Swing speed and PTI score

[trumb1mj]

If SkyTrak cannot measure swing speed, why even show it? Tonight I was hitting my 54* wedge and 7i. Here were the numbers:

54
ball speed: 91
club speed: 90
PTI score: 1.016

7i
ball speed: 120
club speed: 87
PTI score: 1.39

SkyTrak_Seth I'm starting to worry about the accuracy of SkyTrak. These numbers make no sense at all...

[trumb1mj]

These numbers looked like this for several shots. There wasn't a few anomalous shots throwing off the averages.

[skytrakali]

ST doesn't measure club speed - the only speed it measures is ball speed. The club speed is inferred from the measured parameters on the ball (speed, spins, trajectory) using a regression algorithm. Often this will be close but sometimes it will be way off. For example, I am practicing my pitching at the moment and when I was hitting PWs with 9 o'clock arms yesterday two of my PTI scores were 0.88 and 1.80 - both essentially impossible. I've found that for wedges things are more often crazy than for longer clubs.

Bottom line: I will look at the club head speed, but not very hard. I am very happy that ST is very accurate in what it measures - but it can't and doesn't measure club head speed.

[Dan McWhirter]

Make allowance for launch angle...A high launch angle will show a slow ball speed in the SkyTrak's horizontal measure

[trumb1mj]

Again, why display it? These numbers only lead to confusion and make me suspect that SkyTrak is not all that accurate...

[dagratest816]

its hard to think the skytrak is accurate on something it says it doesnt measure. what are you thinking isnt accurate? yardages carry spin?? can you be a bit more specific. everybody knows the skytrak isnt accurate with clubhead speed because it says, they dont measure club head speed. Want accurate clubhead speed buy a skypro and hook it up for more measured accuracy. Just look at ball speeds launch angles and spins and carry yardages for skytrak. you havent said one thing about those that you are thinking are inaccurate.

[frackh]

The display of the club head speed w/o the SkyPro is just novelty. It's not measured by Skytrak so the accuracy is nil. But with the SkyPro, it's useful to have it displayed. Unless they enable toggling stuff on/off, ignore it if you don't have the SkyPro (or R-Motion in the future).

[trumb1mj]

its hard to think the skytrak is accurate on something it says it doesnt measure. what are you thinking isnt accurate? yardages carry spin?? can you be a bit more specific. everybody knows the skytrak isnt accurate with clubhead speed because it says, they dont measure club head speed. Want accurate clubhead speed buy a skypro and hook it up for more measured accuracy. Just look at ball speeds launch angles and spins and carry yardages for skytrak. you havent said one thing about those that you are thinking are inaccurate.

Did you look at my data? You’re telling me to ignore stats their main display panel that look absolutely bonkers? Just hide clubhead speed and pti and display height. Problem solved.

[Morini]

Ball speed is dead on for pga tour 7 iron, a touch high for smash. Likely because shot launched a bit lower than 16.3 degree tour average. Just as for the other club data, if the ball is struck in the middle of the face with a reasonable aoa, the calculation will be close.

[butette]

I tend to agree with the OP. If the data is not reliable, it is pointless to display it given that screen real estate is tight and more useful information can be shown (like height). Why show a club speed of 90 for a 54* wedge?

[jut111]

Cause clubhead speed puts a*ses in the seats so to speak. I agree with you, but that's the reality.

[RicS]

I had the same issue with club head speed in the loftier irons. If you find club head speed important, 'sport sensors swing speed radar' used in tandem with ST does a nice job. It sits off on an angle and doesn't interfere with ST camera area and displays only the swing speed of the club in use.

[trumb1mj]

I actually use my SSR at all times with my ST.

[trumb1mj]

My original point was: If there is something that is not measured and is a best guess, why force us to see it on the main driving range panel? It frustrates me that new features are being added without allowing us to customize the driving range view... Shot height is far more important than a bogus swing speed measurement.

[SkyTrak_Seth]

Most of the responses here are on point. If you're really serious about the numbers, focus on what we measure. We give it our best guess on club speed (and PTI is just a factor of this). On solid struck shots, it's actually quite accurate. But put as much into it as you wish knowing that it is a calculated number.

That said, it looks like some of the CHS tweaks for higher lofted clubs are not performing well on off-center hits, so I'm going to roll back those changes in v3.1.1 and that should bring those PTI numbers back a little closer to reality.

