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Price - $850.00

Ad Number: 101658

Posted: 24 Mar 2017

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Completely rare Quantum 100 spotting scope. For those not aware of the quantum story, here's the run-down:

Basically, it's something of a renegade Questar. This 4" Mak is just the OTA with a 1/4-20 tripod adapter and looks to be possibly a production prototype. According to the Company Seven history, "We are not sure if any of these telescopes were sold, but at least one was made and this appeared in OTI marketing literature." There is an S/N etched in the mounting plate that says "GH1004" - looks like this is #4.

Check the instruction manual here:
http://ralphfoss.com... 100 Series.pdf

I got this in 1985 and have taken good care of it. I just recently had it cleaned and serviced at Texas Nautical repair - they recommended NOT replacing the coatings in that they're still in good shape. No, they're not as bright as the current tech, but this is primarily a lunar/planetary and double star splitting scope. The optical figure of this instrument is exquisite - textbook diffraction patterns. The clear winner in resolving power in side-by-side "shootouts" with different Questar 3.5" scopes. It has a 6x30 finderscope attached.
It came in a 13x18x6 travel case - the foam is getting near replacement time. The build quality is superb. It weighs just over 6.7 pounds including the screw-in machined dust cap for the objective that is a hefty 11oz. The focuser is nicely tightened after the servicing.

For collectors, this is a superb bit of history for those collecting Questars. It's also no museum piece - it's a great grab & go. I include rings with a Vixen rail and a fairly new Thousand Oaks Optical sun filter I got for this.

Priced at $850 - FREE shipping to CONUS ONLY. Add 3% for PayPal.


  • Condition Used
  • Location Austin, Texas

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