Astronomical Telescope

A simple model to show the principles of the astronomical telescope, which produces an inverted image. Comprising a plano-convex lens 38 mm dia x 150 mm focal length, mounted in a tube 400 x 50 mm dia, and a double convex lens 50 mm dia 500 mm focal length, mounted in a tube 400 x 55 mm dia approx. The small tube is located in the large tube by means of foam plastic rings, for effective sliding.