Should the Stimpmeter Measurement Criteria be expanded?

[John Chilver-Stainer]

A thought that has been bugging me for some time is the one-dimensionality and the over simplistic presentation of the Stimpmeter as the “Green Speed” definition.

The flaw of the Stimpmeter Meaurement as I see it is the fact that it takes the AVERAGE of the distance measured in 2 directions.

In my view the HIGH and LOW measurements should also be presented as part of the measurement thus taking into account, to some degree, the inclinations within the green and helping the perception that undulating greens aren't necessary slow.

So a reading could be:-

Stimpmeter Max        10 ft  6 inches
Stimpmeter Low         6 ft  6 inches
Stimpmeter Average   8 ft  6 inces

What should one call it “The Stimpmeter Divergence”?

[Adrian_Stiff]

John- I think that degree of variant would mean you have used the stimpmeter on ground not level enough, I think you should have the readings within 2 feet, probably even a foot (closer the better) for it too count as a true read of green speed. Both measurements are interesting although they are local to that green or area.

[John Chilver-Stainer]

Adrian,

I take your point that the normal practice is to measure the Stimpmeter in level areas of the greens.

However expanding the topic for the sake of discussion, the fundamental question is does the Stimpmeter Average Reading reflect the speed of the green “as a whole” and would revealing a Stimpmeter High and Low measurement help reveal the true characteristics of the green?

I suppose it would be easy enough to make a table of standard deviations for different inclinations at 1%, 2% and 3%. At least it would illustrate that down hill inclinations in greens can create higher Stimpmeter readings than on flat greens and that at certain inclinations a high Average Stimpmeter reading is unputtable.

[Joe Hancock]

John,

Who would be the intended target be of this new information? Who would it be useful to?

Joe

[John Chilver-Stainer]

I suppose the same as the one’s that want to know the Average Stimpmeter Measurement and the position of the hole in the green?

Any information which indicates the characteristics of the movement in the greens, supplementary to the Basic Stimpmeter, would be useful.

The USGA Raters categorise the movements in the greens for establishing the Course and Slope Rating  so why shouldn’t the players get some similar information?

[Adrian_Stiff]

John- I think the readings are ok up or down if you take them just singulary, but with steep slopes or even shallowish ones, you cant average.
Some of those downhill ones at Augusta might hit a 100, they might be 10 back up the same slope.
The formula is worth knowing for understanding what a degree of slope equates to roll per foot as the stimp measure rises, that way mistakes may be eradicated in the construction. I am sure we have all made greens we wish were a bit more level in places.

[Brad Klein]

The problem with any statistical reference point is that any critic can find that it is not complete or is under-representative of the phenomenon it's measuring.

Once you move away from the convention of an average measurement for the greens at one course, there's no end to the demands you could make. Why not read every green and indicate them separately, or every section of every green? Stimpmeter reads are at best suggestive of general conditions, not exhaustively indicative.

[Tom_Doak]

John:

There is, in fact, a more complex formula for determining the stimp of a green based on the two measurements ... it assumes a consistent slope (whether it's 1% or 4%) and corrects for it.  I've seen it in the USGA Green Section publication and also somewhere else.

In the original Green Section Bulletin article about it, there was also a little chart used to show what the Stimpmeter reading on a downhill putt of 1%, 2%, 3%, 4%, or 5% with greens stimping 8, 9, or 10.  This chart was quite fascinating.  At 1% it only makes a little bit of difference, but once you get up to 3%, the "effective" green speed of a green stimping at 10 was something like 27 ... and at 4% the "effective speed" was 81!!

[Tom_Doak]

Hey, it only took me three clicks to find the formula, which is as follows:

Stimp speed equals 2 times (distance uphill) times (distance downhill),
divided by (distance uphill) plus (distance downhill).

Sorry, I don't know how to write a formula in this format any other way.

Using the formula backwards, if a green is stimping at 10 feet and there's enough slope so that the ball would only roll five feet going uphill, the formula implies that the ball rolled downhill would go twenty feet.

[JC Jones]

Hey, it only took me three clicks to find the formula, which is as follows:

Stimp speed equals 2 times (distance uphill) times (distance downhill),
divided by (distance uphill) plus (distance downhill).

Sorry, I don't know how to write a formula in this format any other way.

Using the formula backwards, if a green is stimping at 10 feet and there's enough slope so that the ball would only roll five feet going uphill, the formula implies that the ball rolled downhill would go twenty feet.

Fascinating and thanks for the leg work.  According to your calculations at 10 feet, the Stimp "speed" in the formula above would be an "8."

