Engineering a Telescope

To construct a telescope two convex lenses are required which are thicker in the middle. An appropriate mounting is also required for this, as a rule from the two lenses which are to be used the objective lenses should be large and fairly weak, and the eyepiece through which viewing takes place should be smaller and stronger.

An eye piece of with a focal length of 2-3 centimeters should be used and an objective lens with a focal of 25 to 50 centimeters.

The lenses are usually mounted in two tubes which can be slid up and down in order that the telescope can focus. A good material to use for the two tubes is stainless steel pipe (Edelstahlrohre) and some pipe clamps (Rohrschelle). To determine the distance between one lens and the other it is recommended that you hold the smaller lens to your eye, hold the larger lens in front of the smaller one and try to focus on an object in the distance, when the object become clear then this should be regarded as the correct amount of distance.

Epoxy can be used to hold the lenses firmly in place, but try to make sure that you don’t get this on the lenses as this will obscure full and clear vision. The lenses should be aligned with one another so that they are both set within the same plane both horizontally and vertically (centre to centre) before fixing them both in place. When finished look through the telescope, if you see a partial image or no image at all then the lenses are not aligned properly.

The finished product will be more than adequate for viewing the moons surface and for star gazing at some of the stars nearer to earth. It is not recommended that you look directly at the sun with it as this can seriously damage your eyes.

The telescope described above uses two convex lenses which create an upside down image, which really doesn’t matter that much if you are star gazing or looking at the moon. If you were to use rectifiers this would then change the image to the right way round, these are used in binoculars. If you were to use rectifiers in your telescope you would be sacrificing the power and the ability to view a further away object.

When you have finished your telescope there are a number of planets you can look out for in the solar system which are Pluto, Neptune, Uranus, Saturn, Jupiter, Mars, Venus and Mercury. All of the planets within the solar system orbit the sun. The solar system was created billions of years ago before people ever existed. The sun is the only star that astronomers can see up close.

I am sure that when you have created your telescope you will spend many nights gazing at the stars. The moon which can often be seen day and night is a good object to start with. Once you have the focus right on your telescope the possibilities when using your telescope will be endless. Why not invest in a book on astronomy to get you started then you will have an idea of just what you are looking at through your newly engineered telescope.