Fractional Shot "Coverage"

Patrick Johnson

Patrick Johnson

Fargo 1000 on VP4
Silver Member
Since Hal Houle's "Three Angle" aiming system debuted decades ago there has been lots of discussion and debate about how many "system" CB/OB alignments are needed to be able to make all shots. Here (in two posts) are a couple of graphics I did *cough* years ago showing (hopefully clearly) how much of the total field of cut angles the common fractional alignments (3/4, 1/2, 1/4, 1/8 CB/OB overlaps) cover, allowing for margins of error for pocket slop.

pj
chgo

Pic#1
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Nice diagrams, Patrick. In the second diagram on the first picture you have the ob close to the pocket. This is the set up that guy Mike was demonstrating with his "75%" shots video. I said you can make a large number of shots doing what he is doing and I think that image above bears that out. For just about all other shots that are farther from the pocket, though, I agree that "a lot" is not accurate.

Now when are we going to bet that I can make more than 1 in 8 spot shots? ;)
 
Nice Pat....I did similar diagrams years ago, leading up to Poolology. You can see by looking at these diagrams that most shots can be pocketed using 1/8 incremental aim points. The farther from the pocket the more you have to fine tune it....a 5/8 aim that works from 3 ft out might have to be hit a touch thinner or thicker than 5/8 at 5 ft out, which can easily be done with a little spin.
 
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BC21 said:
Nice Pat....I did similar diagrams years ago, leading up to Poolology. You can see by looking at these diagrams that most shots can be pocketed using 1/8 incremental aim points. The farther from the pocket the more you have to fine tune it....a 5/8 aim that works from 3 ft out might have to be hit a touch thinner or thicker than 5/8 at 5 ft out, which can easily be done with a little spin.
Click to expand...
Yes, adding 1/8s would add coverage, but to me that would be overkill - although I don't aim using fractions, I don't think I'd need reference angles closer than fourths apart (although the calculus might be different for Poolology estimates).

Do you prefer to use sidespin to make cut angle adjustments? To me the addition of squirt/swerve/throw to the aiming equation seems harder than making slight aim adjustments.

pj
chgo
 
Patrick Johnson said:
Yes, adding 1/8s would add coverage, but to me that would be overkill - although I don't aim using fractions, I don't think I'd need reference angles closer than fourths apart (although the calculus might be different for Poolology estimates).

Do you prefer to use sidespin to make cut angle adjustments? To me the addition of squirt/swerve/throw to the aiming equation seems harder than making slight aim adjustments.

pj
chgo
Click to expand...

I find it pretty simple to aim 1/10 of an inch left or right of any fractional aim point, whether it's a 1/4 ref or a 1/8. No calculus....just simple math and visual comparisons to known references.
 
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Thanks PJ

Great pics that show that the angular range of aiming at a cut angle to pocket the OB from one side of the pocket to the other side depending on the hit on the CB - thick to thin within that angular range. If the CB lies within the angular rang, you are set.

If the CB is in that angular range, aiming at the nominal cut angle will pocket the OB.

cut 2.JPG

Be well.
 
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Fractional shot coverage

Just Aline center to edge, edge to A,B,C,and pivot to center cue ball. Quit over thinking it and just play.
 
Valiant Thor said:
Just Aline center to edge, edge to A,B,C,and pivot to center cue ball. Quit over thinking it and just play.
Click to expand...

Or, as the OP is showing, just align straight through ccb to where you want the cb to go.

Most players don't need multiple visual lines that lead to a certain ccb (fixed cb), only to then visualize an offset line to that ccb view (1/2 tip left or right) and then pivot to a final ccb. The op is referring to a system that allows you to align straight up with a final ccb (fixed also), a one line visual, the aim line. If you can see this line, or know this line, then you'll be looking straight at the final ccb and it's fixed edges without having to choose A/B/C and then aligning offset to that perspective only to pivot to a different ccb slightly angled from your stance.

To each their own. I prefer the straight forward approach as shown in this thread. I suppose one could use the nearest quarter fraction, look straight down that line through ccb and determine if it'll be a thin or a thick shot, then do an offset pivot from one side or the other of that line to bring the cue into a corrected alignment for the shot. It would take some practice to get the pivot right to make the shot, but every method takes practice. Or, as you say, you can use CTE visuals and then an offset pivot to thin or thicken the line provided by the visuals. But that should be a different thread.
 
