Exit Point Calculation

[Mike White]

I was watching a video talking about targeting.

http://www.youtube.com/watch?v=w62JZ...eature=related

They used a formula to decide where you wanted the ball to be (which board) at the end of the oil pattern.

They came up with length-31.

Does anyone here know what they are basing their numbers on?

They make the claim that 4 degrees, 5 degrees, and 6 degrees of angle entering the pocket give the best probability of carry.

What I don't see, is how the length-31 is related to the angle of entry.

Lets take a 41 foot pattern as an example. They recommend having the ball on the 10 board at 41 feet. But they show examples of people hitting that point from multiple angles.
That means different angles into the pocket. There must be something I'm missing.

If everyone one is hitting 10 board at 41 feet, wouldn't I be better off lining up for 11 board at 41 feet and using the 10 board as bit of extra hook in case I made an error. As others start adjusting in because of the oil moving, I just need to move in to stay ahead of them.

The idea that everyone should be playing the same board at any specific distance just blows me away for two reasons, we all throw the ball different, and new balls suck up oil.

[bowl1820]

Does anyone here know what they are basing their numbers on?

The exit point formula is from a Joe Slowinski article and is based on Neil Stremmel's article, Entry Angle, Part 3: USBC Research Shows Where Your Ball Should Be to Achieve the Best Angle. Where Stremmel shares data from USBC research on points that maximize 4, 5 and 6 degrees of entry angle

This article is about where it started, the formula was later simplified to the one you seen (The math is simplified by using Pattern Length-31 = Exit Point.).-
http://bowlingknowledge.info/index.p...d=20&Itemid=46

More explaining about it in this article in step #1
http://bowlingknowledge.info/images/...eting_2007.pdf

Excerpt from "3-Point Targeting for Advanced Lane Play" by Joe Slowinski:

Step # 1: Determine the Exit Point Based on the Pattern Length
EXIT POINT = Pattern Length – 35 + 4
After reading Neil Stremmel’s article in the April issue of BTM, I immediately
reflected heavily about the implication of this research. The article featured
more than the exit point findings but I felt strongly that the exit point had huge
implications for lane play. In essence, this research creates a new term that
bowlers should be aware of, the exit point. The exit point is the board location
in which the ball should leave the oil, at the end of the pattern, to maximize the
chances of hitting the pocket.
In a nut shell, Stremmel discovered that the exit point was the same for all
players regardless of style. For example, to maximize pocket percentage, high
speed and high rev players had the same exit point as low speed and low rev
players. True, the high speed and high rev players had a breakpoint further
down the lane due to the length of the ball push past the pattern caused by
presence of both speed and revs. But, the ultimate exit point was the same.
From the findings presented in the April issue, I rounded-off the data for the
exit point locations for 5 degrees of entry angle. Stremmel presented three
data sets, including 4, 5 and 6 degrees of entry angle. Presented data
illustrated that a bowler had margin of error at the end of the pattern. So, I
used the middle set showing exit point values achieving 5 degrees of entry
angle. This would provide the bowler with miss, at the end of the pattern, left
and right. With this approach, the data fell into a simple formula, pattern
length – 35 + 4. Rather than using pattern length minus 31, I wanted to retain
the accuracy of the data set in which 35 is the base. Since most patterns a
bowler will face are between 35 and 45, this will work.
The biggest benefit from using the exit point to determine where to play the
lane is your ability to maximize the margin of error hitting the pocket as well as
choosing a more appropriate focal point for the lane condition. In regard to the
exit point, at 35 feet you actually have nearly 2 boards to the left and 2 boards
to the right to hit the pocket with between 4 and 6 degrees of entry angle. But,
of course, you have to play the lane properly by choosing the axis rotation,
speed and revolutions that match the bowling ball and lane.

They make the claim that 4 degrees, 5 degrees, and 6 degrees of angle entering the pocket give the best probability of carry.

That is based on studies done by the USBC on Ball motion and entry angles and carry etc.


See the Entry Angle info thread also
http://www.bowlingboards.com/threads...ht=entry+angle

also check this
http://www.insidebowling.com/coaching/tips_tip_022010

What I don't see, is how the length-31 is related to the angle of entry.

Lets take a 41 foot pattern as an example. They recommend having the ball on the 10 board at 41 feet. .

The exit point is just that, the point where you want the ball to come out of the oil, It's not where you hit the entry angle. Once it hits that exit point using various launch angles. Then the ball will travel distance X out of the oil and turn (at the break point) to line up with the desired entry angle.

But they show examples of people hitting that point from multiple angles. That means different angles into the pocket. There must be something I'm missing.

No their using different launch angles to get to and hit the same exit point, that's not the same as the entry angle (meaning the angle into the pocket).
As said above:
In a nut shell, Stremmel discovered that the exit point was the same for all players regardless of style.

[billf]

There is no formula perfect for everyone but that formula will get most people darn close. The thing many bowlers don't realize is that board is where you EXIT the pattern and not your break point. The different angles based off of the different start positions take into account the different styles needed to play those lines. A stroker won't be standing on the 40 board and swinging out to the 10 board. That style just isn't compatible to the tilt, rotation, etc needed to play that line.
One board on a sport pattern can change your entry angle by more than you think. That one board can and may prevent you from even hitting the pocket. Most THS patterns do have around a 4 board area of play. Just know which direction that play goes for you before hand. I personally use to play at the far left end of my margin of error. I could miss right and be ok, miss left and wowzers.
Reactive resin balls do suck up oil fast. That's why adjustments are made so often. There are times when everyone else moves their feet left (keeping the same target), I will move my feet and target right using their break point area as kind of a backboard for mine.

[bowl1820]

Also this is a reply by Joe Slowinski to a discussion on the Hammertalk board. Slowinski registered on the board and provided this response.

Bowling_Coach
Be sure to read the article on the Quiet Eye. I am currently writing a follow-up to this article with some important new findings as well as recommendations on avoiding the choke in important moments or competition settings. The quiet eye is an important element.

You PL - 31 to establish the general area down the lane. In essence, think of having 1 board right and 1 board left at the exit point. For example, your 44 foot example would be something in the range of 12, 13, 14 at 44 feet.

One method to judge 44 - 45 feet is to envision the half way point at 30 feet. Take the distance, in your mind, from the foul line to the middle of the 4th arrow. Now, imagine adding this distance to 30 feet.

If you are on ProAnvilane, the end of the pro target on board ten is approximating this distance.

Now, be sure to choose a focal point that allows the ball to move through the exit point area. With the quiet eye technique, you will be able to more aptly hit the line that you intend.

The exit point provides guidance not absolutes.

(*) If the lane is hooking or has bump, you can play it like it is a shorter pattern. Wood will hook.... Old synthetic are sufficiently scratched enough to have a track. HPL will hook....

(*) Conversely, if the lane seems tight, move in and play it like a longer pattern.

And, general player characteristics will also apply.

(*) A speed dominant bowler needs to play the pattern like it is longer.

(*) A rev dominant bowler needs to play the pattern like it is shorter.

I hope this helps.