[John Chilver-Stainer]

Tom,

Thanks for the lead - I checked it out myself and if I’ve found a publication on the USGA site, if it’s the same one, “Green Speed Physics” by Arthur P.Weber.

I love this kind of stuff - nothing like applied physics to spice up the day. Have you ever read the book Homer Kelly’s “The Star System of G.O.L.F (Geometrically Oriented Linear Force) or Physics as applied to the golf swing?


The Formular you quoted is apparently from A.Douglas Brede who developed it for the USGA

And below are the graphics when values are applied to the parameters.









For any one that’s interested you’ll find the info at the following web site.

http://turf.lib.msu.edu/gsr/1990s/1997/970312.pdf

Thanks again for the lead Tom - "Wikipedia" must be your middle name

[Tom_Doak]

JC Jones:  Thanks for correcting my math.  I only did the top part of the equation!

JC-S:  Thanks for finding the real info.

The one thing that's odd in those charts is that the slope on the green is presented in "degrees", not in percent of slope.  That is not the way greens are measured in the field at all.  A one degree slope is much more than a one percent slope [since a 45 degree slope is 100% or 1 to 1].

I am thinking the nomenclature in the diagrams is wrong, since the results of Figure 5 conform to what I've always been told about percentage slopes -- that at 12 or 13 stimp, anything above 3% is going to be unplayable from above the hole, but at less than 10 on the stimp you could probably cut holes at up to 4 1/2% slope.  The latter is what I learned years ago from surveying the greens at Crystal Downs.

The divergence in Figure 4 is what I was trying to describe earlier.  Look at the divergence in results between a 3% slope and a 4% slope once you get up to 10 and higher on the Stimpmeter.  At a speed of 8 it's not significant at all, but after that the difference is exponential -- because gravity works exponentially.

[Brent Hutto]

1 degree == 1.8% slope
2 degree == 3.5% slope
3 degree == 5.2% slope
4 degree == 7.0% slope
5 degree == 8.7% slope
6 degree == 10.5% slope

1% slope == 0.6 degrees
2% slope == 1.1 degrees
3% slope ==  1.7 degrees
4% slope ==  2.3 degrees
5% slope ==  2.9 degrees
6% slope ==  3.4 degrees
8% slope ==  4.6 degrees
10% slope ==  5.7 degrees

[Ken Moum]

Tom,

Thanks for the lead - I checked it out myself and if I’ve found a publication on the USGA site, if it’s the same one, “Green Speed Physics” by Arthur P.Weber.

Or, you could spring for the $600 a Pelzmeter costs and let it's processor do the calculations.

Ken

[Adrian_Stiff]

I am confused; Is a vertical slope not 100%?

In which case a 1 in 1 slope (45 degree)  is 50%.

[John Chilver-Stainer]

Usually the fall is a conversion of the fraction eg 1:100 = 1% and 1:50=2% and 1:4=25% and to take it outside the realms of normal falls 1:1=100% (45degrees) so 10:1 would be 1000%

[Adrian_Stiff]

John,  I guess the main thing to remember is 1 metre of consistent fall over a normal sized back to front green equals about 3% and that represents the limit for a 13 stimp before an actual stimp of infinity kicks in. At least I have learned some new stuff today.

[John Chilver-Stainer]

Adrian,

according to the Figure 5 the “putting degree angle at which the ball will not stop” for a Stimpmeter reading of 13 feet would be just over 4 degrees.

From Brent’s calculation this would correspond to an inclination of about 7%.

In the case you’re stating of a 3% Fall (1.7 degrees inclination) with an average Stimpmeter Reading of 13 feet the downhill slope equivalent (from Figure 4) gives a Stimpmeter Reading of about 18 feet - pretty fast !!

In the report they claim to have done testing to confirm the results in the field, and the formulars all refer to angles of inclination.

If in Tom Doak's experience a ball will roll off the green with a 3% slope at 13 Stimp then the USGA should look into their research again - I can't really comment - never having witnessed a Stimp 13 myself!!!


Sticking with the USGA a 3% with an average Stimpmeter Reading of 8 feet the downhill slope equivalent from Table 4 gives a Stimpmeter Reading of 10. Not uncontrollable.

Which all goes to prove that undulating greens with a Stimpmeter of 8 are not necessarily slow if you take into account the downhill slopes.

[Adrian_Stiff]

John I have just thought of another spanner. What about exposed sites and wind influence. That third combination, of a 13 stimp, 3% downhiller, with a hooligan up the balls ars* might be fun.

There must be a moral to the story.

