Astroscan

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An Astroscan wide-field Newtonian reflector.
An Astroscan wide-field Newtonian reflector.

The Astroscan is a wide-field Newtonian reflector telescope produced by the Edmund Scientific Corporation. It was designed by Norman Sperling to be used as an introductory telescope.[1] Rather than using a more tradition equatorial or altazimuth mount the Astroscan features a spherical housing around the primary reflector which sits in a cast aluminum cradle. The design is durable and allows for simple operation by novice amateur astronomers; it won an Industrial Design Award in 1976.[2] The telescope body is made from high impact ABS and is equipped with a carrying strap to aid portability.

[edit] Optical design

The Astroscan is a simple Newtonian reflector. It has a 4.25 in. 1/8 wave aluminized and overcoated borosilicate glass primary mirror with a focal length of 445 mm.[2] Because it is targeted at the novice market the primary mirror is factory aligned and there are no provisions for adjustment. The telescope's secondary mirror is mounted on an optical window at the front of the tube giving it the appearance of a catadioptric telescope, however the window is flat and does not contribute to the focal properties of the telescope. The Astroscan comes with 15 and 28 mm focal length eyepieces giving it a magnification of 30X and 16X respectively, with a 3.0° field of view using the 28 mm eyepiece.[2]

[edit] References