Where do the eyes cross?

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poogi
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Where do the eyes cross?

Post by poogi »

For people that shoot with both eyes open, are both eyes fixed on the target or the front sight?

I can't seem to focus on the front sight if my eyes are fixed on the target.
Rover
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Post by Rover »

OMG! Do a Search on this one before someone busts a blood vessel.
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rmca
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Post by rmca »

This is what rover meant, but with a nicer tone. (Sorry rover but this is his/hers first post...)

This topic has been debated to the exhaustion and then some... there are LOTS of information on this here, just do a basic search.

As always, your focus should be on the front sight, since that's where the pistol is pointing! If you focus the target you cannot know where the weck the thing is pointing to...

This applies to both eyes open, one closed, and even both closed :) You must see the front sight at all times...

Hope this helps
FredB
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not quite

Post by FredB »

There's more to this question than it seems to Rover and rmca. It doesn't do you a lot of good to see the front sight if you don't also see the relationship between the front sight and the rear (= alignment). If you focus both eyes on the front sight, only one eye will be able to see alignment, and you will also see two separate targets in the distance. Of course you can disregard what you see with your non-dominant eye, but then it isn't truly focused on the front sight. I suspect that people who shoot with both eyes open have the aim of their eyes (I don't know the correct term for this) converge at the target distance, even though their dominant eye is focused on the front sight. Dr. Wong has talked about prescribing shooting glasses with a long distance prescription in one lens and a close distance prescription in the other so the above could be done. For me, that sight picture is too confusing so I use an occluder. I suspect this is what the OP was asking about.

FredB
poogi
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Post by poogi »

I understand the the front sight is to be clear and in focus.

I was just wondering where the eyes converge (thanks FredB, that was the word I was looking for.)
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RandomShotz
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Post by RandomShotz »

I don't think the point of convergence is relevant to target shooting. Using right and left according to your diagram, information from the left eye is disregarded. Many shooters use an occluder to prevent the image from the left eye from becoming a distraction. I don't know if the left eye normally gravitates towards the front sight or down range but I suspect the latter.

When I've shot without an occluder at an indoor range, if the target in the lane to my right was reeled in, my attention was immediately drawn to the moving target. That was probably the result of hard-wiring in the visual system designed to attend to moving objects, but I think it means that while target shooting there are two independent images received by the brain and only one of them is getting attention at any given moment.

Roger
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rmca
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Post by rmca »

FredB

What I mean with see the front sight, is that it has to be in focus and centered in the rear sight, and both of them aligned under the fuzzy target, even with your eyes closed! :) It has to be burned in your brain (and everyone elses for that matter) by now!

poogi

Both your eyes work as a unit, you cannot focus on one thing with one and another with the other. What the non dominant eye can do is pull your focus to something else that moves or catches your attention. Hence the use of a blinder.

To answer your question I would say that both your eyes should be on the front sight, in order to achieve the following picture.

Hope this helps
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jliston48
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Post by jliston48 »

You CAN'T focus on the front sight with one eye and the target with the other!

Focus on the front sight with both eyes and let the relationship between the in-focus front sight, the slightly-out-of-focus rear sight and the grossly-out-of-focus target be established by the dominant eye.

As for being distracted by things on the range (eg the target next to you coming and going in air pistol), here's a thought:

Have you ever watched something intently and someone beside you says, "Wow, did you see that?" in reference to something that happened in your field of vision but you were concentrating so hard on what you were watching that you didn't see it?

Right! Well that's where you should be with your shooting. It takes a lot of work and practice but it can be done. So if the shooter next to you takes off his/her clothes during a match, you would not notice!!! (PS: Not a recommended training strategy - but you get the idea!)
jliston48
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Post by jliston48 »

Am I reading this right?

You can't focus on the front sight with one eye and the target with the other!

Focus on the front sight with both eyes and let the relationship between the in-focus front sight, the slightly-out-of-focus rear sight and the grossly-out-of-focus target be established by the dominant eye.

As for being distracted by things on the range (eg the target next to you coming and going in air pistol), here's a thought:

Have you ever watched something intently and someone beside you says, "Wow, did you see that?" in reference to something that happened in your field of vision but you were concentrating so hard on what you were watching that you didn't see it?

Right! Well that's where you should be with your shooting. It takes a lot of work and practice but it can be done. So if the shooter next to you takes off his/her clothes during a match, you would not notice!!! (PS: Not a recommended training strategy - but you get the idea!)
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RandomShotz
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Post by RandomShotz »

jliston48 wrote:Have you ever watched something intently and someone beside you says, "Wow, did you see that?" in reference to something that happened in your field of vision but you were concentrating so hard on what you were watching that you didn't see it?

Right! Well that's where you should be with your shooting.
Exactly.

My points are these: first, it is not desirable to have both eyes focused on the front sight. The sighting eye will produce an image of the front and rear sights and the target, hopefully all nicely lined up. If the "off" eye is focused on the front sight, it will produce an image of the front sight at a slight angle, with the rear sight and target someplace else. The brain naturally resolves images like this by attending to the point of focus, i.e., the front sight, and fudging the rest of the image so that it is out of focus but not doubled. By "fudging" I mean that the visual system substitutes a reasonable, coherent image where visual information is absent or inconsistent. This "post processing" is the reason the blind spot at the fovea is not noticeable except under special conditions and also why we are not aware of the gross distortions produced by the lens projecting an image on a (more or less) spherical retina. And this substitution is why the information from only one eye can be processed if a shooter is going to have a consistent and accurate sight picture.

