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12" LightBridge optics upgrade?

Started by m87, 10/28/2009 09:28PM
Posted 10/28/2009 09:28PM Opening Post
I recently picked up 12" LightBridge to use during a dark skies trip out west. Had it shipped direct to the site, used it for a week, then left it with some astro-friends out there. I'm generally not a big fan of Meade products, but I have to say I was very impressed with the design and mechanics -- highly useable scope. Very solid OTA. Decent 2-speed focuser. I did have to shim the focuser 0.03" on one side to nail the collimation. And some Bob's Knobs and springs were a good upgrade. But considering the price and that it was "in stock" lots of places, I was very impressed.

Optics were pretty good, though I wanted better. Star testing with a 5mm Nagler showed the primary mirror had some astigmatism -- maybe quarter wave -- that rotated around with the mirror. Meade probably only guarantees "diffraction limited" which I feel it was -- Epsilon Lyra showed reasonable Airy disks.

This leads to my question: Has anyone had any luck upgrading the mirrors, or getting them refigured? It seemed to be a slightly odd size -- about 303mm diameter. The mirror cell design only has about 1mm of leeway on the mirror diameter, so a standard 12.5" drop-in replacement seems out of the question.