I just came across this method to pocket balls. Has anyone tried this method of aiming? If so what’s your opinion?
Double the Distance Aiming ???
- Thread starter Brookeland Bill
- Start date
If you mean aiming the CB’s center twice the distance from OB center as the intended OB contact point…
That’s a well known aiming method that’s geometrically correct for spinless shots, but must be adjusted (aimed slightly thinner) to account for contact induced throw.
pj
chgo
patrick is being modest
dr dave used one of patrick's pics on his site in the discussion on the topic
kudos patrick
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I actually had to read the pic on the right a few times to get it
you are welcome patrick …
Doubling-the-distance in from the edge is useful for cuts thinner than half ball - instead of aiming the CB’s center at a point off the edge of the OB, you can aim the inside edge of the CB at a point on the OB. The thinner the cut the smaller the “measurement” using edges.
pj
chgo
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tomatoshooter
Well-known member
I'll have to try that. I'm typically visualizing the location of the center of the cue ball but sometimes it's hard to aim when the center of the cue ball will be far outside the object ball.
tomatoshooter
Well-known member
I started paying more attention to the overlap and aiming the edges and it works! I'm not really doing the double the distance thing, just visualizing the path of the edge of the cue ball instead of the center of the cue ball. When aiming with the edges, do you move your head so that your vision center is over the edge, or do you stay centered?.
I actually don't aim that way, just know the geometry of how it works. I keep my vision centered over my stick so I can see precisely where it's pointed, and I learn where to point it through practice, usually by "measuring" a distance from the OB contact point, which I find easy enough to visualize.
pj
chgo
I think I keep my head in the same place but my attention shifts to the edges.
tomatoshooter
Well-known member
That's what I'm doing. It's a new thing but I'm already getting good results.
Oikawa
Well-known member
Been using double the distance as my primary aiming method for some months now and have had good results with it. I used to aim 100% by feel before it, but especially on close cuts and awkward angles (back-cuts, thin shots etc.) I am much more effective with this than just aiming only by feel.
My method is to start from the opposite (pocket) side of the contact point (furthest red cross from the aim point in the image), then move in equal steps from there (center OB, contact point, aim point). Movement between each point is the same distance in both X and Y axis. Using this extra step (opposite contact point) at the start allows for better feel of the correct distance for the last step, because you are doing three shifts instead of just two. To perform the system, I fix my gaze at the points, moving from one point to the next with a steady rhythm (slower for tougher shots, quicker for easy shots), once I am at the final aiming point I will perform an adjustment by shifting the aim point sideways if needed (e.g. accounting for throw/sidespin), and then go down on the shot.
More generally speaking about my own game, I used to think that feel-based aiming was the ideal way to go for me. And while it worked well some days, it has it's weaknesses under pressure. The issue is that with feel-based aiming, it often works the best the less you are conscious about it. And being under pressure sabotages that, turning competitive pressure into a negative feedback loop. But with a conscious aiming method, the extra focus/self-awareness under pressure will actually do me a favor, I can just channel that focus into the aiming method and trust it is correct, which turns into a positive feedback loop instead.
Just my two cents, not trying to make too general claims about conscious vs. subconscious aiming, everyone has their own way. But for me this shift back to conscious from subconscious seemed to elevate my game up a noticable amount.
The reason I find this method better than just using plain ghost ball is that I am horrible at visualizing the ghost ball. Some degree of aphantasia perhaps.
For context, I am playing at about 620-640 fargo speed. Probably improved like 20-30 points within the last year. No real rating because the tournaments I play in aren't registered to fargo, but this is based on relative performance compared to people that are in the system.
My method is to start from the opposite (pocket) side of the contact point (furthest red cross from the aim point in the image), then move in equal steps from there (center OB, contact point, aim point). Movement between each point is the same distance in both X and Y axis. Using this extra step (opposite contact point) at the start allows for better feel of the correct distance for the last step, because you are doing three shifts instead of just two. To perform the system, I fix my gaze at the points, moving from one point to the next with a steady rhythm (slower for tougher shots, quicker for easy shots), once I am at the final aiming point I will perform an adjustment by shifting the aim point sideways if needed (e.g. accounting for throw/sidespin), and then go down on the shot.
More generally speaking about my own game, I used to think that feel-based aiming was the ideal way to go for me. And while it worked well some days, it has it's weaknesses under pressure. The issue is that with feel-based aiming, it often works the best the less you are conscious about it. And being under pressure sabotages that, turning competitive pressure into a negative feedback loop. But with a conscious aiming method, the extra focus/self-awareness under pressure will actually do me a favor, I can just channel that focus into the aiming method and trust it is correct, which turns into a positive feedback loop instead.
Just my two cents, not trying to make too general claims about conscious vs. subconscious aiming, everyone has their own way. But for me this shift back to conscious from subconscious seemed to elevate my game up a noticable amount.
The reason I find this method better than just using plain ghost ball is that I am horrible at visualizing the ghost ball. Some degree of aphantasia perhaps.
For context, I am playing at about 620-640 fargo speed. Probably improved like 20-30 points within the last year. No real rating because the tournaments I play in aren't registered to fargo, but this is based on relative performance compared to people that are in the system.
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If I recall correctly, the system breaks down at short distances (less than 15" CB-OB). Also, any error in estimation of the contact point gets doubled.
I find it to be useful for thin cuts.
Somewhere on Dr. Dave's site there is a whitepaper (copyrighted, even) that details the geometry and points out the short distance limitations.