Second, the human visual system evolved in the context of many challenges but shooting a pistol was not one of them. Psychological attention is drawn to motion; I would guess that is because predators move and awareness of predators is useful for survival. However much attention is focused on the sight picture with the aiming eye, information is still coming in from the off eye but focused attention allows us to disregard that information. The fact that movement in the visual field of the "off" eye, especially movement towards the me, would pull my attention away from my aiming eye does not necessarily show a lack of attentiveness on my part but is likely a response to a hard wired reflex. Admittedly, this could be overcome with training but I think it is telling that most shooters wear an occluder over their "off" eye. It also shows that the information from my left eye is coming from my right side which suggests that my off eye is not focused on the front sight, nor on the target, but somewhere off to my right, i.e., I probably look cross-eyed when I shoot. Which relates to the OP's original question.

So, to the OP: use an occluder and don't worry about it.

Roger
FredB
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Post by FredB »

jliston48 wrote:You CAN'T focus on the front sight with one eye and the target with the other!
Well, I can't do it. But Dr. Wong, with glasses he prescribed for that purpose, says he can do it. It certainly seems theoretically possible to me. Both eyes converge at the target, the dominant eye looks through rear and front sights focused on the front, and the non-dominant eye looks directly at the target focused there. I'm not saying it's the best way, I'm just saying it is possible.

FredB

(Dr. Norman Wong is a San Francisco optometrist who is also an accomplished bullseye shooter, with a Master classification. He has written extensively on vision and target shooting, and has prescribed shooting glasses for many top U.S. conventional and international shooters.)
paw080
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Post by paw080 »

FredB wrote:
jliston48 wrote:You CAN'T focus on the front sight with one eye and the target with the other!
Well, I can't do it. But Dr. Wong, with glasses he prescribed for that purpose, says he can do it. It certainly seems theoretically possible to me. Both eyes converge at the target, the dominant eye looks through rear and front sights focused on the front, and the non-dominant eye looks directly at the target focused there. I'm not saying it's the best way, I'm just saying it is possible.

FredB

(Dr. Norman Wong is a San Francisco optometrist who is also an accomplished bullseye shooter, with a Master classification. He has written extensively on vision and target shooting, and has prescribed shooting glasses for many top U.S. conventional and international shooters.)
Hey Guys; It's no problem for Gekkos and Chameleons....

Tony
Rover
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Post by Rover »

I warned you!

BTW No falo portuguese.
jr
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Post by jr »

Rover wrote:I warned you!
I think it would be cool to use the right eye to look through the sights at the (slightly out-of-focus) target while the left eye would be trained to follow the pellet (or bullet) in its path toward the target, thus making it easier to "calling your shots". (left-handed shooter reverses)
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conradin
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Post by conradin »

I think interviewing Yusuf Dikeç can get some ideas. Notice in the ISSF page his handedness is right, but there is no entry on Master Eye. Tan Zongliang may not be a good candidate because he wears glasses, and his bio listed him as right both handedness and master eye.
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rmca
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Post by rmca »

Rover wrote:I warned you!

BTW No falo portuguese.
If I had a cent every time someone tells me that...

I'm an optimist, go figure....

And BTW, it's written like this: Não falo português. ;)

Cheers
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ShootingSight
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Post by ShootingSight »

I'm NOT an optometrist, but I'm an engineer who has studied optics, and a photographer, and a shooter. And I own a company that makes vision related things for shooters.

And my decided opinion is that you do NOT want to focus on the front sight. Based on my testing, you want to focus at the hyperfocal distance of the rear sight. This is the focal distance at which your eye's natural depth of field (or the depth of filed afforded by an aperture) is centralized between the rear sight and the target. What this means is that the rear sight and the target will be equally blurry, and the front sight, which is solidly inside your depth of field will be slightly clearer than either the rear sight or the target. However your actual focal point is not ON the front sight, but out beyond it.

You can find the hyperfocal math on google, and do the dioptric lens conversion, but the bottom line answer is that a pistol shooter wants +0.75 diopters added to any distance correction you wear.

This mild positive power will force your relaxed eye back from infinity and focus you at the hyperfocal point. At the same time the uncorrected eye will be equally relaxed, but focused out at infinity. I'll have to actually try it, but I'm almost sure that if you look at the target, your eyes will converge on the target, but the corrected shooting eye will get a clear view of the sights.

Art
Rover
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Post by Rover »

Hey RMCA,

I told you so!

BTW I really like that pork with clams!

Loved Lisbon! I really got a chuckle when our cab driver tried to run down a nun on our way up to the castle. She really moved quick for an old gal!
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rmca
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Post by rmca »

Hi Rover

Yes, yes... I should know better by now....

Cab drivers everywhere are a different breed, but somehow, those in Portugal are quite... let's say refined... ;)

That is just one of thousands of dishes that can blow you away, especially if you're not afraid to try something new... And don't even get me started on desserts!

If you find yourself in my neck of the woods again, drop me a line and we will have a proper beer.

By the way, you never got to answer the original question in this post... (sorry couldn't resist the provocation!)
jliston48
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Post by jliston48 »

ShootingSight wrote:...my decided opinion is that you do NOT want to focus on the front sight. Based on my testing, you want to focus at the hyperfocal distance of the rear sight. This is the focal distance at which your eye's natural depth of field (or the depth of filed afforded by an aperture) is centralized between the rear sight and the target. What this means is that the rear sight and the target will be equally blurry, and the front sight, which is solidly inside your depth of field will be slightly clearer than either the rear sight or the target. However your actual focal point is not ON the front sight, but out beyond it.
OK, Art,you've got my attention. Up till now, I've based all my learning on this matter (sighting) on the opinions of expert coaches and World and Olympic champions - and it also seems to work for me over many years. When I do see the front sight clearly (and with all other factors - trigger control, etc working correctly), it is a good shot.

It sounds like you have never actually done this but your theory sounds good so I'll follow along and might even try it - right up the time when it starts to get freaky!
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