I think you'l be happy in our next release regarding shot height. But you know that's a calculation too though, right?

[trumb1mj]

You measure spin, launch angle and ball speed--height should be a much more accurate calculation I would assume.

[SkyTrak_Seth]

Environmental/atmospheric conditions aside, yes, we have a much better shot at Max Height than club data. But it is still a calculated number.

[FaultyClubs]

...But put as much into it as you wish knowing that it is a calculated number...

Knowing it's a calculated number doesn't tell people much. There's nothing wrong with a calculated number IF a) enough inputs are measured for a deterministic model, and b) those inputs are measured accurately enough for acceptable accuracy in the final number (ie actionable)

Maybe Skytrak could tell users the uncertainty for each calculated number. Or color code them or something (ie. green calculated number means the engineering accuracy is good enough for a user to make swing changes based on the number, yellow means marginal and red means for information only.) Height might get a green while PTI might get a red for example.

Just a suggestion since telling the user to figure it out doesn't seem that useful.

[SkyTrak_Seth]

Knowing it's a calculated number doesn't tell people much. There's nothing wrong with a calculated number IF a) enough inputs are measured for a deterministic model, and b) those inputs are measured accurately enough for acceptable accuracy in the final number (ie actionable)

Maybe Skytrak could tell users the uncertainty for each calculated number. Or color code them or something (ie. green calculated number means the engineering accuracy is good enough for a user to make swing changes based on the number, yellow means marginal and red means for information only.) Height might get a green while PTI might get a red for example.

Just a suggestion since telling the user to figure it out doesn't seem that useful.

It's a good idea, but at the end of the day we know what the ball is doing. We have no way of knowing for sure what caused that - did the player just hit it thin, soft, or did they make contact with the mat prior - without being able to measure the club directly, any estimation of the accuracy of the club data would be only as good as the calculation itself.

[JackedUpSwing]

Not sure why people can't understand this... People.. its very simple. If you made clean contact with the ball, in the center of the clubface, then their estimated swingspeed is probably accurate! Otherwise, ignore it. Why is that so bad? What does your SS matter anyway? If you swing 1000mph but miss the ball does that do anything for you? Focus on what matters BALLSPEED. If you hit a good ball, felt like you made good contact and wanna make note of what your swingspeed might be giving perfect contact? Sure take note! Is knowing your swingspeed going to help you improve your golf swing? Probably not...

[jut111]

well said jackedup. The infatuation with clubhead speed baffles me. Who cares, ball speed is king.

[FaultyClubs]

When working on increasing club head speed it is easy to have a higher CHS but lower ball speed. It takes time to dial in a new swing. An accurate CHS leads to an accurate Smash Factor. A lot of people would get higher ball speeds by concentrating on SF rather than trying to increase their swing speeds. The list goes on... Also ball speed may be king on the driver but not so on wedges. But it's all moot since the Skytrak doesn't measure club parameters, for actionable data it's best to focus on what Skytrak really measures.

The color coding idea was an attempt to reduce confusion. The current push by Skytrak to add calculated data may hurt them in the long run. Newbies and non-technical golfers (ie 99%) won't make the distinction which may lead to an erosion of the Skytrak brand as people lose confidence in its readings.

[trumb1mj]

"Not sure why people can't understand this... People.. its very simple. If you made clean contact with the ball, in the center of the clubface, then their estimated swingspeed is probably accurate! Otherwise, ignore it. Why is that so bad? What does your SS matter anyway? If you swing 1000mph but miss the ball does that do anything for you? Focus on what matters BALLSPEED. If you hit a good ball, felt like you made good contact and wanna make note of what your swingspeed might be giving perfect contact? Sure take note! Is knowing your swingspeed going to help you improve your golf swing? Probably not..."

No, actually this isn't true AT ALL. If I make good, clean contact with wedge I see CHS that exceeds ball speed with my wedges. That is not possible. It's confusing and leads to me lose confidence in SkyTrak. If CHS cannot be calculated accurately, it should be excluded from the main screen (or we should at least have the option to remove it).

[wbond]

It’s really that hard to ignore? On wedges, pretty certain it’s absolutely possible for club head to go faster than the ball. If your hitting a high flop with a 58 or 60 easily doable. Also believe protee system has issues sometimes because the club passes through the zone before the ball does on these shots.