Here is a handy item to keep in your wallet. It provides telescope optics formulae on one side, and instructions for precise polar alignment for your equatorial mount using the star drift method on the other side. When you need it you need it!
Click the links below to open this handy reference card in various formats. Use your own photo or printing software to print the images in a business card size. Cut them out, place them back-to-back, and laminate them together with clear shipping tape.
