Telescope costs and cost reduction

The prices of more than 60 telescopes of the most diverse types and sizes are analyzed according to telescope aperture. Actualized prices in 1995 were calculated taking inflation into account, as well as fluctuations in the DM exchange rate. We discuss the dependence of prices on factors like size, mass, optical system, number of construction parts (similarity laws), as well as on special technical requirements. The relationship between telescope aperture and costs shows interesting differences between the classical astronomical telescopes and the new, large telescope projects. The number of repeated construction parts and the number of realized instruments with the same design is of great importance. Cost reductions are best achieved in the conception and design phase of telescope development.