implement something more complex, then you can not do without quality theoretical training.
Required knowledge
It should always be remembered that the main characteristic is the size of the lens, eyepiece and focal length. These are alpha and omega, without which it is impossible to create a telescope. But at the same time, there are a large number of small points that can significantly affect the final result. For example, the maximum useful magnification of a telescope. The value of this parameter is equal to twice the diameter of the lens (in millimeters). It makes no sense to make a device with a large increase, since, most likely, it will not work to see new details. But the overall brightness of the image will suffer. Therefore, for devices with a fifty-fold increase, it is not recommended to use lenses less than 2.5 centimeters. It should be noted that the option proposed above has indicators of 7 and 3 cm, which is well suited for a telescope with a quality of 50x. You can take a 4-cm lens as a lens, but in this case, the resolution of the optical device decreases. Therefore, it is better to use the recommended values.
Design Experimentation
The option, when the main pipe per meter is created, and an additional twenty centimeters are embedded in it, is far from all. You can adjust the design in order to create other forms of telescopes. For example, a tube of 60–65 centimeters is used for the lens, and another 10–15 cm is included in it, for the eyepiece, whose length is 50–55 cm.
Back to theory
The minimum value of the effective magnification for a telescope depends on the diameter of the eyepiece. There is one very important nuance here! Its size should not exceed the diameter of the fully opened pupil of the observer. Otherwise, not all the light collected by the telescope will reach the eye: it will be lost, impairing the quality of the device. So, the maximum diameter of the pupil of the eye in an ordinary person does not exceed five to seven millimeters. Therefore, to find the minimum useful increase, 10 times is taken (aperture times 0.15). This interesting word, aperture, means a hole similar to the diaphragm, only slightly improved and advanced. This device is used in complex devices to obtain a high-quality result. But this is already for those who want to make a telescope with their own hands at home with serious characteristics for a more thorough study of the starry sky.
Conclusion
Well, here is the minimum that everyone needs to know in order to create their own device for studying the starry sky. It doesn’t matter what the first step will be - assemble a do-it-yourself telescope-reflector or a refractor. The main thing, if this is of interest, it is necessary to act in this direction - to learn, learn new knowledge, practice, discover something new for yourself or even for the whole world - do not stop, and luck is accompanied by purposeful ones.
But be aware that in the manufacture of devices with a larger magnification, diffraction phenomena will express themselves more strongly. This will result in reduced visibility. And finally, the task: what basic parameters should a telescope have, providing a 1,000-fold increase?