Questar 3½ in. CAT telescope

OBJECT TYPE: Lens
MANUFACTURER: Questar Corp.
NATIONALITY: American
PLACE MANUFACTURED: US, PA, New Hope
INTRODUCTION DATE: ca 1970
PRODUCTION DATES: ca 1970 -
ORIGINAL LIST PRICE: $1315.00 (standard)
FUNCTIONAL TYPE: catadioptric

NOTES:
  TYPE: Maksutov Cassegrain Catadioptric. No coma, astigmatism, or
  spherical aberrations.
  CLEAR APERATURE: 3.5 inches, 89mm.
  FOCAL LENGTH: Basic Visual, 50.5 inches, f/14.4, 1300mm.
  FOCAL LENGTH: Camera Close, 56 inches, f/16, 1400mm.
  FOCAL LENGTH: Camera with Ext. Tubes, 64inches, f/18, 1600mm.
  FINDER LENS, 4"Fl. 4x and 8x, Field 12 and 8 degrees.
  POWERS, 40-80x eyepiece, field 55 min-24 mm.
  POWERS, 80-160x eyepiece, fiels 42 min-16mm.
  POWERS LIMIT: Resolves 1 sec. arc at 50 feet EFL.
  FIELD OF VIEW, Photographic model, 1 degree, 30 minutes.
  LENS, BCS2, passes UV to 3300 A, IR to 1 micron, parafocal. Has
  negative FL minus 28 feet, 336" or 8500 mm.
  MIRROR, F2, Pyrex, or Cer-Vit. AlSio coated 3.800 dia.
  SPECIAL COATINGS: On Special order, broad-brand dielectric coating
  applied to Cer-Vit mirror, which increases its reflectivity. To both
  sides of front lensa VLR (very low reflection) coating is then applied
  which reduces the light loss at each surface to less than 1/10 of 1%.
  It transmitts all frequency of the visible spectrum and improves total
  light grasp by approximately 22%. Questar catalogue, 1972.

OBJECT IDENTIFIER: Q978.00001
BIBLIOGRAPHIC REFERENCE: George Eastman House Information File - Technology Collection.//