Clubhead & Ball Speeds Are Correct...but Yardages Are Hugely Inflated...

[Rogala]

I am a new user, using Skytrak on a PC in direct mode.

SkyTrak is reporting my clubhead speed and ball speed for an easy 7-iron at about 76-80 MPH and 116-120 MPH respectively...which seem sort of accurate based on my swing and results IRL.

It is reporting the carry distance, however, at around 176 yards and the overall distance close to 200 yards. It should be 155-165 yards with no wind based on IRL results.

What could be going on ??

My only clue is that the RPM Backspin numbers are ludicrously low....around 2-3K RPM when I know they should be 6-7K RPM based on other simulation and Real Life results.

Has anyone else seen this sort of combined RPM lowballing and yardage inflation ?? How to get SkyTrak to read properly / correct this inflation ??

Thanks !!!

[Rogala]

Skytrak does not measure any club data so it’s best to ignore it. Also, skytrak is a camera based system and its quite accurate. Make absolutely certain your clubs are clean, it will affect spin. Use a premium ball and have the logo facing the unit. Make certain the bottom of the skytrak is at the same height as your hitting surface. This should help with your spin.

Will do tomorrow. I'll make sure all the clubs are clean and I will try positioning the ball logo right at the unit. I was hitting with a brand new Callaway ERC ball, a brand new Bridgestone ball and a brand new Vice ball earlier today when I saw the wonky (over inflated) carry and total yardage numbers....since (as soon as I saw the over-inflated distnaces) I suspected the ball...hence my trying 3 different brands.

I had the SkyTrak set up on a seperate mat right next to my hitting mat...but the top surface of both mats are exactly the same height, and the top surfaces of both are about 3/4" to 1" above a concrete floor due to the mats being mounted to a plywood base.

However (!!): I just realized that I have the SkyTrak in the metal case with feet on it.

Do I maybe need to remove the feet or just remove the other mat and put the unit with feet right on the concrete floor so that the extra feet height cancels out the plywood base height of the hitting mat ?? That way the bottom surace of the metal box would be the same exact hight as the top surface of the hitting mat.

[Rogala]

I agree with wbond. SkyTrak is a camera based unit and only measures ball data. Setup is key. The unit is very accurate. The mat will also make a difference.

Thank you for responding. The mat is a home made gel insert mat which I built based on the instuctions found on this forum page. Been using it for about 8-10 months with my Swing Caddie unit.

Perhaps it is the feet on the medal box which are causing a height differential issue and therefore resulting in some oddities ?? See above post for details on that.

As far as how the SkyTrak measures performance, it was indeed my understanding that the unit measured only ball data, not club data, namely the following parameters:

Ball Speed, Launch Angle, Backspin, and Side Spin

I have read that it then makes a best guess type calculation to come up with clubead speed and other reported parameters. The weird part about my issue is that it SEEMS to be caluclating clubhead speed about right and the measured ball speed looks OK too (well, maybe a little high)...but the predicted carry and total yarages were 15-30 yards longer than my IRL distances...and also quite differnet from the numbers my Sky Caddy is giving me (I have both set up at the same time)..

RPMs looked wonky to me...so I thought this MIGHT be a clue to determining what the issue might be.

People are mostly being helpful...

Thanks for any info you can give me...as I see you a re super experienced poster and Sim guru...

[Rogala]

3on3putt commented "You say "skytrak can never be as accurate as a camera based system." Skytrak IS a camera based system. ??"

Sorry, I meant to write "combo-based system"...as in radar + camera, and I corrected it above.

I have been using a radar based Swing Caddie system for the past 8-10 months, and have also used Trackman and Foresight equipment from time to time, plus another high end camera-based teaching system at a local club.

I bought the SkyTrak because of sim capability plus the fact that it is an inexpensive camera based system which I could use at the same time as my radar based system (as the Swing Caddie sits behind the ball) and therefore have two seperate data sets to compare. My Swing Caddie mis-reports spin numbers (although in a consistent way) and I was figuring the SkyTrak would provide me dead accurate spin numbers, but would perhaps be weaker in some other areas related to club data reporting.

[Rogala]

Fresh, white, premium (urethane cover) ball with logo towards unit? SkyTrak is very good at measuring backspin, as long as logo faces camera.

BTW, I love your website....great articles....and solid advice...

[Mirek_62]

My only clue is that the RPM Backspin numbers are ludicrously low....around 2-3K RPM when I know they should be 6-7K RPM based on other simulation and Real Life results.

Thanks !!!

Backspin has a significant effect on carry distance. You can check how it affects it here

https://flightscope.com/products/trajectory-optimizer/

The type of mattress has a great influence on the backspin. It is enough that the contact of the club head is earlier (even minimal) with the mattress than with the ball and the backspin drops dramatically.

[3on3putt]

Will do tomorrow. I'll make sure all the clubs are clean and I will try positioning the ball logo right at the unit. I was hitting with a brand new Callaway ERC ball, a brand new Bridgestone ball and a brand new Vice ball earlier today when I saw the wonky (over inflated) carry and total yardage numbers....since (as soon as I saw the over-inflated distnaces) I suspected the ball...hence my trying 3 different brands.

I had the SkyTrak set up on a seperate mat right next to my hitting mat...but the top surface of both mats are exactly the same height, and the top surfaces of both are about 3/4" to 1" above a concrete floor due to the mats being mounted to a plywood base.

However (!!): I just realized that I have the SkyTrak in the metal case with feet on it.

