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Eye pain from viewing through binoculars? (1 Viewer)

Binastro

Well-known member
Astigmatism is mainly cured by glasses having a cylinder prescription at the correct angle.

I would think that your binocular has enough eye relief for use with glasses.

My guess is that headaches come from a combination of reasons.

If one looks at a bright star with one eye at a time then astigmatism shows the star as a line, not a point.

Regards,
B.
 

Binocollector

Well-known member
Germany
Any advice or resource for a way to reliably check the collimation at home? They are brand new but I guess it happens through shipping most likely?
There are a number of ways. You can look at a straight line, then slowly remove the bino until you got two seperate exit pupils but keep the straight line in view. Once the image separates in two -- you should be able to see, if there are alignment issues between the two barrels. You can also quickly close one eye than the other for a couple of times, while looking at a horizontal line. Sometimes that shows alignment issues as well.
 

akadius

Well-known member
United States
Had something vaguely similar with a pair of bins that were marginal on ipd for me, I was subconciously centering on my strongest eye so the other complained. In theory they should have been OK from the specifications.

My daughters astigmatism meant that she could cope with some of my binoculars but not others, even with prescription glasses on. With her it ended up with running through about 10 pairs to find one that she felt comfortable with. It seemed to be very eyepiece dependent with her choice being an older model against the current version that had 'improved' eyepieces.

At the end of the day poor collimation (even after being maintained) has been the most common problem I have encountered.
How did you sort out the issue with your weaker eye getting strained? I've started trying out my eyes at smaller and smaller text. My right eye, the one I have the strain/ pain in is clearer weaker. Last time I had my eyes checked I was just about 15/15, but I suspect there's been a bit of a deterioration in vision.
Glasses/contacts or lazer surgery are the normal treatments. Obviously try other binoculars, but if you get the same issues with multiple pairs it might be astigmatism. Often with a slight astigmatism it only causes eye strain when you've been staring a lot - it's common for heavy computer users for example.
I do need to try other binoculars and see how they feel. I'll need to give my eyes a rest. Now that you mention heavy computer users, I have been on the computer quite a lot over the last several days as well due to work. I had a project come in that I have had to spend a bit more time than usual on. I don't think the computer is what caused the eye strain but it could be helping to perpetuate it. I've noticed the eye strain definitely being more prominent at the end of and after a viewing session with the binoculars.
 

paddyluke

Well-known member
Wales
has any one else looked through the binoculars,surely if they are fine when someone else looks through them it can't be the binos, if another person see's the same problem then it has to be faulty binos:unsure:
 

akadius

Well-known member
United States
Astigmatism is mainly cured by glasses having a cylinder prescription at the correct angle.

I would think that your binocular has enough eye relief for use with glasses.

My guess is that headaches come from a combination of reasons.

If one looks at a bright star with one eye at a time then astigmatism shows the star as a line, not a point.

Regards,
B.

I have set up an eye appointment for tomorrow morning since it is one of the first and easiest things I can do. And now that I've noticed my right eye's vision is weaker than it used to be I think I need to do it regardless of the binocular stuff anyway. I will ask them about astigmatism and mention the strain and pain I'm having and report back here. Thankfully I have not been experiencing any headaches, just the pain in my right eye.

I'll have to try that with my astronomy binoculars when I make it out again.
 

akadius

Well-known member
United States
There are a number of ways. You can look at a straight line, then slowly remove the bino until you got two seperate exit pupils but keep the straight line in view. Once the image separates in two -- you should be able to see, if there are alignment issues between the two barrels. You can also quickly close one eye than the other for a couple of times, while looking at a horizontal line. Sometimes that shows alignment issues as well.
Thank you for riding that out. I am going to try that within the next day or two after I give my eyes a rest like suggested by another number on here. I have woken up today still with the pain lingering in my right eye so I think it is best to try to take it easy.

To make sure I understand you, when trying both of the ways you mentioned to check alignment the straight line is not consistent or straight between the two barrels then that's indicative of alignment issues, right? Thank you.
 

akadius

Well-known member
United States
I would suggest resting your eyes for at least a day from bright light or stress before doing any tests.
Thank you. I think that is great advice. I wouldn't want to push it too far. And this morning I had woken up with the strain and subtle Pain still present and lingering in my right eye. So I suppose I should take a rest, though I don't want to and would like to figure this out! I know it is for the best.
 

