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Criterion Dynamax 8 Schmidt Cassegrain Telescope

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In the interest of full disclosure, I have no financial stake in any of the companies mentioned in the following review.

"Is this guy serious?" I can already hear the snickers and heckling of all potential readers of this article. Despite Criterion’s revered status as a maker of 6” and 8” Newtonians, the infamous Dynamax SCTs are among the most reviled telescopes ever made. Eventually, every serious telescope junkie becomes curious about whether or not these telescopes could possibly be as bad as everyone says. I have heard stories of telescope collectors (hoarders? Hopelessly obsessed dweebs?) going out of their way to seek out these telescopes on the used market or auction sites just to be able to say they have one. This is, of course, a dubious distinction given the scope’s appalling stigma.

Some time ago I attended an astronomy open-house at a nearby college where there were numerous telescopes (modern and classic) that people could try out and look through. Among these telescopes was a Dynamax 8 in all of its ugly, gray bakelite glory.

Peering through the visual back without an eyepiece in place showed that the telescope was properly collimated. As for the star test (using a 10mm TeleVue Plossl), I have never seen such a perfect storm of optical aberrations. The star test revealed severe astigmatism, undercorrection, rough figure, pinched optics, and what may have been aberrations I’ve never even heard of before. What a mess! In focus (on a night of steady seeing after the scope had plenty of time to settle down to ambient temperature) Jupiter looked like an amoeba, and a deformed amoeba at that. The fork mount could easily be nicknamed “The Tuning Fork” because of the way it vibrated, and the clock drive had bizarre jumps at random intervals.

So, is the Dynamax 8 as terrible as its reputation? Boy howdy, is it ever! I’ve seen plastic toy store refractors with better optics than this beast. Anybody who actively seeks these out on the used market is a true masochist. Its no wonder that the Dynamax was ultimately the death rattle of Criterion. The optics, mount and drive are all a joke, and not a particularly funny joke either.


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