Observing solar eclipses by projection through a refractor telescope is a great fun. It is safe and very simple to carry out!

A telescope has a very important advantage over the pinhole camera: a telescope projects a beautiful, much larger image of the Sun than that projected through the pinhole camera.

A small refractor is rather recommended for this purpose. It is portable and will meet our requirements of a bright, fairly big solar image projected on a screen of white cardboard or paper.

Observing the Sun by projection through a reflector telescope, i.e., the type of telescopes whose objective is a concave mirror, is not recommended. Exposing the telescope's mirror to the Sun for even a fraction of a second may damage the optics of the telescope.

A refractor whose objective lens is 6-8cm in diameter is an excellent choice. Actually, these are the sizes of refractors with which the PSC will observe the coming total solar eclipse of 29 March 2006.

Even small refractors of 3-5cm aperture will perform very satisfactorily.

Fig (1)

The refractor telescope of the PSC

Hold the screen in one hand behind the eyepiece of the telescope.

With your back to the Sun, aim the telescope to the Sun. This can be done easily by observing the shadow of the telescope while slewing it to the Sun. When the size of the telescope's shadow is minimum, then the rays of the Sun will be passing through the telescope and the solar image will be projected on the screen. You don't have to look at the Sun to aim the telescope.

Move the screen back and forth from the eyepiece. You will notice that when the screen moves away from the eyepiece, the image of the Sun becomes larger and fainter.

Position the screen at an appropriate distance to obtain a solar image of suitable brightness and size.

Never place your hand between the eyepiece and screen!