Binocollector

Well-known member
Germany
When looking at that straight line (depending on how close the bino can focus, I sometimes use the edge of the TV) and trying to keep the binos straight at the same time -- yes, then alignment issues should become obvious between left and right side, when "splitting the image" by slightly moving the bino away from the eyes. You should be able to see if one side is higher than the other or twisted in any direction.
 

akadius

Well-known member
United States
has any one else looked through the binoculars,surely if they are fine when someone else looks through them it can't be the binos, if another person see's the same problem then it has to be faulty binos:unsure:
Hey, that is a good idea. Thank you for posting that. I am going to attempt to get my girlfriend to spend some time looking through them today and see how it seems to her. She does not seem very interested in binoculars in general. So we will see if she will spend some time testing them out. If she does I'll report back!
 

paddyluke

Well-known member
Wales
Hey, that is a good idea. Thank you for posting that. I am going to attempt to get my girlfriend to spend some time looking through them today and see how it seems to her. She does not seem very interested in binoculars in general. So we will see if she will spend some time testing them out. If she does I'll report back!
i think you need someone who knows what to expect when it comes to looking through binoculars
 

akadius

Well-known member
United States
When looking at that straight line (depending on how close the bino can focus, I sometimes use the edge of the TV) and trying to keep the binos straight at the same time -- yes, then alignment issues should become obvious between left and right side, when "splitting the image" by slightly moving the bino away from the eyes. You should be able to see if one side is higher than the other or twisted in any direction.
Thank you so much. I didn't know it was so simple to check collimation/alignment issues. I'll post again as soon as I'm able to do this
 

akadius

Well-known member
United States
i think you need someone who knows what to expect when it comes to looking through binoculars
Sadly I don't have anyone nearby that's familiar enough with binoculars to help me out. I was thinking if she spent enough time with them and it's the binos, perhaps she works experience a similar strain after enough use.
 

Brink

Well-known member
I think the better quick alignment check is to focus your left eye on a fairly bright star through the binocular. Then de-focus the right eye as much as possible with the diopter adjustment. Then look through the binoculars with both eyes at the same time. If the focused star is near the middle of the defocused star you are in good shape. If the focused star is outside of the defocused star your alignment is not good. This method will probably better detect significant misalignment in the horizontal direction than the 'straight line' test.

This method, or variations of it, is pretty nifty too especially if you want to check multiple IPD settings: 5 - Nuevos artículos - Collimation of Binoculars with a Lamp, a Mirror and a Screen (recommended)

Exposure to too much light seems very unlikely. There are transmission losses through a binocular, so the amount of light reaching your retina is generally less through optics than unaided viewing (unless you are specifically looking at something very bright like the sun or a laser or a specular reflection of either).

I wouldn't discount the possibility that your eyes just don't agree with the optics of this binocular. Maybe you are getting the rolling ball effect? If you are really putting a pair of binoculars to the test and doing a lot of scanning and looking around within the FOV this could cause some eye fatigue. You can find a lot of posts on this site about people who have had trouble with specific binoculars (often binoculars with very wide and/or flat or flat-appearing fields). It could be that your eyes/brain are much more comfortable with a modest field with gentle curvature or pincushion distortion. Even the very 'best' optics can be disagreeable for some people and it is highly dependent on the individual user.

Constantly fiddling with the diopter might be a problem too. Bill Cook (WJC) posts on here about this all the time. You don't want your eye muscles and the diopter battling each other for best focus. Your eyes end up strained and you don't get a good diopter setting. Ideally your eyes will be relaxed (focused at infinity) for diopter setting.
 

akadius

Well-known member
United States
I think the better quick alignment check is to focus your left eye on a fairly bright star through the binocular. Then de-focus the right eye as much as possible with the diopter adjustment. Then look through the binoculars with both eyes at the same time. If the focused star is near the middle of the defocused star you are in good shape. If the focused star is outside of the defocused star your alignment is not good. This method will probably better detect significant misalignment in the horizontal direction than the 'straight line' test.

This method, or variations of it, is pretty nifty too especially if you want to check multiple IPD settings: 5 - Nuevos artículos - Collimation of Binoculars with a Lamp, a Mirror and a Screen (recommended)

Exposure to too much light seems very unlikely. There are transmission losses through a binocular, so the amount of light reaching your retina is generally less through optics than unaided viewing (unless you are specifically looking at something very bright like the sun or a laser or a specular reflection of either).

I wouldn't discount the possibility that your eyes just don't agree with the optics of this binocular. Maybe you are getting the rolling ball effect? If you are really putting a pair of binoculars to the test and doing a lot of scanning and looking around within the FOV this could cause some eye fatigue. You can find a lot of posts on this site about people who have had trouble with specific binoculars (often binoculars with very wide and/or flat or flat-appearing fields). It could be that your eyes/brain are much more comfortable with a modest field with gentle curvature or pincushion distortion. Even the very 'best' optics can be disagreeable for some people and it is highly dependent on the individual user.

