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Hi JohnH
I would want to wait a while and see what the user concensus on the Meade's supposedly RC OTAs is first, but since I'm not planning on a spend for 6 to 12 months, that's not a prob.
Is that $8.5K for the OTA or OTA + alt az goto mount?
I've seen a couple of test comparisons of optical performance of the Meade RC vs RCOS RCs, and they were not impressive, but at a third the price what do you expect: pretty meaningless comparison really. What I have yet to see is a comparison between Meade RC and any of the mass market SCT OTAs (esp Meade and Celestron). This would be a very important comparison.
However, pure RC optics doesn't need a correction element, and the Meades use one. Makes me wonder why, is their mirror geometry dodgy, are they not truly primary secondary hyperboloidal, or is their astigmatism so bad that a normal corrector can't fix it?
As my imperfect understanding sees it, for the huge price jump from SCT to RC optical config, you go from SCT potential minimal chromatic ab from the front plate (much smaller than Mak Cas and usually unoticeable) and very minor comma at field edge, to astigmatism at field edge and no potential for chromatic due to no front glass with RC (and advantage the Meade's RC gives away for reasons they don't adequately explain). I'm not convinced it's worth it from the perspective of CCD imaging (big science instruments went to RC because of benefits of position measurement at high accuracy allowing for astigmatism, over dealing with comma). Always more to learn though, might change my views yet.
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