QUESTAR 50TH ANNIVERSARY 3-½ TELESCOPE
The Telescope: The Questar is an elegant high performance telescope which combines high technology optics with many convenience features. The 50th Anniversary 3-½ model is a fully instrumented telescope where the 3 lb. (1.4 kg) Optical Tube Assembly is attached to a Fork Mount to facilitate use for terrestrial applications, and it can be configured as an astronomical tracking platform too.
The Questar 50th Anniversary telescope differs from production models in ways designed to make this a distinct instrument for the connoisseur:
- The Moon Map, the Star Chart, and the Right Ascension Setting Circle are etched and silk screened as was done on the original Questars of 1954. This gives a three dimensional feel and appearance lacking by the modern production telescopes.
- The Primary Mirror is made of Quartz (Fused Silica) for thermal stability, with enhanced protected Silver reflective coatings.
- The Corrector Lens is made of the usual Borosilicate Crown, but with a durable Magnesium Fluoride antireflection coatings on both front and rear surfaces.
The optics are the best ever made for the Questar, hand figured to an incredibly high standard. Each set is professionally certified across the full aperture by an accompanying Zygo GPI interferogram showing:
- Readout of Peak to Valley (PV)
- Readout of Root Mean Square (RMS)
- Surface Wavefront Map (peaks and valleys)
- Oblique Plot (peaks and valleys)
- Surface Wavefront Profile (height and distance)
- Intensity Map
- Measurement Attributes
* On the Lens Cover, Fork Arms and left side at rear of the Barrel are special 50th Anniversary Model logos.
* The Questar Powerguide II Drive and Corrector is installed, this is an option for other Questars.
* The Full Aperture Solar Filter is provided, this is an option for other Questars.
* The telescope is delivered within the Questar Deluxe Leather Carrying Case, this is an option for other Questars.
* A personalized Certificate of Authenticity, signed by the owner and CEO of Questar is provided.
* A second document is provided that is signed by all the of Questar Corporation.
* Questar 50th Anniversary Telescope bears a serial number with the prefix "50TH" and suffix "SQTZ" indicating it is special.
The Questar 3-½ telescopes incorporate the Questar Control Box which is engineered and refined to provide reliable convenience and safety features. This housing at the rear of the telescope provides two viewing or imaging ports (at top or axial), with control levers and linkages providing quick flick knob selection.
This arrangement provides three magnification (power) changes per eyepiece:
1. Internal Finder of 100mm EFL. Magnification = 100 divided by focal length of eyepiece
2. Low Magnification at Prime Focus. Magnification = 1280 divided by focal length of eyepiece
3. High Magnification. Provides about 2X magnification when observing through the telescope; not use able with the Finder.
For example one may use the 24mm Brandon eyepiece with the Finder at 4X, then select to look through the telescope at 50X, and then increase the magnification to 80X or more by dialing in the Barlow*. Observing through the any of the three magnifications can be achieved and changed without the observer ever moving away from the eyepiece!
* The provided telescope Barlow is approximately 2X, we have seen a range over the years of from 1.6 to more than 2X. Company Seven's testing process measures it exactly, and we provide the information to our customers so that they may make better choices of eyepieces.
The equatorial fork mount is made of a brushed cast aluminum which is then lacquered with a clear coat. Each of both axes has a manual friction drive control, the Right Ascension also having slip clutch permitting manual override of the tracking motor. The mount includes the Powerguide II clock drive system useable world wide portable with a 9 volt battery, driven Right Ascension setting circle, Declination setting circle, Declination axis variable clutch lock. The drive is smooth enough to provide flawless tracking of celestial objects for visual applications, although the telescope can easily be accessorized to introduce one into most types of film or CCD astrophotography.
The Questar telescope stores into a furnished compact leather clad carrying case (easily "carry on luggage") that has pockets sewn in the liner to accommodate the included tabletop tripod legs, an extra eyepiece, the solar filter, and AC adapter cord. There is also a pocket for the optional Powerguide Controller for worldwide 9 volt D.C. battery powered operation.
When you wish to use your Questar 3-1/2 astronomical telescope in the backyard or at a location with no convenient platform to set up the provided tabletop tripod, we recommend you consider a third party good quality rigid field tripod. Or for even better convenience, consider our Questar Tristand. The Tristand is a refined, compact telescope equatorial platform and pier that places the Questar 3-1/2 eyepiece at about a comfortable 41 inch (105 cm) height. A taller Astropier is also available. The Astropier and Tristand are suitable for use in latitudes from 26 to 90 degrees, or 4 degrees with the optional Wedge.
|Weight of Telescope without Lens Cover and Eyepiece:
||7 lbs. 7.4 Oz.
|Weight of Telescope with Lens Cover and Eyepiece:
||7 lbs. 11.8 Oz.
* Specifications are subject to change without notice.