Valiant Thor said:
Just Aline center to edge, edge to A,B,C,and pivot to center cue ball. Quit over thinking it and just play.
Click to expand...

I'm with VT. The diagrams show that for some ball positions you must use at least 16ths in order to insure pocketing or learn to use spin on the 8ths. The systems has quite a few holes in it.


BC21 said:
.....I suppose one could use the nearest quarter fraction, look straight down that line through ccb and determine if it'll be a thin or a thick shot, then do an offset pivot from one side or the other of that line to bring the cue into a corrected alignment for the shot. It would take some practice to get the pivot right to make the shot, but every method takes practice. Or, as you say, you can use CTE visuals and then an offset pivot to thin or thicken the line provided by the visuals. But that should be a different thread.
Click to expand...

Pretty good description of Shish-Kebob. No math, no zones, no holes. Spidey made a thread about the system a few months ago.
 
Vorpal Cue said:
I'm with VT. The diagrams show that for some ball positions you must use at least 16ths in order to insure pocketing or learn to use spin on the 8ths. The systems has quite a few holes in it.




Pretty good description of Shish-Kebob. No math, no zones, no holes. Spidey made a thread about the system a few months ago.
Click to expand...

You are correct....shishkabob. But for me there are gaps in pivot systems because I'm not willing to invest hours upon hours of practicing varying pivots and visuals needed to fill the gaps. I have a friend that uses shishkabob, and he has learned over the years how to fill the gaps. He's "refined" it so that it's more accurate. My method has no gaps. I can adjust fractional aiming to within about 1/32 of a ball (using my tip as a gage to adjust aiming by a little less than a tenth of an inch). It's very accurate.
 
BC21 said:
You are correct....shishkabob. But for me there are gaps in pivot systems because I'm not willing to invest hours upon hours of practicing varying pivots and visuals needed to fill the gaps. I have a friend that uses shishkabob, and he has learned over the years how to fill the gaps. He's "refined" it so that it's more accurate. My method has no gaps. I can adjust fractional aiming to within about 1/32 of a ball (using my tip as a gage to adjust aiming by a little less than a tenth of an inch). It's very accurate.
Click to expand...

I'm sure you can work your system to fill in the gaps and make it accurate with practice. I'm pointing out that some folks rather invest their time in learning a pivot system.

Unless your systems is refined to 16ths it does have gaps. Pat's diagrams show this clearly.
 
Vorpal Cue said:
I'm sure you can work your system to fill in the gaps and make it accurate with practice. I'm pointing out that some folks rather invest their time in learning a pivot system.

Unless your systems is refined to 16ths it does have gaps. Pat's diagrams show this clearly.
Click to expand...

Oh yes, with fractions if you stick to 1/4 aim points there are large gaps that need worked out. If you stick to 1/8 aim points you eliminate gaps as long as the OB is within 2 or 3 feet of the pocket. Beyond that you need to practice hitting at least 2mm left or right of the nearest 1/8 aim point, which isn't tough when using your tip as a gage.
 
BC21 said:
Oh yes, with fractions if you stick to 1/4 aim points there are large gaps that need worked out. If you stick to 1/8 aim points you eliminate gaps as long as the OB is within 2 or 3 feet of the pocket. Beyond that you need to practice hitting at least 2mm left or right of the nearest 1/8 aim point, which isn't tough when using your tip as a gage.
Click to expand...

One can use a parallel shift of the cue to the side to about 1/4 tip and then pivot back to center for some of those gaps and then 1/2 tip....etc..:)
 
BC21 said:
I suppose one could use the nearest quarter fraction, look straight down that line through ccb and determine if it'll be a thin or a thick shot, then do an offset pivot from one side or the other of that line to bring the cue into a corrected alignment for the shot.
Click to expand...
Seems to me you need to know where the shot line is in order to offset your pivot the right amount to land on it - so the pivot is an unneeded adjustment that only adds another opportunity for error. Unless a pivot is for some other use, like "adjusting" your aim thicker or thinner from a reference angle based on feel.

pj
chgo
 
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BC21 said:
Oh yes, with fractions if you stick to 1/4 aim points there are large gaps that need worked out. If you stick to 1/8 aim points you eliminate gaps as long as the OB is within 2 or 3 feet of the pocket. Beyond that you need to practice hitting at least 2mm left or right of the nearest 1/8 aim point, which isn't tough when using your tip as a gage.
Click to expand...

Which are about 16ths.
 
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