APERTURE...THERE IS NO SUBSTITUTE.
Every telescope manufacturer says they use only "the best optics in the entire world". But if they really do, how come so many of their mirrors have to be re-figured? How come they have to be sent back twice from overseas for "touch ups"? Why do they have arrows drawn on their backs so that you have to install them in the direction that gravity helps hide their astigmatism? What good is an interferometry certificate if the mirror does not match, at all, the data presented to the owner? Who at the company decided that these mirrors were "good enough" and pushed them out the door? And the most important question of all: How is Webster Telescopes any different?
In the recent past, Dobsonian telescopes were crummy cardboard tubes, on flimsy particle board mounts, with "diffraction limited" (1/4 wave) optics. At least that is what the customer was told. Often these optics were less than 1/2 wave. This gave the Dobsonian telescope the reputation of being just a "light bucket"; slang for a scope that was gathering lots of light, but was sloppily spilling it into an optical mess. The Dobs were resigned to deep sky work, where low power, "diffraction limited" views were "good enough", and high power viewing was reserved for the Refractor telescopes.
Fast forward to today, Refractors are used mainly for astrophotography, and the Dobsonian telescope is the king of high power viewing. What event occurred that changed everything? Consistent, high quality mirrors became available to the industry. It seems simple, but when you look at mirrors from just a few years ago, you can't believe companies sold them as "diffraction limited" optics.
Don't waste your money, call around, ask on the forums, talk to everybody you can at a star party. Ask them what brand mirrors they have had to get re-figured. Ask guys who do re-figuring work, what famous "premium" brands come in again and again. For some real fun, ask the manufacturers themselves, how many of their mirrors, honestly, have been returned for re-figuring. You would not buy a car without reading about its reliability in Consumer Reports, PLEASE don't buy a telescope without checking this first!
Our smaller mirrors (20" and under) are made by master optician Carl Zambuto. Not only is Mr. Zambuto the undisputed champion of of his craft, but he is also a tireless instructor, passing the techniques on to the next generation.
For a few years we made no telescopes under 22" because there were simply no optics available to us that displayed the quality we required. Returning optics and arguing with opticians was not the most productive way to spend our days. You can literally thank Carl Zambuto for our smaller scopes becoming available again.
Our large mirrors (22" and over) are made by Kennedy Optics. Steve Kennedy is the only large mirror manufacturer who has NEVER had a mirror re-figured, by anybody, EVER.
Easily the most experienced telescopic optician in the United States today (over 10,000 optics and counting), Mr. Kennedy has dedicated his craft to producing only large telescope mirrors (this is a good match for us, since we only build large telescopes!). Mr. Kennedy works alone, no employees, no students, no one to blame when a bad optic "somehow" gets out. This alone is impressive, but what really sets him apart is how he figures his mirrors; The Star Test.
THE STAR TEST:
We have all seen or read about telescope mirrors that came with a bunch of paperwork and graphs, interferometer photos, a certificate of authenticity, and they still don't hold up under the Star Test. How can this be? The Star Test is the most critical optical test in the world for telescope mirrors. The Star Test can take a "good" mirror and show it for what it really is. Sure, Mr. Kennedy has a whole lab full of interferometers, masks, and testing equipment, but when it comes to putting that final, perfect figure on the mirror, that mirror is outside, night after night under the stars. No other large mirror maker offers this. When I've asked them why, they always say it would just take too long to correct each mirror, and that would slow down production too much.
THE OPTICAL PATH:
The other thing you get from the Webster Telescopes/Kennedy Optics team that you won't get anywhere else is (we saved the best for last):
YOU GET THE VERY SAME SECONDARY MIRROR THAT WAS USED TO FIGURE YOUR PRIMARY MIRROR!
That's right, the ENTIRE optical path is delivered to you just as it was during fabrication.
Think about this for a minute, and you will see how serious we are about optical quality.
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