Eye Dominance, Sighting and the Cue

[Particle Physics]

* Update.

I remember having balanced vision in my youth, potting balls at 89 degrees and the like, with cue centre chin. This means that my vision has changed; not unusual. Following an accident a few years back when my left eye was out of commission for a week, I wonder if my brain decided to go dominant eye. I've tried cue under left eye as Vmax suggested, and I can pot balls there too, but not quite as well as R eye; this could be down to head position though. I believe that either way, my brain has decided to go for one eye as it's main visual input.

I started patching my dominant eye yesterday, and will let folk know how I get on. It appears to work after an hour, i.e. balanced vision returns. Not sure how long it will last, time will tell I guess. I have a league match to play this Thursday and I'm not sure what vision to use. I guess I'll just have to 'see' at practice prior to the match and make a decision about whether to go domainant eye, or centre chin (following three days of patching, 2 hours at a time). As I've said before, there are big advantages in using centre chin if vision is balanced. I'll have to see if patching can achieve this goal. If not, it will have to be dominant eye cueing I guess?

[Particle Physics]

It is easy to change the sighting without changing the setup, use nic barrows correct head positon video on here, nic suggests this , which in effect is just about getting the line which looks straight to your brain(dominant eye information), therefore u could well b able to cue fairly straight, but if u are cuing across a line of aim(paralex error) u still wont make pots consistently. I think this manifests itself in players steering shots because subconciously on wrong line of aim.

Spot on comment.

[Manu147]

It is easy to change the sighting without changing the setup, use nic barrows correct head positon video on here, nic suggests this , which in effect is just about getting the line which looks straight to your brain(dominant eye information), therefore u could well b able to cue fairly straight, but if u are cuing across a line of aim(paralex error) u still wont make pots consistently. I think this manifests itself in players steering shots because subconciously on wrong line of aim.

[Terry Davidson]

Finally, I can agree with most of this string, especially the last post from manu147. The dominant or preferred eye is used all the time by the brain to select its preferred image so every player when standing behind the shot and doing his aiming will automatically be using whichever eye is dominant (if he has one) to guide the aiming and sightling process.

Once the line of aim is selected then the player must ensure he drops the head STRAIGHT DOWN on that selected line of aim and once he assumes the address position he should automatically be on the correct line of aim. If the player decides he is better off with the dominant eye over the cue then he had better develop a set-up where he brings the head down on a straight line with the dominant eye coming over the cue.

However, since the point of the chin (or the cleft in the middle) provides the player with a precise reference point it is very simple to bring the CENTRE of the chin down onto the cue (the nose can also be a good reference as it's right above the centre of the chin of course and easier to see in the peripheral vision too) and this will contribute to consistency in a big way. If a player decides to go with the consistent method outlined here but still wants his cue more underneath his dominant eye then the correct solution to my mind would be to turn the head slightly right or left when assuming the address position. This is what I have to do with my dodgy right eye and I believe (OK, except Jamie Jones, Joe Davis, John Virgo and probably a few others) most players will be much more consistent and accurate using this method of turning the head rather than moving the cue directly to one side of the chin or the other and thus changing the body alignment from what it was.

I will however strongly disagree with one statement made by PP and that is to adjust the head or cue when down in the address position. This would not be acceptable to any coach or any good player since you will always get the best perspective of the aiming line of a pot when standing up and over/behind the shot where you can easily see the three important aspects of it, i.e. - CB, OB and pocket and also easily detect the two lines of travel of CB and OB. If you move the head even 1mm sideways there is a good chance you will lose that correct line of aim.

One other point to mention...except with a dead-in pot the line of sight of the eyes (looking at the object ball) and the line of aim of the cue are ALWAYS different. Now for those who are now jumping up and down and saying IT AIN'T SO think about where the cue is aimed on any pot which is less than 1/2-ball. It will be aimed OUTSIDE THE EDGE of the object ball however the eyes are still concentrating on either BOB on the object ball or the centre of an imaginary cueball (or whatever aiming method a player chooses to use).

Since the eyes and the cue line of aim almost never line up and there's ALWAYS an off-set I don't think it's necessary to have the cue underneath the dominant eye unless the player feels he gets a better look for the line of aim for the eyes, which is to the object ball but not matched to the line of aim of the cue so why would a player change his set-up to develop this alignment. Changing one's set-up after a player has learned to pot is a very dangerous undertaking and not to be considered lightly.