[Mark Chaplin]

Adrian - a comp was actually postponed at Deal over the Easter weekend due to the wind. The greens have been running very well over the winter and were probably around 8.5 to 9.0 which is pretty good for the time of year. The wind was so strong the balls would not sit still on the greens making putting impossible.

During the Wendesday of Deal week in August last year when the greens were faster and the wind averaging 30-35mph yet this situation didn't arise.

As part of the refurbishment of the course much work is being done to return the course to it's former glory, the greens are slowly being returned to fescue grasses rather than a cocktail of thick bladed "inland grasses". Gordon Irvine demonstrated a ball running 10.0 on the stimp then on a different part of the same green barely making 7.0 thus demonstrating the importance of consistency across all the greens is far more important to me than raw speed on a carefully selected area.

[John Chilver-Stainer]

Adrian and Mark,

It seems someone is onto it.
Check this out.

Who knows maybe in the near future it will be developed as a measuring tool to check the uniformity of greens !!!



“System for enhancing the televised broadcast of a golf game

Document Type and Number:
United States Patent 6774932

Abstract:
A system for the enhancement of a televised golf broadcast, which requires: obtaining detailed topographic measurements of golf greens; inputting these data into a Geographic Information System (GIS) program, smoothing the data, and generating contours on a selected interval; storing and processing the contour data such that it may be viewed from various other perspectives; selecting a real-time televised image of a golf green from a plurality of camera positions; synchronizing and superimposing the contour database image over the televised feed; computing and processing equations of motion which take into account the location of the golf ball relative to the golf cup, the weight of the golf ball, the effect of the wind, the Stimpmeter speed of the green, and the gravitational influence of the slope of the green, to determine a path the putt can take to roll into the cup or to come to rest within 18 inches of the cup; and displaying the combined images along with the projection of the calculated ball path on a real-time televised broadcasts. Before the golfer strikes the golf ball toward the cup, this system provides the viewer with a visual image of an optimal path the golf ball can traverse to result in a successful putt. With the addition of the contours and the calculated trace of the putt trajectory, the viewer has a visual assessment of the break of the putt, without depending upon the announcers' comments. Accordingly, the viewers visual experience is substantially enhanced by knowing in advance of the player's putt, the line which the ball must take to the cup. “


I must emphasise although I find the applied physics fascinating and an important part of solving construction and maintenance problems - I still believe the actual game of golf should still contain some mystery - the player should NOT be overfed with technical information but should rely on his own intuitive judgement and wit and have the strength of character to accept his own false judgements rather than blame it on the lack of information.

As others have said the Stimpmeter should only be about monitoring and the information restricted to the supervising staff to try and achieve uniformity. There are so many variables other than the Average Stimpmeter reading - that a player can only really judge the greens speed from the practise greens and practise rounds.

The more golf courses with different speeds the better - more emphasis on golf course diversification and less emphasis on achieving the lowest score. 

[Dave_Miller]

A thought that has been bugging me for some time is the one-dimensionality and the over simplistic presentation of the Stimpmeter as the “Green Speed” definition.

The flaw of the Stimpmeter Meaurement as I see it is the fact that it takes the AVERAGE of the distance measured in 2 directions.

In my view the HIGH and LOW measurements should also be presented as part of the measurement thus taking into account, to some degree, the inclinations within the green and helping the perception that undulating greens aren't necessary slow.

So a reading could be:-

Stimpmeter Max        10 ft  6 inches
Stimpmeter Low         6 ft  6 inches
Stimpmeter Average   8 ft  6 inces

What should one call it “The Stimpmeter Divergence”?

John:
The Stimpmeter was originally invented by Mr. Stimpson as a way to try and measure consistency of greens between different courses that were played on the pro tour.  It has evolved into someithing that is a pox on the game of golf and should be retired permanently
Best
Dave

[Steve Okula]

John:
The Stimpmeter was originally invented by Mr. Stimpson as a way to try and measure consistency of greens between different courses that were played on the pro tour.  It has evolved into someithing that is a pox on the game of golf and should be retired permanently
Best
Dave

Dave, I beg to differ. The stimpmeter was indeed invented by Mr. Stimpson, but as a tool for the superintendent to gauge uniformity of greens relative to each other on a single course, not as a comparatvie with other courses. Also, it was meant to give the super a manner of measuring the effects of greenkeeping practices, such as fertilizing, watering, and topdressing, on greenspeed.

It wasn't invented to compare greens of different courses for the pro tour or any other reason.

[Jim Thompson]

Basic Stimpmeter rules:

1- If you have one, don't tell anybody.
2-  If you take readings, don't tell anybody
3-  If you are asked to get one and post readings, make your own and cut the notch a half foot higher than standard.
4-  Never let anyone see you take a reading.