Do you adjust your aim for different spins and speeds?

[Colin Colenso]

Not many people are aware that the angles the OB takes after impact varies considerably according to the speed of the CB and the spin on it.

Recently, with the assistance of Dr. Dave, I put together a series of plots that give a visual representation of this variation in OB throw.

Left edge is 100% Inside English, Right edge is 100% Outside English.
Top is 100% forward spin, bottom is 100% bottom spin. The center represents a sliding cue ball.

The values are contrasted against the angle the OB takes on a soft-medium speed (8km/h ~ 5mph) natural rolling shot, not the line through centres, because we rarely actually want to aim at this contact point.

The units are in inches per yard.

Slow Speed 1/8th Ball Shot. 4km/h ~ 3mph

Medium Speed 1/8th Ball Shot. 12 km/h ~8mph

Very High Speed 1/8thBall Shot. 36 km/h ~22mph​

The orange colors indicate that the OB will be directed along a thicker line (undercutting), while the bluish shades indicate that the OB will be directed to a thinner line (overcutting).

Some things to notice are:
1. A soft stun shot make cause you to undercut the shot by around 4 inches if the OB is just 3 feet from the pocket.

2. For soft and medium speed shots, heavy Outside English results in overcutting of up to 5 inches over 3 feet.

3. High power stun, follow or draw shots cause slight undercutting.

So my questions to members are:
1. Were you aware of any of this?
2. Do you ever make conscious adjustments for these changes in throw?
3. Do you think you miss often due to not taking into account these changes in throw?

Feel free to add any other thoughts, comments or questions.

Colin

Here is the Legend for those that requested it. Units are inches per yard.​

 

[s0lidz]

1. Were you aware of any of this?

Yes, most players start picking up on this as they enter the intermediate-advanced level.

2. Do you ever make conscious adjustments for these changes in throw?

Yes, you absolutely have to or you will miss shots attempting to play shape. You also can use this to your advantage when you have a blocking ball and can't see all of the object ball. You can load up on the spin and change the angle to your favor. Also, typically a little outside english on cut shots will allow you to aim directly for the pocket and not throw the angle off.

3. Do you think you miss often due to not taking into account these changes in throw?

No, though I do miss due to overcompensation (or undercompensation) sometimes. But never due to not taking into account throw and transfer of english unless I accidentally put english on the cueball. That is a miss caused by a poor stroke rather than compensation error and can be prevented by working on a straight stroke.

 

[Steve Ellis]

Not that I think about. Maybe I adjust unconciously.
As Yogi Berra said, "How can you think and hit the ball?"

 

[Colin Colenso]

No, though I do miss due to overcompensation (or undercompensation) sometimes. But never due to not taking into account throw and transfer of english unless I accidentally put english on the cueball. That is a miss caused by a poor stroke rather than compensation error and can be prevented by working on a straight stroke.

Thanks for the detailed answers S0lids! I would have answered almost the same way.

I am very happy to now have more precise data that is visually easy to read. Hopefully this means I will not be guessing the compensations so much. Hence less misses.

 

[Colin Colenso]

Not that I think about. Maybe I adjust unconciously.
As Yogi Berra said, "How can you think and hit the ball?"

Yogi is a humorous fellow, but I prefer the words of Lord Kelvin who said;

"the first essential step in the direction of learning any subject is to find principles of numerical reckoning and practicable methods for measuring some quality connected with it. I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind"

 

[Paul Dayton]

Actually, after you have played for a while, you just shoot the shot because thinking gets in the way. The sub-conscious does your aiming for you.

 

[SCCues]

You make some interesting points in your thread and I had an awful time trying to allow for deflection with different cues since most of them were slightly different.

Speed changes the aim, soft hit versus a hard hit on the cue ball and I guess you learn this from playing. Some players never pick up on it though they just keep missing certain shots.

The best solution for me to all of your points in the thread was to start using a predator shaft. I got my cue maker (Paul Mottey) to match predator shafts to my cue and this solved a lot of my aiming and ball pocketing problems. Predator shafts aren't for everyone and i'd never try to talk someone into using them, but they worked for me and my pool game.