Terry


Terry

[Particle Physics]

This is what i believe pp, but for some advice dont move the cue under the eye, but place the eye or tiit the head over the cue slightly to find the optimum position for you, you will already have picked your sighting line from standing up(with the dominant eye sending the information to the brain or vice-versa), so the line remains the same, easy to adjust, stance, setup remains pretty much the same.

Good call Manu. This saves having to find that special place R of chin for the cue. Just tried it on the pool table, and it is so much easier than placing the cue in exactly the right position. Optical principles and perception are the same of course, before anyone starts criticising! And yes, the cue is now more to the left, less towards the shoulder, which means I've adjusted my body less to get the cue into a specific position, the eye is in control and the body adjusts for the eye, not the body adjusting for the cue position. Thanks mate.

Here's another tip I've found useful for beginners of this method. As you go down or are down, close the undominant eye. The cue should appear perfectly straight to the dominant eye. If it doesn't, adjust it. Your eye line will match the cue line, and if you've selected the right angle; the true shot/geometric line.

[Manu147]

Sorry guys, I've been busy painting for the last couple of days, and potting balls! First off, it's great to hear so much forthright debate, that's what a forum is for.

Now here's the truth. 70% of people are dominant in one eye. This is a medical fact. It means that the information from one eye is being preferred by the brain for coordination. Dominant eye folk can even out the dominance using a couple of methods that I've outlined above or can go the patching route as has been raised; this changes the way the brain uses information from both eyes. Those who don't change face a problem. Firstly, they get down and line the shot up with the dominant eye, say the R, with the chin under the cue. The cueline and the eyeline are different, separated by a few degrees or more. You are putting the cue in the wrong place! On long pots, acute pots and heavy shots, this will lead to misses. It is essential that the eye line and cue line are lined up together, preferably over the true shot line (the geometrical line). These are the three important lines in all cue sports. It's not a problem for even sighted people because the chin divides the eyes, so all is balanced. The brain uses info from the left eye (left of the cue line) and the R eye (R of the cue line) in equal proportions. Essentially the two eye lines bracket the cue line in a parallel fashion.

Myth No.1 - You can force yourself into even sightedness using cue down centre chin? It's not generally possible unless you switch the undominant eye 'on'. Your brain, other things being equal will simply use the dominant eye and your body will consistently get the object of layering the eye line over the cue line over the shot line consistently wrong. Simply placing the cue down centre chin will not switch the undominant eye on.

Myth No.2 - Using the dominant eye means lack of depth of field. Not true. Cueing down the R side of the chin or the left side, still leaves one other eye for peripheral vision, giving depth of field, allbeit, across the ball more than if the cue was under the chin. Your undominant eye is still sending info to the brain, it's just that the brain uses the dominant eye to do the angles, sighting and cue line. It would anyway, but at least the cue line and shot line matched up now.

I've asked an ophthalmic optician about all this, so you can be rest assured it's true. Lucky for me, she's a mean pool player to boot, and understands the whole aiming process. Her father is a snooker player. I guess god wanted me to ask her these questions!

Solutions: some folk alter their set-up (stance, bridge, etc, etc) to adapt to dominant eye, whilst still putting the cue under centre chin, the cue is now across their line of sight from the dominant eye. It kinda works but is inferior IME to putting the cue under the dominant eye. But if it works for them, grand. However, if cue under the dominant eye did not work really well, pros like Trump, Robertson, Mark Allen, etc would not use the method. There is no way Judd could pot those balls if he was even sighted with the cue under his R eye! He does it for a reason; it works because he's R eye dominant. If it works, then they must have a dominant eye. If they didn't these players wouldn't be able to pot to this standard, because there eye line and cue/shot line wouldn't match up.

Now all it takes is a couple of sessions to see if this works. That's all the time it took me and I'm not a pro. Yes, it will take me a while to adjust my game to this new sighting, because moving the cue an inch, means the cue has moved, and so the set-up is slightly different. One side benefit I've noticed is that the cue has moved an inch to the R, and is now more under the shoulder than before, which all coaches advocate (and no, putting the cue under shoulder with the cue under centre chin did not work!). It will take a month or two to play in, but if I can jump to half centuries because of this, so can everyone else it might benefit. If nothing else, it's worth a go. One spends a lot of time playing snooker. If in all that time, one is making a fundamental error, how much time and frustration could one save, not forgetting a massive increase in enjoyment and playing standard, for the sake of a couple of sessions? If it doesn't work, no problem, at least you know now. Put it another way, folk on here have already spent more time in this post, than it would to run the test. They spend far more time buying more cues, tips, ferrules, cases, everything to do with snooker.

