Rare Vintage 1974 Questar 3. 5 " Standard Telescope - Many
Item History & Price
The Questar 3.5” entered commercial production in 1954 with ads for the model run in many astronomy, science, photography, and nature related magazines such as National Geographic, Scientific American and Sky & Telescope. The ads focused on the telescope's mechanical and optical design, educational value for children, ease of use, and adaptations as a spotting scope and telephoto lens. Note: I am also offering separately a Gitzo heavy-duty tripod that I used for this telescope. It makes a great companion for this telescope because it's rock solid and provides a very stable telescope platform. It is in a separate listing that started at the same time as this listing. In the tripod listing there is also a photo of the Questar on the tripod (I hit the max number of photos for this listing). See my current listings (use the "me" link or "seller information" above, then click on "items for sale"). Built-in features:Diagonal erecting prism Barlow lens (for double magnification) switches in and out Sidereal synchronous electric clock drive Clamps for altitude and declination adjustments. Finder scope. Finder sun filter switches in and out. Barrel has perpetual star chart that slides forward to form a dew cap. Moon chart engraved on barrel, under star chart Standard Accessories Included:Leather, velvet-lined, compartmented case Polar-equatorial table-top legs Two eyepieces: 16mm (80-130x) and 24mm (50-80x) Partial aperture solar filter Lens cap Power cord for electric drive Sliding dew cover with star chart engraved Moon chart under dew cover Original instruction book (1973 version), color Questar brochure (1972 version), b&w Questar "Instruments and Accessories" catalog with price list (1978 version), flyer "On the problem of choosing a telescope" (1973 version). Additional Optional Accessories Included:Vinyl "Naugahyde" slip-on protective cover (goes over leather case). Full aperture solar filter in wooden case Piggy-back camera mount (for mounting a camera on top of the telescope) Camera counter-weight 8mm Questar Brandon eyepiece 12mm Questar Brandon eyepiece 32mm Questar Brandon eyepiece Additional separate 2x Barlow lens Specifications:TYPE: Maksutov Cassegrain Catadioptric. No coma, astigmatism or spherical aberrations.
CLEAR APERTURE: 3.5 inches, 89mm (Center Obscuration, 27.9mm)
FOCAL LENGTH: Basic Visual 50.5 inches, f/14.4, 1300mm
FINDER LENS: 4" Fl., 4x and 8x, Field 12° and 8°
POWERS: Powers are eyepiece dependent and can range from 40x to 270x with Questar Brandon eyepieces
POWERS LIMIT: Resolves 1 sec. Arc at 50feet EFL
LENS: BK7, MgFl2 coated, passes UV to 3300 A, IR to 1 micron, parfocal
AMPLIFYING/BARLOW LENS: Minus 43.9 mm FL
ERECTING SYSTEM: Star Diagonal type, 90° BK7, MgFL2 coated
BARREL ASSEMBLY: Barrel: forged aluminum, machined full length
LENS CELL: Aluminum 24S-T4, black anodized
REAR CLOSURE PLATE: Stainless steel CENTRAL TUBE - precision machining and alignment after assembly.
DEWCAP: Internally black-flocked Synthane seamless tube 1/32" thick, to which is bonded a pre-rolled aluminum sheet
FOCUSING MECHANISM: Mirror thimble, stainless steel sliding tube. Slides on stainless, fixed, light-baffle
tube, with front-end insert tube of .010" wall thickness. Conical ss spring-loaded. Focus
rod ss 303, ground shaft, 56 T.P.I. precision ground threads
KNOBS: Aluminum 24S-T4, corrosion-resistant, hand-turned on turret lathe, stainless steel shafts and levers
EQUATORIAL MOUNT: Aluminum sand casting, virgin alloy 356-T6 heat treated. Tool room hand-turned and polished.
Highly corrosion-resistant. Jig-bored and precision threaded for legs. Bottom flange 7" o.d. Fits tripods with 1/4-20 threads
TURNTABLE OR LOWER FORK BASE: Sand casting same alloy, toolroom turned, jig-bored and precision-reamed, aircraft
polyurethane painted
LEGS: Aluminum 61 S-T3, centerless-ground and threaded, anodized. Center leg adjustable. Butyl rubber tips
SYNCHRONOUS DRIVE MOTOR: 110V. 60 cycles. Sealed, lubricated gear train, 2.7 watts
RIGHT ASCENSION GEAR: Bronze, 4" diameter, and 4" diameter teflon-facing bearing surfaces
SIDE ARMS, INNER FORK BRACKETS, CONTROL BOX: Die castings of corrosion-resistant aluminum alloy 13, toolroom
turned, milled, jig-bored, tapped and reamed. Special painted aluminum and clear-urethane protected
FINDER MIRROR CAGE: stainless steel, brushed satin finish
ALTITUDE OR DECLINATION CIRCLE: 3-15/16" diameter, 301 s.s., cemented and riveted to bracket ring assembly, 10
divisions with etched and filled markings
CLAMP: Bakelite padded s.s. stud clamps dec. circle to side arm
AZIMUTH OR R. A. CIRCLE: 6" diameter, anodized aluminum, silk-screened, graduated to 10 and 4 min of time. May be set as
celestial clock. Manual slow-motion independent of drive
SLOW MOTIONS: Continuous 360 degree rotation, safety clutch held. Permits control to a few seconds of arc. Absolutely free of
backlash, lag, or play. Ratio 31 to 1
DIMENSIONS: Height, upright, 14". With barrel horizontal, 11" high and long. Weight, 6.7 poundsThis is bulky and awkward to pack for shipping, hence high shipping cost.I will accept payment via PayPal. Buyer pays flat shipping and insurance fee. Returns accepted.