Astronomy
The
Collimation - this French web page (in English) is the best information I've
found on the Internet for SCT collimation. I follow this procedure for daytime
collimation using a 5/8" ball bearing as an artificial star.
Mark Kaye's
Telrad Heater - this Telrad modification really works, is non-intrusive, and can
be used with a Kendrick controller.
Rocket
Crawford's Knife-Edge Focusser - detailed design and step-by-step instructions
for building a 35mm camera body focusser that really works. If you have an Olympus
OM-1 body, like many astrophotographers, you can use an OM-10 body for the knife-edge
focusser. They're the same size and dead OM-10s are easier to find than OM-1s.
I found one for only $10 at a used camera store and he had others.
University of Arizona's
Messier Catalog - a great observing resource. Plug these images right into
astronomical software.
Richard
Robinson's Globular Cluster Index - another great observing resource.
U.S. Naval Observatory
Astronomical Data - sunrise, sunset, moonrise, moonset, lunar phases, and lots
more.
