PDA

View Full Version : optical illusion?



heater451
06-07-2006, 05:12 PM
Okay, so I was knocking some balls around on the table, and found a shot that didn't make sense to me:

START(%Jd3J1%Pj4W1%Ue4K8%Vi9V4%WX8D4%Xc1I4%Y[2D4%Zc2I3%[_0D9%\c3I1)END

WEI table (http://endeavor.med.nyu.edu/~wei/pool/pooltable2.html)


Now, I make many shots by sending the "outside edge" (equator) of the cue ball to the contact point on the object ball, but for some reason it wasn't working on this shot. Even lining up the contact point with my cue, and choosing different parts of the pocket, from center-pocket, to outside point, I kept overcutting this shot (red arrow). With dead-center, soft-to-medium hits, I overcut the ball like 13 times in a row.

With a little bit of frustration, I hit the next one fuller and harder, and lo and behold, it went in. The next five in a row, I aimed the center of the cue ball directly at the contact point, and absolutely hammered the ball in, every time!

What's confusing me, is that, with how I was aiming and hitting (hard), I would have expected to undercut, "earlier than the pocket", into the rail (blue arrow), but not so.

Any ideas why I would get an overcut, considering that there was no sidespin or draw, and there shouldn't have been any squirt or side-throw (as opposed to forward-throw, which would have helped to pot the ball?

I would even say it was simple, bad aim and/or stroke, but I consistently cut it badly each time, with what I thought was the correct contact/aim point.

One thing: I did not line up the shot **exactly** the same each time, but roughly the same cut was necessary each time.

Also, if it matters, the cloth is "medium". Not fast, like Simonitz (sp?), but not shag carpet, like the IPT likes. More like what you should find on an 8-ft table, to make it play "average" speed, but this is a 9-ft table.

If anyone else actually tries this shot, please let me know if you have similar results.



===========================

Bob_Jewett
06-07-2006, 06:51 PM
<blockquote><font class="small">Quote heater451:</font><hr> ... Now, I make many shots by sending the "outside edge" (equator) of the cue ball to the contact point on the object ball, .... The next five in a row, I aimed the center of the cue ball directly at the contact point, and absolutely hammered the ball in, every time!
... <hr /></blockquote>
You aren't seeing the shot accurately. If you really send either the edge of the cue ball or the center of the cue ball towards the contact point, you have no chance at all to make the shot (except for very thin cuts and very full shots, respectively). Geometrically, your aiming system is completely broken. I conclude that you do not aim geometrically, and you do not really send the chosen part of the cue ball towards the contact point.

pooltchr
06-07-2006, 08:04 PM
I have to agree with Bob. The aiming method you are describing can only work on a very limited number of shots. The edge of the cue ball can only make contact on the edge of the object ball. And aiming the center of the cue ball to the contact point can only work on reletively straight in shots.
Steve

Jal
06-07-2006, 08:56 PM
The contact point on the object ball (point opposite the pocket) should always lie approximately halfway between the edges, as well as halfway between the centers of the balls. It's only approximate because of, mainly, throw. But halfway is pretty close.

So with regard to the edges, maybe you're seeing things more accurately. But it looks like you may have gone too far the other way; there's no way that sending the center of the cueball to the contact point on the object should work, except for a straight-in shot, or nearly straight with an assist from throw.

If the cueball was smaller than the object ball, that could explain, to some degree, the results you experienced. But you probably would have noticed the size difference if it threw the geometry off by that much.

I once missed the following shot 12 times in a dozen tries:

START(
%JU1Z8%P\5X9%WE5Z9%XS6Z8

)END

Thicker, thinner, nothing helped. I don't know what it was because I actually played better than average afterwards. Fortunately, that shot didn't come up. Maybe it's best to attribute these things to some weird twisting of space-time and leave it at that.

Jim

heater451
06-08-2006, 05:00 PM
Bob, I think you misunderstand what I mean, by "outside edge". I tried to qualify it with "equator", but it must not have been clear.

Consider this:

If you look from behind the cue ball, so that it is represented by a circle, then using the "outside edge" would mean aiming to hit with the left- or right-most point of the circle. Although, this would explain the overcutting, this is not what I am using.

