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The tube assembly is shockingly bad on several scores.
(a) the last photo shows the corrector plate is held by three clips and the front of the tube is open, there is nothing to stop stray light entering between the corrector and the tube, reaching the primary and then the focal plane. The clip visible in the photo is intruding into the light path through the corrector, so expect to see spikes. Secondly it looks a pretty fragile mounting, either likely to misalign during transport or possibly break the corrector if it suffers a high point loading due to a minor bump in transit.
(b) the inside of the tube appears to be highly reflective metal. No thanks.
(c) leaving the hexagonal tube open might help the cool down but its going to collect dust and insects, and the optics are going to get dewy and dirty meaning the coatings won't last long. The sealed tube construction of Meades, Celestrons and Maksutovs is a huge advantage in terms of coating life.
(d) metal tube = expansion problems. Focus will not be stable, thermally.
(e) it is a very very ugly assembly. I wouldn't pay for that.
(f) the corrector looks uncoated.
If he's so mean he can't afford to build a decent cylindrical tube it leaves me wondering what else he has skimped on and how much of it is really true. For example I came across a commercially made scope some years ago which claimed to be a "schmidt cassegrain" but the "corrector" was just plate glass without the schmidt profile to it. Quite a few people shelled out good money for those scopes and were conned.
It's also possible its just a temporary prototype or lashup for testing, and a more appropriate commercial assembly follows later. If thats the case he's doing himself a disservice by showing such rubbish prematurely, far better to show the finished product.
His first name suggests he's really a russki, culturally. Beware.
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