Constantly fiddling with the diopter might be a problem too. Bill Cook (WJC) posts on here about this all the time. You don't want your eye muscles and the diopter battling each other for best focus. Your eyes end up strained and you don't get a good diopter setting. Ideally your eyes will be relaxed (focused at infinity) for diopter setting.
It's supposed to be clear out tonight so I might give the star alignment check a quick try so long as my eye is feeling up for it.

And I didn't know that some people eyes simply disagreed with wider FOV. I hope that's not the case, but I suppose it's possible. I wish I had more experience with more binoculars so I could better gage if that's the case.

Also, I have fiddled with the diopter during each viewing, sometimes more and others less trying to find the sweet spot. I was able to tell that my right eye was not able to see quite a much detail as the left even at what seemed to be the best it clearest diopter setting for my right eye. I also could feel my right eye didn't seem to like the image being out of focus while doing this, but that was a subtle feeling.

Thank you for your thoughts!
 

Brink

Well-known member
I don't want to imply that a wide FOV is necessarily a problem (I love a wide FOV) for the viewer. Optical imperfections like CA and coma tend to increase away from the center of the FOV. The need for field curvature or distortion would also increase as the field gets bigger. There are probably some wide binoculars that would be "better" if the field was stopped down a bit smaller. By most accounts the NL pure is an outstanding instrument because of how well they perform even across their exceptionally wide field (I haven't looked through one), so as with most things YMMV
 

akadius

Well-known member
United States
When looking at that straight line (depending on how close the bino can focus, I sometimes use the edge of the TV) and trying to keep the binos straight at the same time -- yes, then alignment issues should become obvious between left and right side, when "splitting the image" by slightly moving the bino away from the eyes. You should be able to see if one side is higher than the other or twisted in any direction.
It looks like the binoculars are aligned as I tried your method and the line appears straight when I pull the binoculars away from my eyes. So I'm thinking it's me.
 

akadius

Well-known member
United States
I think the better quick alignment check is to focus your left eye on a fairly bright star through the binocular. Then de-focus the right eye as much as possible with the diopter adjustment. Then look through the binoculars with both eyes at the same time. If the focused star is near the middle of the defocused star you are in good shape. If the focused star is outside of the defocused star your alignment is not good. This method will probably better detect significant misalignment in the horizontal direction than the 'straight line' test.

This method, or variations of it, is pretty nifty too especially if you want to check multiple IPD settings: 5 - Nuevos artículos - Collimation of Binoculars with a Lamp, a Mirror and a Screen (recommended)

Exposure to too much light seems very unlikely. There are transmission losses through a binocular, so the amount of light reaching your retina is generally less through optics than unaided viewing (unless you are specifically looking at something very bright like the sun or a laser or a specular reflection of either).

I wouldn't discount the possibility that your eyes just don't agree with the optics of this binocular. Maybe you are getting the rolling ball effect? If you are really putting a pair of binoculars to the test and doing a lot of scanning and looking around within the FOV this could cause some eye fatigue. You can find a lot of posts on this site about people who have had trouble with specific binoculars (often binoculars with very wide and/or flat or flat-appearing fields). It could be that your eyes/brain are much more comfortable with a modest field with gentle curvature or pincushion distortion. Even the very 'best' optics can be disagreeable for some people and it is highly dependent on the individual user.

Constantly fiddling with the diopter might be a problem too. Bill Cook (WJC) posts on here about this all the time. You don't want your eye muscles and the diopter battling each other for best focus. Your eyes end up strained and you don't get a good diopter setting. Ideally your eyes will be relaxed (focused at infinity) for diopter setting.
Hey, the sky is clear tonight so I outside for a moment to try your method of looking at a star. When I set the diopter all the way over as you suggested, I got an image of a clear star with a fuzzy one that was over the clear one. So it appears they are aligned properly. Thanks for that cool tip!
 

Bentley03

Well-known member
United Kingdom
Hey, the sky is clear tonight so I outside for a moment to try your method of looking at a star. When I set the diopter all the way over as you suggested, I got an image of a clear star with a fuzzy one that was over the clear one. So it appears they are aligned properly. Thanks for that cool tip!
That's terrific, you've checked and double checked alignment and you're satisfied collimation is true. Congratulations, you have a good example!

But, I guess that's good and bad news, the instrument was the easiest thing to rule out as being the cause of your eye pain/strain, so let's hope your optician can pinpoint the real cause for you.

Please keep us updated on what your eye test reveals. I, for one, would be very interested.

Good luck! 🙂
 

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