If you use the "equator"--represented by a circle, when viewed from above, then the point that I am "aiming" with is where the "equal-distance" point on the cue ball would (roughly) be--like Jal brought up. Instead of a ball, if you imagine a disc, floating horizontally, at the level of the center of the cue ball, then you are seeing that I am dealing with the edge of the disc.

If it helps, consider the disc edge (which is still the "equator" of the cue ball) as having a 0-degree point at the right-most point. I am not trying to hit the object-contact point with the leftmost, 180-degree point, but something in the 135-degree (half-ball) to 175-degree area. [Don't make me break out radian references, /ccboard/images/graemlins/smile.gif] --for reference, the 275-degree point on the disc points back towards the shooter.

That's why I was confused, when I tried to contact the object ball with the correct cue ball contact point, I overcut. But, when I aimed using the center of the cue ball, and let the ball hit wherever the "natural" curve of the ball put it, I would pot the ball.

Anyway, I also tried using the "regular", ghostball/ 1-1/8" from the ball type of aiming, and had the same result.

I'm still thinking that I am missing something. . . .



======================

recoveryjones
06-08-2006, 07:21 PM
Bert Kinister talks about "optical illusions" in his two instructional videos called "the Secrets of long Hard Shots" and "The Secrets of Shot making"

He instructs the viewer to aim dead on at the shots Illustrated (wei Table)below that obviuosly need cutting to successfully make the pot.Basically he is not saying that you won't be cutting the ball, because cutting the ball is the only way to make the shot with no english. Of course we all know you can throw a ball in with english. He just is saying because of optical illusions to aim dead on. I tried it and the two shots illustrated below to my amazement go in time and time again (from both sides of the table)when aimed dead on.I'm not sure if ones subconcious mind makes the adjustment or if it's an optical illusion, all I know is that the ball goes in.

START(
%Id3Z2%PK5Z7

)END

START(
%Ij9H3%PG2R1

)END


WEI table
http://endeavor.med.nyu.edu/~wei/pool/pooltable2.html

Note the two shots illustrated above if a straight line were drawn through them should in fact miss the pocket by a few inches if hit dead on. I you do in fact hit them dead on(center ball, no english) they will miss the pocket by a few inches.

Aim dead on and watch them go in!Obviously you have cut them if you made them, however, aim dead on because of what bert(not me) calls an optical illusion.Move the ball an inch further away from the pocket and to your suprise it may also go in with a dead on aim.

Joe Tucker also talks (On his DVD) about optical illusions with on the rail jack up shots.Because your eyes are coming at the cue ball from an elevated posistion, what you see as a center ball hit may be an optical illusion. You may have to aim to cut the ball a fraction from this jacked uppped viewing position to actually get the dead on hit you desire.
Also when the cue ball and object ball are really close together a higher stance can be benficial as a low(chin on cue stick) stance can mess with your visual perception.

Many pool players miss certain shots by aiming time and time again at the same spot because of optical illusions.They continually miss the shot thinking that they've aimed improperly and blame in on a badly delivered stroke when in actuality they've hit the object ball exactly where they've aimed.

In conclusion I believe there are optical illusions with certain shots on the pool table.The thing to do I guess is to set up shots that you continally miss and aim them differently until you can continually make them.

I posted this info on AZ and some people thought I was a quack, however, I was just mearly trying to relay some interesting,yet controversial teachings of Bert Kinister. The only thing to do is set the shots up as illustrated and aim them dead on with no english.

If it works you have learned something new and can buy Bert DVD's ...LOL.
If it doesn't work what have you lost by trying???
RJ

heater451
06-09-2006, 04:08 PM
Interesting, RJ. . . .I did notice that I hit a shot similar to the second one that you posted, doing the same thing (aiming center-cue-ball to contact-point).

I didn't take the time to experiment, but I do recall a few years back, when I noticed that many long-table, thick-cut (fuller hit) shots seemed to go in, using that technique. In fact, I only thought it odd, because I simple **beleive** that since the balls are curved, aiming directly at the contact point yields the wrong hit. Evidently, other factors allow this to not be the case for some shots.

I'm beginning to think that cuts up to 30 degrees or so can probably be hit this way, to pot the ball. Of course, a longer object ball-to-pocket distance probably decreases the "surety". Then again, the first shot you diagrammed seems to be plenty far from the hole. . . .