James

 

[Colin Colenso]

Actually, after you have played for a while, you just shoot the shot because thinking gets in the way. The sub-conscious does your aiming for you.

Paul,
Don't you feel there are some shots that players avoid because they do not have a subconscious feel for the line of the shot? e.g. Long softish pots (OB must travel 6 diamonds to the pocket) with stun inside english for a 7/8ths cut shot.

I tend to think that most players, even relatively good experienced players get to know a set range of shots they can judge and avoid other shots unless they have no other options. And it is these shots that they struggle with, because they are not used to, and have no quantitative information on how to adjust for them.

 

[Colin Colenso]

You make some interesting points in your thread and I had an awful time trying to allow for deflection with different cues since most of them were slightly different.

Speed changes the aim, soft hit versus a hard hit on the cue ball and I guess you learn this from playing. Some players never pick up on it though they just keep missing certain shots.

The best solution for me to all of your points in the thread was to start using a predator shaft. I got my cue maker (Paul Mottey) to match predator shafts to my cue and this solved a lot of my aiming and ball pocketing problems. Predator shafts aren't for everyone and i'd never try to talk someone into using them, but they worked for me and my pool game.

James

Deflection or squirt is the other factor that complicates the adjustment process when english is being used.

Btw. Some testing I have done indicates that the required pivot point, when using back hand english, increases in length by about 10% for every diamond the CB has to travel on soft shots (e.g. If your cue pivot point is 10 inches, a long 6 diamond soft shot will require pivoting at around 16 inches), about 5% for medium speed and 1-2% per diamond for very firm shots.

Whether you use BHE or not, these adjustments need to be taken into account with aiming, even with a predator.

 

[Pete]

Paul,
Don't you feel there are some shots that players avoid because they do not have a subconscious feel for the line of the shot? e.g. Long softish pots (OB must travel 6 diamonds to the pocket) with stun inside english for a 7/8ths cut shot.

I tend to think that most players, even relatively good experienced players get to know a set range of shots they can judge and avoid other shots unless they have no other options. And it is these shots that they struggle with, because they are not used to, and have no quantitative information on how to adjust for them.

Most people don't practice enough. My martial arts mentor Danny always told me, "Make habbit of what others hate to do." What he means is, look at what people have trouble with and don't work on because of that, and practice it until it is your strength.

Most people don't like to fail, and those "Hard Shots" are what they fail at the most...

Pete

 

[Neil]

................

 

[Colin Colenso]

1 inch per foot max throw rule of thumb.

An old rule of thumb that I have always gone by, is that the max you can throw a ball is about an inch per foot of travel. I don't know how technically acurrate that is, but it has served me well over the years.

Neil,
From our data the maximum throw is about 6 inches per yard (2 inches per foot) thickening from the line-of-centers for a fine cut shot 1/8th ball using slow speed (CB runs about 1 table length) with about 25% Outside English stun strangely enough. With pure stun the CB actually slides across more creating less friction.

For a full ball shot, also at slow speed, around 75% of stun english (gets more throw than 100% english) results in about 4.5 inches per yard of throw, which is 1.5 inches per foot. Normally you'd be hitting the ball a bit harder than this so your 1 inch per foot rule of thumb is pretty close to maximum throw for most practical situations where you want to turn a ball.:thumbup:

 

[Steve Ellis]

Yogi is a humorous fellow, but I prefer the words of Lord Kelvin who said;

In my haste I left off a key phrase before, he actually said:

"How can you think and hit the ball at the same time?"

As to Kelvin's thoughts they're great in a controlled environment, but kind of go by the wayside in the heat of battle.
I can't enjoy the game playing it like chess, for that matter I can't enjoy playing chess like chess. If I'm not enjoying it, I'd rather be home reading.

 

[td873]

The values are contrasted against the angle the OB takes on a soft-medium speed (8km/h ~ 5mph) natural rolling shot, not the line through centres, because we rarely actually want to aim at this contact point.

I can't see any of the graphs, so most of the statements are not 100% clear to me. Are you saying that you set up a control shot, and used this as the point of reference?

