Hi,
I have a Stellarvue binoviewer and it's great. But they were a bit tricky to set up and get used to at first. I find there is a bit of a knack to observing thru them - but it's well worth the effort for the views you get. The moon and planets are spectacular. Having said that - the amount of light reaching each eye is definitely half of what you'd get through a regular ep, and the overall image is dimmer for that reason.
Cheers
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