Now that I'm thinking about it, it seems like another optical illusion shot would be a fairly thin cut, object ball on rail. This would be where the "side" of the object ball appears to be in one place, but if you view the shot from above, the correct place to aim becomes more apparent. What do you think?



=========================

Alfie
06-09-2006, 05:38 PM
<blockquote><font class="small">Quote heater451:</font><hr> [some things about aiming, optical illusions, and such]

What do you think? <hr /></blockquote>Have you tried to make the CB and OB line up to the pocket at the moment of contact? You might have to adjust that alignment very slightly for throw.

Or you can draw a line from center pocket through the OB center to a point on its far side, and then make the CB hit the OB there. You may have to adjust that contact point very slightly for throw.

sofy60
06-10-2006, 02:30 PM
physics never lie. If you use no spin as you allege and aim correctly its going to go in the hole no matter what the ball placement. Only spin can alter the direction of the object ball. Your slow stroke maybe dead or have lack of form while your stronger stroke maybe a better one in your case. no optical illusion on a pool table believe it.
outside english you must hit a little fatter.
inside english you must hit a little thinner
as the spin of the cue ball with throw the object ball a little.

heater451
06-12-2006, 05:04 PM
<blockquote><font class="small">Quote Alfie:</font><hr><hr /></blockquote>Have you tried to make the CB and OB line up to the pocket at the moment of contact? You might have to adjust that alignment very slightly for throw.<hr /></blockquote>I have not tried that, probably because. . .<blockquote><font class="small">Quote Alfie:</font><hr>Or you can draw a line from center pocket through the OB center to a point on its far side, and then make the CB hit the OB there. You may have to adjust that contact point very slightly for throw.<hr /></blockquote>This is pretty much how I line the shot up, but I would expect contact-induced throw to help, while I appear to be getting some kind of spin-induced throw--although I am not imparting extra side-spin.



================================

Alfie
06-12-2006, 11:04 PM
<blockquote><font class="small">Quote heater451:</font><hr> <blockquote><font class="small">Quote Alfie:</font><hr>Or you can draw a line from center pocket through the OB center to a point on its far side, and then make the CB hit the OB there. You may have to adjust that contact point very slightly for throw.<hr /></blockquote>This is pretty much how I line the shot up, but I would expect contact-induced throw to help, while I appear to be getting some kind of spin-induced throw--although I am not imparting extra side-spin.<hr /></blockquote>Then methinks you are aiming or executing incorrectly. /ccboard/images/graemlins/grin.gif

cushioncrawler
06-13-2006, 06:56 PM
That sort of shot iz often a problem in English Billiardz. The qball iz close to the cushion -- we probably hit downwardz here a bit more-so than uzual. The bridge iz a problem -- if we place our bridge on the bed our fingerz are allmost touching the qball -- if we place our bridge on the rail, then there iz a lot of cue waggling around in mid-air. But i find 2 problemz in this sort of situation.

If we make a one-finger-bridge, ie the cue sliding along the right-hand-side of our one-finger, and sliding along the top of the rail, then the qtip will tend to go thru to the right. We will contact the qball a little right-of-center, with some right-hand-english -- the qball will swerve to the right, and will overcut the ball, the right-hand-spin reducing the normal throw hence making the over-cut even worse. All of this applyz to a right-handed-player. If u are a lefty then i would be baffled. And of course if u uze a loop-bridge here, then my comments are irrelevant.

The above applyz for a slowish sort of shot, which iz what u said u played.

If the one-finger stuff applyz, then the over-cutting would be worse if u had a cue with a professional taper, koz of the long overhang here, koz the tapered bit of the cue gets into the act, very late here, but with a vengeance.

In the shot that u show, if u hit very hard (instead of soft), u might get a "perfect" rezult, or even under-cut the ball. Koz, there would be lots of squirt (the qball squirts to the left a lot) but not much swerve at that shortish range (the qball swerves to the right a bit).

I was going to say -- your shot was near the end of the table -- here the lighting (which iz mainly from the left, uzually) might be causing a shadow on the right-hand-side of the qball. If so, then u will tend to see the center of the qball left of where it really iz. But now i realize that this optical illuzion would tend to give an under-cut in your shown shot, ie it would tend to negate the "one-finger-bridge" problem that i mentioned above. Perhaps it might raize its ugly head if u are hitting very hard. Forget i mentioned it.