To see objects through a telescope it must be pointed to exactly the
right spot. The Telrad is sight for pointing telescopes to that
″right spot″.
Through a Telrad you see the sky the way the star charts show it.
Not a small unside-down and magnified portion of it, but the
″real sky″ with three lighted target rings set against
it. The large ring is 4 degrees across. It outlines the area covered
by a finderscope. The small ring is 1/2 degree across and outlines
the area seen in the telescope.