I await PJ Nolan's reply for some more info. But I wouldn't be surprised if he tells me much or all of what I've already said here.

This is what i believe pp, but for some advice dont move the cue under the eye, but place the eye or tiit the head over the cue slightly to find the optimum position for you, you will already have picked your sighting line from standing up(with the dominant eye sending the information to the brain or vice-versa), so the line remains the same, easy to adjust, stance, setup remains pretty much the same.

[Particle Physics]

Sorry guys, I've been busy painting for the last couple of days, and potting balls! First off, it's great to hear so much forthright debate, that's what a forum is for.

Now here's the truth. 70% of people are dominant in one eye. This is a medical fact. It means that the information from one eye is being preferred by the brain for coordination. Dominant eye folk can even out the dominance using a couple of methods that I've outlined above or can go the patching route as has been raised; this changes the way the brain uses information from both eyes. Those who don't change face a problem. Firstly, they get down and line the shot up with the dominant eye, say the R, with the chin under the cue. The cueline and the eyeline are different, separated by a few degrees or more. You are putting the cue in the wrong place! On long pots, acute pots and heavy shots, this will lead to misses. It is essential that the eye line and cue line are lined up together, preferably over the true shot line (the geometrical line). These are the three important lines in all cue sports. It's not a problem for even sighted people because the chin divides the eyes, so all is balanced. The brain uses info from the left eye (left of the cue line) and the R eye (R of the cue line) in equal proportions. Essentially the two eye lines bracket the cue line in a parallel fashion.

Myth No.1 - You can force yourself into even sightedness using cue down centre chin? It's not generally possible unless you switch the undominant eye 'on'. Your brain, other things being equal will simply use the dominant eye and your body will consistently get the object of layering the eye line over the cue line over the shot line consistently wrong. Simply placing the cue down centre chin will not switch the undominant eye on.

Myth No.2 - Using the dominant eye means lack of depth of field. Not true. Cueing down the R side of the chin or the left side, still leaves one other eye for peripheral vision, giving depth of field, allbeit, across the ball more than if the cue was under the chin. Your undominant eye is still sending info to the brain, it's just that the brain uses the dominant eye to do the angles, sighting and cue line. It would anyway, but at least the cue line and shot line matched up now.

I've asked an ophthalmic optician about all this, so you can be rest assured it's true. Lucky for me, she's a mean pool player to boot, and understands the whole aiming process. Her father is a snooker player. I guess god wanted me to ask her these questions!

Solutions: some folk alter their set-up (stance, bridge, etc, etc) to adapt to dominant eye, whilst still putting the cue under centre chin, the cue is now across their line of sight from the dominant eye. It kinda works but is inferior IME to putting the cue under the dominant eye. But if it works for them, grand. However, if cue under the dominant eye did not work really well, pros like Trump, Robertson, Mark Allen, etc would not use the method. There is no way Judd could pot those balls if he was even sighted with the cue under his R eye! He does it for a reason; it works because he's R eye dominant. If it works, then they must have a dominant eye. If they didn't these players wouldn't be able to pot to this standard, because there eye line and cue/shot line wouldn't match up.

Now all it takes is a couple of sessions to see if this works. That's all the time it took me and I'm not a pro. Yes, it will take me a while to adjust my game to this new sighting, because moving the cue an inch, means the cue has moved, and so the set-up is slightly different. One side benefit I've noticed is that the cue has moved an inch to the R, and is now more under the shoulder than before, which all coaches advocate (and no, putting the cue under shoulder with the cue under centre chin did not work!). It will take a month or two to play in, but if I can jump to half centuries because of this, so can everyone else it might benefit. If nothing else, it's worth a go. One spends a lot of time playing snooker. If in all that time, one is making a fundamental error, how much time and frustration could one save, not forgetting a massive increase in enjoyment and playing standard, for the sake of a couple of sessions? If it doesn't work, no problem, at least you know now. Put it another way, folk on here have already spent more time in this post, than it would to run the test. They spend far more time buying more cues, tips, ferrules, cases, everything to do with snooker.

I await PJ Nolan's reply for some more info. But I wouldn't be surprised if he tells me much or all of what I've already said here.

[Terry Davidson]

DandyA:

I agree that a player should ingrain a set-up in which he 'sees' the correct alignment of the shot. In my case, and in a lot of cases I think that might not be under the preferred eye but rather the point where a player gets the best binocular vision.