Some things to notice are:
1. A soft stun shot make cause you to undercut the shot by around 4 inches if the OB is just 3 feet from the pocket.

3. High power stun, follow or draw shots cause slight undercutting.

Again, I can't see the graphs, but I am not convinced that your results accurately describe of all influences on this system. For example, a thinner vs. thicker hit on the OB may influence the result. I also think you may need to perform each of these shots at full/oblique angles and evaluate those results as well.

General Comment:
If you look at #1 and #3 by themselves - you see that speed (and NOT throw) has a significant effect on a shot. That is: #1) a soft stun = big undercut, and #3) hard stun = slight undercut. Perhaps this is a result that you did not take into consideration? That is: speed alone has caused a different result independent of the "throw" points you emphasize.

This all begs the question: What is the interplay between speed and throw? E.g., if slow speed results in undercutting, but outside english results in overcutting - what speed and amount of english gives a null effect? And at what cut angles can this effect be achieved?

Also, there is more at work than just the throw. Taking throw in a vaccuum is a nice way to illustrate the effect of spin on an object ball, but without addressing squirt, swerve, contact point, and speed, I believe the lesson is incomplete.

I believe there is additional information on these points in Jack Kohler's series on pocket billiards.

-td

 

[Colin Colenso]

I can't see any of the graphs, so most of the statements are not 100% clear to me. Are you saying that you set up a control shot, and used this as the point of reference?


Again, I can't see the graphs, but I am not convinced that your results accurately describe of all influences on this system. For example, a thinner vs. thicker hit on the OB may influence the result. I also think you may need to perform each of these shots at full/oblique angles and evaluate those results as well.

General Comment:
If you look at #1 and #3 by themselves - you see that speed (and NOT throw) has a significant effect on a shot. That is: #1) a soft stun = big undercut, and #3) hard stun = slight undercut. Perhaps this is a result that you did not take into consideration? That is: speed alone has caused a different result independent of the "throw" points you emphasize.

This all begs the question: What is the interplay between speed and throw? E.g., if slow speed results in undercutting, but outside english results in overcutting - what speed and amount of english gives a null effect? And at what cut angles can this effect be achieved?

Also, there is more at work than just the throw. Taking throw in a vaccuum is a nice way to illustrate the effect of spin on an object ball, but without addressing squirt, swerve, contact point, and speed, I believe the lesson is incomplete.

I believe there is additional information on these points in Jack Kohler's series on pocket billiards.

-td

I moved the images to another host. Should be able to see them now.

Take a look and you might have a better idea of what I am talking about. Throw depends on speed, spin and cut angle btw.

This is just one part of a complete system of adjustment which include aim & pivot adjustment. The throw plots for the various angles also vary considerably. I'm just showing the 1/8th ball cut shot plots in 3 speeds to give people an idea of how throw varies and to see what people think of this visual throw plot method which has not been done before to my knowledge.

Colin

 

[Patrick Johnson]

Some testing I have done indicates that the required pivot point, when using back hand english, increases in length by about 10% for every diamond the CB has to travel on soft shots (e.g. If your cue pivot point is 10 inches, a long 6 diamond soft shot will require pivoting at around 16 inches), about 5% for medium speed and 1-2% per diamond for very firm shots.

This seems like a complicated way of expressing the fact that the effect of swerve increases with less speed and/or more length.

pj
chgo

 

[Patrick Johnson]

If you look at #1 and #3 by themselves - you see that speed (and NOT throw) has a significant effect on a shot. That is: #1) a soft stun = big undercut, and #3) hard stun = slight undercut. Perhaps this is a result that you did not take into consideration? That is: speed alone has caused a different result independent of the "throw" points you emphasize.

CB speed alone can't explain a changed OB path - there must be some difference in the contact point (squirt/swerve) or some difference in CB/OB friction (throw). Are you saying squirt/swerve?

pj
chgo

 

[av84fun]

Colin and Dave...thanks for your always interesting studies.

td...you have hit on what I believe to be one of THE MAIN ISSUES in playing advanced pool...i.e. the interrelationship and in many cases the OPPOSITE effects of spin and squirt.

