Hi - I just picked up at yard sale an older model Orion 8” f/3.9 (I believe) OTA. Optics look nice and clear, although I haven’t figured out how to really set it up yet, or learned to collimate it. After I got it home, I noticed that there is a visible seam running along the entire length of the tube pronounced enough that the tube kind of bulges out a tiny bit beyond the rings at both ends. The tube is clearly no longer perfectly round. The inside of the tube looks straight and true, but it still concerns me a bit. Is this typical? Is it detrimental to viewing? Or is it just aesthetics that I’m talking about? It is an old model, and this could be due to age. I bulge a bit myself after all these years.
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