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Possible problem with my new WO BV's..?

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#1 mike73


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Posted 03 January 2014 - 12:50 PM

I've just taken delivery of a new pair of WO binoviewers and this is my first taste of using two eyes instead of one and I've been pretty excited about getting them.
As usual any new astro related gear is greeted with complete cloud cover so I've just been playing about with the BV's and noticed something a little odd.

If I look through them at my computer screen with a blank white page it kinda looks ok until I close one eye at a time, the right side looks bright white which is what to be expected but looking through the left side its quite a bit dimmer than the right and also shows a very slight magenta cast!?
I swapped the supplied EP's over and still the same. My right eye is my strongest so I tried using that eye on the left side of the BV's and I still got the same dim magenta view.
Surely you should get the same view from each EP? Whys one side brighter than the other?

I also see a double view, like seeing both field stops.

Have I got a faulty set of binoviewers or do you think I should stop looking through them at a blank computer screen and shut up?? :grin:

#2 hoes


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Posted 03 January 2014 - 01:11 PM

I'm a total newbie with binoviewers - but I had a very similar thing happen when I tried out my first pair a few weeks ago. I had thought I had the distance between the eyepieces set correctly - but had not - fiddling with the eyepiece separation solved the problem for me.

#3 Tak North

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Posted 03 January 2014 - 03:01 PM

Yes, my binos do this as well. The BV Prisms actually polarize the light, and since they are at different angles to each other the light from any polarized light source such as your computer monitor will change quite noticeably in each side. You should notice less of an effect by looking at a non-polarized source such as a blank, white wall.

As for the alignment issue, you simply have to put it on a telescope to see the correct image. What you're looking at now doesn't really tell you anything.

#4 Eddgie


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Posted 03 January 2014 - 03:48 PM

There is often some imbalance in the beam splitter on the less expensive units.

The total light reaching your eyes is the same though and you still get the benefits of binocular vision.

IDP and rotation will fix the other issues.

Premium BVs usually have well balanced brightness.

Make sure your eyepieces are not tilted in the holders. I hold the tops down when tightening the holders.

#5 mike73


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Posted 03 January 2014 - 03:49 PM

Ahh thats great news, I was hoping there was going to be a simple explanation.

Thanks again

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