Orion Mirror diagonal

This Orion diagonal (model 8778) looks like the same one that Televue sells for a higher price.
Does somebody knows if the optical performance is the same for both ?

The TV model has a captive thumbscrew, maybe even a compression ring these days (not sure). However, they probably both come from Vixen, or at least they both used to. Here is where Tele Vue's extra QC helps. I once bought one from Orion and much later noticed it had several sleeks on the coatings. They also sometimes need a minor collimation adjustment, and they aren't really adjustable. So if you can imagine Tele Vue tossing out more of the bad ones first, you can see how your probability of getting a good one goes up. Orion's return policy is excellent, though. If you go that way, just make sure you _thoroughly_ check it out when you get it.

I hate to say this because they are more expensive, but I much prefer the ones that have casing machined out of aluminum rather than casted since they probably come collimated. I'm not sure if the reborn Lumicon is still producing it, but the Lumicon 1.25" used to be a good one, as is the Tele Vue everbrite model.
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Mike