I find it to be useful for thin cuts.
Somewhere on Dr. Dave's site there is a whitepaper (copyrighted, even) that details the geometry and points out the short distance limitations.
Oikawa
Well-known member
I think this depends on how exactly you do it, in my case at least since CB distance is irrelevant there's no error from being close or far. I can see if you use the CB/cue stick imagery somehow then distance starts causing errors.
I'm relying on memory from 15 years ago, but I believe there is a problem at close distances because the method (as described) does the aiming based on the plane perpendicular to the CB-OB line. As the CB-OB distance shortens, the difference in orientation between this plane, and the plane perpendicular to the CB-Ghost ball center (which is what makes for the proper "aiming plane") becomes significant.
This is why Alciatore has been critical of this approach: If you have to estimate the ghost ball center to make it work, then why not just estimate the ghost ball center and toss the rest?
IMO, nothing wrong with using double the distance aiming, but practitioners should be aware that compensation may be needed for short CB-OB distances.
This is why Alciatore has been critical of this approach: If you have to estimate the ghost ball center to make it work, then why not just estimate the ghost ball center and toss the rest?
IMO, nothing wrong with using double the distance aiming, but practitioners should be aware that compensation may be needed for short CB-OB distances.
That's really a visualization error. Center-to-edge aim produces a cut that's 30° from the center-to-edge (halfball aim) line, no matter how far apart the balls are. We tend to think of it as 30° from the center-to-center line, but moving the CB along the center-to-center line changes the center-to-edge direction, and therefore the cut's direction.
This is shown in the pics below - with the CB staying on the center-to-center line, the 3-diamond shot goes center pocket, the 2-diamond shot goes to the right side of the pocket, and the 1-diamond shot misses the pocket. All of them are 30° cut angles from the center-to-edge line.
pj
chgo
Shots executed on VP4
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Even if the shot length shortens along the CB-GB line and there is no change in cut angle, the double the distance method has some pitfalls. See page 4-5 of
https://drdavepoolinfo.com/resource_files/Don_Smith_PIM.pdf.
JAL also did a thorough error analysis in this thread (see posts 58, 59):
https://drdavepoolinfo.com/resource_files/Don_Smith_PIM.pdf.
JAL also did a thorough error analysis in this thread (see posts 58, 59):
Oikawa
Well-known member
I read through the PDF and it appears that the incorrect version does some faulty geometry indeed (as seen in the image at page 4 of the PDF) cumulating in error the closer you are to the CB. I'm not fully sure why one would do it the faulty way in the first place, it just seems like adding an error component for no reason. But whatever that reason is, there exists a simpler visualization which isn't faulty, which Dan also mentions in that PDF:
"Referring again to Figure 5, in the modified DTD method the player no longer estimates the length L then doubles it. Instead,
the player estimates the length of line ON, (the radius of the object ball). The player then doubles this distance, along the line
ON, to find the aiming point G - the center of the ghost ball. (Note that this process is essentially the same as using the ghost
ball method described earlier.)
Estimating the location of point G is difficult for some. Thus, players may prefer to use some other approach when the cue
and object balls are close together. However, one strong advantage of using the modified DTD described here is that this
approach will always work, regardless of the proximity of the cue and object balls."
So his point is that this geometrically correct double-the-distance is better (removing the error), but effectively the same as just visualizing the ghost ball. But that's exactly the point for me, I struggle at visualizing the ghost ball, but am good at visualizing the contact point and doubling that distance in 3D space, so this procedure lets me figure out that same point without having to ever visualize the ghost ball.
So yes, for those who are good at visualizing the GB I can imagine the confusion in why they would go through the steps of visualizing the distances between multiple points just to end up at the same place, but for those who can't create a visual image of the ghost ball (aphantasia or w/e, different brains for everyone), this is very useful.
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I know this is a resurrected thread, but I wound up looking at the Don Smith, Double-the-Distance PDF, and I think there is something missing--the 'frame of reference' for his diagrams is inconsistent with the layout of the balls. In Patrick Johnson's graphics, the cue ball location is offset laterally from the object ball--for the particular example(s), the cue ball path is set up parallel to the long rail. However, in Figure#5 of the PDF, the cue ball is directly inline with the object ball. I would need to get out some paper and a compass to check, but I think this would change the length of line E (the amount of error between A and A'). [Note: The offset setup is easily understood from PJ's "Parallel Lines" graphic, which is also found on Dr Dave's site.]
Of course, this would not invalidate the concept of an error at close distances, but it seems like an oversight when considering DTD as a system for aiming. However, as diagrammed, it would appear that the shooter is expected to step to the side of the cue ball to determine the measurement lines, which is not realistic.
Of course, this would not invalidate the concept of an error at close distances, but it seems like an oversight when considering DTD as a system for aiming. However, as diagrammed, it would appear that the shooter is expected to step to the side of the cue ball to determine the measurement lines, which is not realistic.
there a re few steos you do that i dont under stand
first you say
start from the opposite (pocket) side of the contact point
is that on the part of the ball you cant see?
if you mean equal from centerline opposite from the side the contact point is on
dont then have to see the distance from vertical axis the contact point is first
and then use that distance to determine your second point ie the point opposite the contact point
then if i understand you you go from that point opposite the contact point to the contact poin and then to the aim point
correct please what i am misunderstanding please....
last your X's are on a diagonal
shouldnt they be horizontal on the equator?