Visualizing OB Contact Areas

[EagleMan]

A question for PJ or others:

In addition to distance-to-pocket, does cut angle effect the margin of error?

It seems to me that a thin 70-degree cut shot has a smaller margin of error than a 15-degree cut shot.

If so, then total-margin-of-error is distance-to-pocket times cut angle, if you're so inclined. Again, useless information but so is 99% anything having to do with numbers. But it's fun to think about.

PJ and/or Dr Dave may chime in here with more definitive responses, but I think the answer to your question as to whether the margin of error is altered by the cut angle is a definite yes.

CIT (Collision or Cut Induced Throw) varies with the cut angle BUT it can be altered by several factors so it's quite a subject to study.

EagleMan

 

[naji]

A question for PJ or others:

In addition to distance-to-pocket, does cut angle effect the margin of error?

It seems to me that a thin 70-degree cut shot has a smaller margin of error than a 15-degree cut shot.

If so, then total-margin-of-error is distance-to-pocket times cut angle, if you're so inclined. Again, useless information but so is 99% anything having to do with numbers. But it's fun to think about.

It is not cut angle as much as how much pocket you have, an OB at center line of table has max pocket available, but OB near the rail have almost less than 1/2 a pocket the margin for such a shot is small
The problem is not aim as much as where to aim factoring all variables.

 

[klockdoc]

Because pockets are bigger than the balls we shoot into them, our target on the OB is not a pinpoint but a small arc of the equator - the OB contact point is really the OB contact area - its size is the margin of error for that shot.

We hear the terms OB contact area and margin of error frequently on AzB, but what do they mean? How small are these contact areas - can they be seen by the naked eye? Does it matter?

I don't know if it matters, but I know a quick way to visualize how big the OB contact area is for any shot:

To visualize the OB contact area for the spot shot pictured below:

- Imagine the OB centered where it is but enlarged until its equator touches the pocket (the big hazy white disc below).

- Visualize the size of the small segment of the enlarged equator that's between the pocket points.

- Now imagine that enlarged OB is really the normal size OB on the spot and you've just zoomed in to get a close look at the size of the contact area - in fact that's exactly what you've done. The contact area's actual size is that same small fraction of a normal size OB.

pj
chgo

View attachment 251207

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How does this correlate with CTE and BHE? :grin:

 

[Patrick Johnson]

A question for PJ or others:

In addition to distance-to-pocket, does cut angle effect the margin of error?

It seems to me that a thin 70-degree cut shot has a smaller margin of error than a 15-degree cut shot.

It's the same "pocket" margin of error (the same size "contact area" on the OB) but the shooter sees a smaller cross section of it because it's turned sideways (just like the pocket opening is smaller from any angle but straight on). So yes, a cut shot has a smaller "shooting" margin of error than a straight shot.

If so, then total-margin-of-error is distance-to-pocket times cut angle, if you're so inclined.

OK, I guess.

Again, useless information but so is 99% anything having to do with numbers. But it's fun to think about.

Visualizing OB contact areas doesn't have anything to do with numbers - it's just a visualization exercise. It doesn't suggest any obvious aiming or shooting methods, but so much of this part of pool is accomplished subconsciously that any info may be important, even if your "conscious computer" can't immediately see how.

pj
chgo