Checking and adjusting star diagonals

A diagonal mirror must also be checked and adjusted if necessary. Like any optical system in astronomy, accessories such as a diagonal prism or a diagonal zenith prism should direct the light beam centrally through the system. There are only a few ways to resolve this misalignment.

One of these is to place a thin strip of Teflon under the edge of the mirror. Depending on the design of the diagonal mirror, small springs can be attached under the mirror, and the adjustment can be performed using grub screws.

See also: http://www.teleskop-spezialisten.de/shop/Ueber-uns:::12.html