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Binoculers do not appear to be focussing properly.

First of all, Thank You,
Lenses do not seem to focus together properly.
Visualy the two lenses (right and left) do not completely come in sinc, or focus as ONE single view. This is NOT a complete ''double vision'' however it's not a good single objective display. It's more like a feeling of an ''Optical Vertigo'' (sea-sickness) view as your eyes attempt to naturaly focus, or ''train in'' on a single object.
When viewing through each side (right and left) seperately (blocking one eyepiece at a time), they seem to focus fairly well,
Spreading the pair or lessening the width across the eyepieces does not help or, for that matter, make any worse.
These are used on a boat, as if that's not difficult enough to steady and fucus, but the problem still exists on land and ''fixed'' with no movement what so ever.
Thanks again.
Any ideas or insight ? (No pun intended)
David

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Binox have a prism in each barrel to invert the image. When dropped or banged around the prisms may move in their mounts creating the problem you present. I have opened binox and reset the prism effecting a correction, but IF you unit is nitrogen filled you will be losing that anti-fogging benefit. If you choose to open your pair, check for movement in each prism, neither should be loose. Once you find the original proper placement, a drop of crazy glue does wonders - just a drop on one edge.

Posted on Jul 15, 2009

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