Tele Vue Starbeam with bar and bracket for SCT mounting.
Starbeam is a precision unit power finder designed to make pointing your astronomical telescope easy. Viewing through Starbeam, a transparent "red-star" appears projected against the sky background. The "star" is actually a small pinhole illuminated by a red L.E.D. Placed at the focus of a beam-splitting mirror/lens, the star is projected to infinity. Starbeam is effectively a reverse Herschelian telescope.
The size of the pinhole and focal length of the mirror result in a 10 arc-minute red-star, and 1/3 the diameter of the moon. Its size, color and adjustable brightness make it easy to see against any twilight to dark sky background. With a mirror aperture of 39mm, the projected image can be easily seen at any distance behind the mirror, whether 2 inches or 2 feet! Because the mirror surface is uncoated, and a multi-coated compensating curve is designed into the back of the mirror, the normal sky background appears through the almost invisible "mirror-lens".
This new Starbeam model has a dovetail bar and mounting bracket that fits the rear cell of any 8” or larger SCT. The bar and bracket are also sold separately so any Starbeam owner can adapt the uniquely accurate, large aperture 1x finder to SCT models.