Finally, the french best-seller available in english
A book by Jean-Marc Lecleire
This is the first comprehensive mirror-making manual to appear in the English language in over 40 years. The theme of this book is the fabrication of both the optics and mechanical parts for three different telescopes. The first is a Newtonian with a 130-mm f/9.2 primary mirror.It is especially designed for beginners, being both inexpensive and easy to make. The second instrument is also a Newtonian reflector with a 250-mm f/4.3 primary mirror. This is an “all purpose telescope”which can provide a lifetime of viewing pleasure. The third instrument is a 300-mm f/12 Cassegrain-coudé (or Nasmyth). This a project for the advanced telescope maker and features a long-focal-length mirror, a convex secondary, and a telescope window.
This book is arranged into four parts. The first is devoted to the basics of optical glass working: grinding, polishing, testing and correcting (figuring). The remaining three parts deal with the specific steps needed to build each of the three telescopes described above. The text is augmented with more than 225 pictures and drawings. A noteworthy departure from other books is the detailed instructions the authors provide for corrective measures to cure optical difficulties encountered during figuring. It also deals more thoroughly than previous books with figuring the kind of mirrors used today with fast Newtonians or Cassegrain primaries. The authors discuss tests less cumbersome than the Foucault test in figuring these very fast instruments, namely the wire and caustic tests.