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.