In this debate I can't use myself as an example because of my dodgy right eye, however I do have my head turned slightly right which brings the cue a little under my left eye but that is more for comfort than anything else.

I believe whatever position or head turn a player uses the brain will adapt to that given sufficient time and there is no need to mess with a player's sighting technique just to get the cue more under his preferred eye.

Terry

[Giggity1984]

[QUOTE=DandyA;658184]there is something I really don't understand about quite a few of the contributions to this thread ... I understand the brain can adapt but why not give it the best starting point ...[QUOTE=DandyA;658184]

As I said in my post above, it doesn't matter where you place your head. The reason for the dominant eye is to give us the ability to have depth perception.

If you lose your sight in one eye, it means you now see in two dimensions rather then three. It's not the case that one eye is more important then the other for viewing straight lines, otherwise people would close their non dominant eye and place their cue under the open eye.

The common "test" is to point at a spot and close one eye then the other and whichever eye open results in you still pointing at the spot is the eye to cue under. I think this is fine if your young as you have years to get used to it and it will become ingrained. However, I don''t think it's either necessary or important to do. the reason for saying this is, if you consider our "test", then when closing one eye and then the other, your still pointing at the exact same spot, ie it's still the same straight line!

So, with a straight object(a cue!!) in the standing up position and lowering ourselves down to chin on the cue, so long as the cue is pointed in the right place, what possible difference could it make where your head is placed?!

Bottom line: Find a position you think is right, for whatever reason you think it's right and stick with it! But it's not a magic bullet, nor do I think it's the reason you've started to pot balls(I 100% agree with Terry on this, it's probably accidentally aligned something else in your cue action.)

edit = I think it's also worth mentioning that you can change which eye is the dominant eye by wearing an eye patch for a prolonged period of time as this forces the brain to compensate. This is important in this discussion as it proves that it is an interpretation of a signal to the brain rather then one eye being "better" then the other.

As you can probably tell, I was forced to research this topic in the past. lol.

[alabadi]

happy birthday alabadi ... watch out for the crocodiles!

cheers mate, i will....lol

[DandyA]

there is something I really don't understand about quite a few of the contributions to this thread ... I understand the brain can adapt but why not give it the best starting point ...

I found the little test I did was quite amazing to me ... having setup everything dead straight, moving my head just a millimetre or two left or right made me think it was way off straight ... there was only one position which made the shot look dead straight ...

surely that is what I should use? I'm struggling to possibly understand any argument saying that I should use any different position and let my brain adapt or indeed any argument that says it doesn't matter where you place your head over the cue - of course it does ...

I do not claim any originality for the test I suggested, it's just a simple improvement of what many coaches suggest but try it ... it will give you confidence that you are sighting as best you can ...

obviously, it doesn't help with potting angles or straight cue delivery or positional play but as Meat Loaf might have said, if he was a snooker player, "one out of four ain't bad" ...

[edit] ... happy birthday alabadi ... watch out for the crocodiles!

[alabadi]

[QUOTE=Particle Physics;657928]

I think that the suggestion by DandyA is a good idea, and one that i will definatelly try, ill have to wait till i get home though, i'm on holiday in Egypt, havent found a snooker hall in Cairo yet, i'm really missing playing its been a week now, Happy hols mate, hope you're having a good one! Told you this would happen. lol.

Im determined to find a place here, however, Not tommorow its my birthday and i'm spending it cruising down the Nile...upeeee lucky me...lol

[Giggity1984]

I have to say, I think Terry has taken a pasting in this thread very unfairly. IMO he is correct. There is no other sport/(or ANY other scenario) that requires you to line up your dominant eye with your target goal/line. when your drawing a line on a bit of paper you don't hover your dominant eye over the ruler consciously, your brain and body just do it. When your firing a rifle you can use either eye to scope a target. The brain deciphers the information by itself. The reason we have a dominant eye is to enable us as human beings to have a level of depth perception. The bottom line is to pick a place to have your cue (for whatever reason you believe it needs to be there) whether it's 6 inches to the left or square in the middle of your chin and concentrate on other things.

[Terry Davidson]

manu: (PP, sorry for sort of hijacking your thread).

If you found a player who did NOT have the cue running under the dominant eye and was a weaker player like the 2 you mentioned above, how would you determine if the cause of their poorer potting was due to the cue not under the dominant eye or them not delivering the cue straight? It's a very tough thing to determine.

