Astroscan

The Astroscan was a wide-field 4⅛" clear-inch (105mm) diameter reflecting telescope, originally produced by the Edmund Scientific Corporation, that was for sale from 1976 to 2013.

The Astroscan had a Newtonian reflector layout with a 4⅛" clear-inch (105mm) diameter f/4.2 aluminized and overcoated borosilicate glass parabolic primary mirror with a focal length of 17½ inches (445mm).

[2][3] Rather than using a more traditional equatorial or altazimuth mount the Astroscan features a spherical housing around the primary reflector which sat in a cast aluminum cradle.

[1] The telescope body was made from high impact acrylonitrile butadiene styrene (ABS) plastic and was equipped with a carrying strap to aid portability.

Because it was targeted at the novice market the telescope had its limitations: The general design was for low power hand-held or wide-angle work, the short f/4 focal ratio did not allow for high magnification without the image degrading,[4] and the primary mirror was factory aligned with no provisions for adjustment.