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Blackouts? (2 Viewers)

Woen

Well-known member
Netherlands
Hi,

Question for this knowledgeable forum. If I look straight through my binoculars the image is perfect, but if I move my eyes a bit I get some black half moons and it makes me a bit nauseous. Also when scanning around this happens. Is this called blackout and is the a solution to stop this from happening?
 
Your eyes are just a little too close to your binos so that when you move your eyes they begin to move outside the beam of light coming out of your binos. If your eyes were too far away from your binos you would not be able to see the full field of view.
You do not say whether you wear spectacles but if you do then instead of having the eyecups in their lowest position, unscrew them upwards one position. If this is too much and you begin to lose field of view then you can position the eyecups between fully down and one position up by fitting rubber o-rings over the eyecups to keep them in this intermediate position.

If you do not wear spectacles make sure the eyecups are unscrewed to the highest position. If they are already in this position then it would indicate that these binos with their eyecups and eye relief do not quite suit your facial structure (this means the position of your eyes within their sockets) and if the blackouts really interfere with your enjoyment of your binos you need to try out some different binos.
 

Your eyes are just a little too close to your binos so that when you move your eyes they begin to move outside the beam of light coming out of your binos. If your eyes were too far away from your binos you would not be able to see the full field of view.
You do not say whether you wear spectacles but if you do then instead of having the eyecups in their lowest position, unscrew them upwards one position. If this is too much and you begin to lose field of view then you can position the eyecups between fully down and one position up by fitting rubber o-rings over the eyecups to keep them in this intermediate position.

If you do not wear spectacles make sure the eyecups are unscrewed to the highest position. If they are already in this position then it would indicate that these binos with their eyecups and eye relief do not quite suit your facial structure (this means the position of your eyes within their sockets) and if the blackouts really interfere with your enjoyment of your binos you need to try out some different binos.
Thank you for your answer. Wearing spectacles so I'm going to try all of that out. Could you explain the rubber O rings trick a bit better?
 
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Thank you for your answer. Wearing spectacles so I'm going to try all of that out. Could you explain the rubber O rings trick a bit better?
I wear spectacles too and on one of my binoculars I needed the eyecups up a little from fully down, but not as far as the first built-in'click-stop' on the eyecup. So I removed the eyecups from the bino (a Zeiss SF 8x32) and pushed a rubber o-ring that was a fairly tight fit up each eyecup from the bottom end and then put the eyecups back on the bino and unscrewed the top part of the eyecups to the position I wanted which was about halfway between fully down and one position upwards. I then moved the rubber o-rings upwards a little so that they resisted any change to the eyecups' position, i.e. so they applied friction which resisted the 'telescoping' of the eyecups into a different position. This sounds more complicated than it was and if you were to put some fairly tight o-rings over the 'telescoping' section of your eyecups you would easily see where the best place is to stop them moving out of position.
OK?
 
I wear spectacles too and on one of my binoculars I needed the eyecups up a little from fully down, but not as far as the first built-in'click-stop' on the eyecup. So I removed the eyecups from the bino (a Zeiss SF 8x32) and pushed a rubber o-ring that was a fairly tight fit up each eyecup from the bottom end and then put the eyecups back on the bino and unscrewed the top part of the eyecups to the position I wanted which was about halfway between fully down and one position upwards. I then moved the rubber o-rings upwards a little so that they resisted any change to the eyecups' position, i.e. so they applied friction which resisted the 'telescoping' of the eyecups into a different position. This sounds more complicated than it was and if you were to put some fairly tight o-rings over the 'telescoping' section of your eyecups you would easily see where the best place is to stop them moving out of position.
OK?
I will give it a go! Strange thing is I did not notice this effect while testing and comparing binoculars, but now it starts to annoy me that I really have to be carefull how to place the binocular on my glasses. And 1 stop out is just a bit to much. I'm also going to try out different spectacles.
 
Also try playing with the IPD slightly - it's easy to have it just marginally off, and always move your head and binoculars as one unit particularly if the exit pupil is small, rather than moving your eyes.
 
Woen; One question and one suggestion. What is the binocular you are using? You might want to plant the bino firmly in one position as the slight movement of the bino in relation to the eyes can disrupt the optics. If you pan the binoculars make the head take the same change. Sometimes it helps to close the hands up on the rear of the binos as the contact of the hands on the sides of the face and the bino having less ability to move about. "BE" the bino! Regards, Pat
 
Woen; One question and one suggestion. What is the binocular you are using? You might want to plant the bino firmly in one position as the slight movement of the bino in relation to the eyes can disrupt the optics. If you pan the binoculars make the head take the same change. Sometimes it helps to close the hands up on the rear of the binos as the contact of the hands on the sides of the face and the bino having less ability to move about. "BE" the bino! Regards, Pat
Leica Noctivid 8*42. It kinda bothers me that for some reason I have to be so precise using it. Really have to find a solution for this problem :)
 
Leica Noctivid 8*42. It kinda bothers me that for some reason I have to be so precise using it. Really have to find a solution for this problem :)
On Ultravids, once you twist the eyecups all the way up, they remove by pulling straight out, with a fair amount of travel and friction which may enable you to create a slightly deeper and stable position (just 1-2mm can make the difference) without risking their falling out. Presumably Noctivids are similar?
 
Leica Noctivid 8*42. It kinda bothers me that for some reason I have to be so precise using it. Really have to find a solution for this problem :)
This is one of the downsides of some modern uber-expensive wider field binos. The degree of blackouts doesn't show up in the specs they use to sell the binos. Other aspects of design are pushed forward (e.g. wide field), sometimes at the expense of easy eye placement.

Sometimes you get stuck with an optimal position in between 2 of the click-stops. On my Zeiss SF 8x42, I have to extend the eyecups all the way out and then further unscrew them a turn to get it right, the binos work 10 times better this way.
 
The intermediate positions between the major click stops are absolutely vital for getting eye distance absolutely perfect. Eyecups not firm enough to resist being pressed against my glasses at reasonable pressure (which can increase when observing moments of high excitement!) are a real PITA. Fortunately most of my binoculars can be used with the twist eyecups all the way down, or are firm enough that the eyecups stay where they are. But if yours don't, the use of O-rings to space your eyecups at the precise distance (recommended by many here) is an excellent solution.
 
Hi,

Question for this knowledgeable forum. If I look straight through my binoculars the image is perfect, but if I move my eyes a bit I get some black half moons and it makes me a bit nauseous. Also when scanning around this happens. Is this called blackout and is the a solution to stop this from happening?
 

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It kinda bothers me that for some reason I have to be so precise using it.
Me too. If I use only one model for an extended period, it sort of locks into place and the problem disappears (for the most part). But I like to switch things up, so the learning curve starts all over.
 
Leica Noctivid 8*42. It kinda bothers me that for some reason I have to be so precise using it. Really have to find a solution for this problem :)
I'm curious to hear about a solution to this problem. I spent an afternoon with the NV 8x42 and it was very difficult for me to get a view without blackouts. I returned them the next day (there were also other reasons for returning them). No hassle with the Ultravids. Funny how their top of the line binoculars are so difficult to use for some. I could live with the position of the focusser but not with the blackouts. Maybe this thread will produce a solution.
 

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