Then, how would you go about correcting the dominant eye aiming? By inference what you are saying is these 2 players are not aiming correctly or at least not getting the best visual image of the pot and could improve their potting by moving their cue more underneath the dominant eye. In other words changing their natural set-up, which could be very dangerous.

A quote from Nic Barrow on trying to change a player's sighting...'Be careful when attempting something this comprehensive with a player. Before taking on this task ask the player in the first instance if he wants to do it and secondly does he have a match coming up within the next month, especially a professional. It takes at least a month of daily practice to switch over to a different sighting technique, and that would be for a pro.'

If I was to take on changing a player's sighting set-up and technique I would be very careful to first determine if that player is sighting incorrectly or is he not delivering the cue straight. So, how would you determine the sighting half of this?

For me, I would have the player line up on the baulkline and aim to the edge of the leather on a top pocket and then standing behind the pocket determining if his cue is exactly on line. (One of those laser sighting devices that attach to the cue would be very handy but this can also be done with a video camera and software analysis or even by sight but that wouldn't be as accurate.

Then have him close his eyes alternately and ask him which eye shows the shot to be aligned perfectly. Then repeat the same exercise using a closer pocket, like from the baulkline to the edge of the leather on the green pocket as he may use a different eye for shorter shots (although that is very rare).

This exercise will determine two things, first if he is aiming correctly and second which is his preferred eye. You could explain to him that you have determined he is not lining up on the shot correctly and he needs to change his aiming technique by placing the cue more under the determined preferred eye but also explain there might be some necessary changes to his set-up that have to be made, for instance re-aligning the head, shoulder, elbow and grip hand and even perhaps the straight leg foot so everything can be kept on line.

Now set up a long blue and with the video camera over the edge of the leather have him pot the blue, leaving his cue extended at the end of the delivery. Determine if the cue is still on line to the edge of the leather, but more importantly play back the video using frame-by-frame and see how straight the cue was on the line of aim at the instant of striking the cueball. In a lot of cases, even with some very good players I've seen where the player is NOT striking the centre of the cueball so the first thing that has to happen before any changes are made is to get the player striking the centre of the cueball.

Then you can move on to correct his sighting, but as I said it's a very complicated process and in most cases most players will be able to select the proper line of aim however a different story when the drop down into the shot as you have to really check and see if they are on the correct line of aim. If they are then their sighting really doesn't need any re-alignment and if they are not then you really have to analyse everything about their set-up BEFORE you have them start moving the cue around or moving the head around. The safest way is to have them turn the head to align their preferred eye but that can only be done if it doesn't introduce discomfort.

In both the Master Coach training with Nic and the Senior Coach training with Terry/Wayne Griffiths sighting was barely touched upon and then only using the SightRite device. Because of my damned right eye I always see 3 lines with the SightRite with one being quite a bit darker than the other two, but turning my head did not eliminate the other 2 lines.

My theory is aligning the cue under the preferred eye is not at all important to correct sighting and doing this change will mean the player may have to re-indoctrinate himself with his new image of the potting angles. I believe the brain, as long as it's given a good binocular image to work with and the player stays consistent with his aiming technique, will determine the correct sighting line as long as the player has the chin centered or nearly so on the cue. I also believe turning the head slightly is the best way to achieve this rather than moving the cue to the left or right of the chin.

It's fine that you disagree...I doubt any two coaches agree 100% on everything as I don't agree with everything Nic Barrow has taught me even though he is my coach.

Terry

[Manu147]

On here there are players who have the cue running under the non-dominant eye. I have found students who also do this and if it's something that I feel is hampering their ability then I will try and get them either to centre chin or else turn the head to bring the preferred eye more into line with the cue, but that would only be for a student who has poor vision in one eye.

I still believe determining the correct line of aim is the easiest part of the technique for any player who has a little experience and the really difficult part is delivering the cue consistently straight. Compromising the player's binocular vision I don't see as a correct solution.

Living in Canada and in the country I don't have access to the number of good players that you have and I've never coached a professional player although I have coached some good players and as far as I can remember the preferred eye theory never came up at all and they just naturally cued wherever the cue was, be it centre chin or to one side. I also found a number of good players who have the head turned one way or another and there was no relation to the preferred eye.

However, you would be able to get a much better sample than I can but be sure to use the check to see which eye actually gives them their line of aim and compare that to which eye they believe is their dominant eye and you might find that the two do not always align up.

Terry

That was my point, in all cases it was the same with the exception of two players, who also are the weakest players in my club, so on that evidence i am in difference to ur ideas.