Playing advanced speed requires the use of spin... which opens up whole new worlds of positional posibilities and often allows for more moderately paced shot speeds i.e. "letting the spin do the work."

Moderate shot speeds are a hallmark of advanced players and conversely, bangers are called bangers for a good reason.

As you point out (stated in other words here by me) while outside english will throw the OB in the "thin" or over-cut direction, it will ALSO cause the CB to squirt in the "thick" or under-cut direction.

Also, error tolerance varies with distance. You can shoot a shot of a given angle with a given amount of english from 6 inches all day that you would miss by half a diamond on an 8 ft. shot.

IMHO, one of the CRUCIAL things that top players do that the rest of us are less skilled at is to master the interrelationship of squirt and throw over varying speeds and distances!

Also IMHO, while there are techniques, guidlines, cue tips and shafts that can help a great deal in mastering those interrelationships, nothing is a substitute for raw experience resulting from practice and in that case, the top pros have it all over the rest of us.

It is not unusual for champions to practice 6 hours per day.

That translates to hitting 2,000 shots per day...13,000 per week...52,000 per month or 622,000 per year.

Therefore, in their first 10 years, champions have shot in excess of 6 MILLION shots!

There are plenty of APA 9s that have not shot 2 million shots in their lives!

Regards,
Jim

I can't see any of the graphs, so most of the statements are not 100% clear to me. Are you saying that you set up a control shot, and used this as the point of reference?


Again, I can't see the graphs, but I am not convinced that your results accurately describe of all influences on this system. For example, a thinner vs. thicker hit on the OB may influence the result. I also think you may need to perform each of these shots at full/oblique angles and evaluate those results as well.

General Comment:
If you look at #1 and #3 by themselves - you see that speed (and NOT throw) has a significant effect on a shot. That is: #1) a soft stun = big undercut, and #3) hard stun = slight undercut. Perhaps this is a result that you did not take into consideration? That is: speed alone has caused a different result independent of the "throw" points you emphasize.

This all begs the question: What is the interplay between speed and throw? E.g., if slow speed results in undercutting, but outside english results in overcutting - what speed and amount of english gives a null effect? And at what cut angles can this effect be achieved?

Also, there is more at work than just the throw. Taking throw in a vaccuum is a nice way to illustrate the effect of spin on an object ball, but without addressing squirt, swerve, contact point, and speed, I believe the lesson is incomplete.

I believe there is additional information on these points in Jack Kohler's series on pocket billiards.

-td

 

[Colin Colenso]

This seems like a complicated way of expressing the fact that the effect of swerve increases with less speed and/or more length.

pj
chgo

Well it quantifies the effect. Though more complex, it is certainly more valuable.

I will be doing graphs/charts to make the process more understandable and calculable.

Colin

 

[dr_dave]

more throw resources

Not many people are aware that the angles the OB takes after impact varies considerably according to the speed of the CB and the spin on it.

Recently, with the assistance of Dr. Dave, I put together a series of plots that give a visual representation of this variation in OB throw.

Left edge is 100% Inside English, Right edge is 100% Outside English.
Top is 100% forward spin, bottom is 100% bottom spin. The center represents a sliding cue ball.

The values are contrasted against the angle the OB takes on a soft-medium speed (8km/h ~ 5mph) natural rolling shot, not the line through centres, because we rarely actually want to aim at this contact point.

Colin,

Good idea to display throw variations with the contour plots ... very visual.

For people who want to see the details of where the numbers come from, they can check out TP B.3. There, I also have some additional contour plots referenced to the line-of-centers direction instead of the medium-soft roll direction.

Also, FYI, in TP A.28 I have numerous graphs that show how throw varies with cut angle, speed, English, and spin. I like the contour plot approach, but sometimes the trends are more clear in the graphs.

If people want to learn a lot more about throw, they can refer to my 12 articles on the topic, which can be found here (August '06 - July '07):

http://billiards.colostate.edu/bd_articles​

Regards,
Dave

Again, good work!

Regards,
Dave