Do I maybe need to remove the feet or just remove the other mat and put the unit with feet right on the concrete floor so that the extra feet height cancels out the plywood base height of the hitting mat ?? That way the bottom surace of the metal box would be the same exact hight as the top surface of the hitting mat.

The bottom of the Skytrak must be level with your hitting surface. So if the 2 mats are the same height, the legs on the metal case will need to be unscrewed all the way up so that the unit can go down as low as possible. Try removing the Skytrak from the metal case and have it sit on your separate mat to ensure that the unit is level with your hitting mat and see if that makes a difference.

Also make sure to zero out the tilt and roll in the skytrak app. I don't think tilt or roll will affect spin but always worth doing anyway.

[Ronsc1985]

Of course, and I would agree with all your thoughts....although the launch monitor I was using in that particular session actually had one input the club loft data for each club as part of its set up. In the case of the Rogues, I entered the lofts right off the Callaway spec chart and it spit out smash factor numbers based on the data.

That being said, I am (sadly) aware that equipment companies today are doubling down on the same vanishing-loft game that almost every big club manufacturer has played since the 1980s....labelling a 5 iron as their 6 iron or even a 7 iron. ;-)

In my very limited experience with juiced up clubs like the Rogue, I can say that I find them waaaay too hot for my tastes. My play set irons are set up (PW to 5-iron) at 46, 42, 38, 34, 30, 26 in terms of the loft...so 2 degrees strong versus classical numbers.

You can read this link

https://www.tutelman.com/golf/design/swing2.php

for a pretty detailed explanation of the effects of loft on ball flight parameters.

[Bubba22]

Here is a search on some threads dealing with low spin and Skytrak.


https://www.google.com/search?q=skyt...obile&ie=UTF-8

[RAH5]

So are others seeing more realistic spin numbers? Curious to know because it seems a fair amount of us are seeing it pretty low.

[3on3putt]

So are others seeing more realistic spin numbers? Curious to know because it seems a fair amount of us are seeing it pretty low.

I don't pay much attention to spin except for driver. So I can't necessarily say how accurate I think the spin numbers are. But I do know that the carry distances are spot on to real life and so are the ball flights. I have 100% confidence in my unit in those regards.

I don't know if it's been mentioned here yet but make sure your grooves are clean and that you aren't launching knuckle balls because there's dirt caked in the grooves.

[Fhacker]

First level and set up skytrak per the many instructions on this site and above. Gunghogolf has an an excellent article on same. I personally have my unit on a concrete floor next to my mat and used the case legs to bring the unit up to lelvel of mat. If unit is sitting where it can shake or move when u hit u will get odd results. After that hit a series of say 10 iron shots and look at average typical ranges. Looking at individual shot parameters is useless Put ball on a tee to eliminate mat influences. Then go from there. Input average parameters into an online flight algorithm and see what the results are

[Rogala]

First level and set up skytrak per the many instructions on this site and above. Gunghogolf has an an excellent article on same. I personally have my unit on a concrete floor next to my mat and used the case legs to bring the unit up to lelvel of mat. If unit is sitting where it can shake or move when u hit u will get odd results. After that hit a series of say 10 iron shots and look at average typical ranges. Looking at individual shot parameters is useless Put ball on a tee to eliminate mat influences. Then go from there. Input average parameters into an online flight algorithm and see what the results are

OK, I just took the feet off the unit and am heading to the garage now to hit some iron shots. Will report back.

I am using the device in DIRECT mode, BTW, as my network is a little spotty in the garage at the moment. I could also try USB mode tomorrow as I just ordered an extra long active cable per something I read from Gunghogolf on another thread.

Again, thanks for your patience with a SkyTrak newbie.

I will be using the radar based Swing Caddie as well as the SkyTrak, just so I have the data being collected / reported in two different ways.

[Rogala]

OK, just hit some balls with:

a) the feet off the metal case, and the base of the unit on a support mat next to the hitting mat, therefore the same height as the hitting mat (or at least within 1/8"), and
b) the ball logo pointed at the camera.

RPM numbers are very different than earlier, with an average backspin number of around 4,000 RPMs...again lower than I expected...but this time all the calculated carry and roll yardages made perfect sense vs. my IRL experience.

The data attached below were from 10 shots off my hitting mat mounted on a plywood base (with a built-in gelpad in the hitting area to mimic going down into the turf with the clubhead) and hit with a 34 degree 7-iron. I deleted 4 other shots from the data set as I knew (via contact feel and sound) that I hit them either slightly fat or slightly thin. Shot #5 in the data set also felt like a slightly wonky one, but I left it in as it is representative of the low RPM numbers I was getting yesterday, even though the distance numbers seemed to make logical sense in the context of my other shots.

I used my radar-based Swing Caddie unit at the same time as the Skytrak, and the reported total carry distances from it were within 2-5 yards of the SkyTrak (usually shorter) for each of these shots...so I suppsoe that is a sort of 2nd confirming data point.

Thoughts ??

[Morini]

Again, low spin off mat. Hit off short tee.

[Fhacker]

Those numbers look pretty good for an amateur. Not sure what else I can say

[Rogala]

The distances look reasonable based on my IRL play...but the spin rate still seems low to me..mat or no mat...especially based on other club and ball fitting sessions I have done. See some other posts by me regarding 7-iron RPM rate data in these sessions from 2012 onward.

Also see several other posts citing threads started by users on this forum wondering about low spin reproting by SkyTrak over the years.

Reports of "lower than expected backspin" sure seem to be a real thing. If it can be corrected with set up tweaks, I am all ears and want to get the unint dialed in, as best I can.

Again, thanks for patience with a SkyTrak newbie.

[Bubba22]

Try hitting some short teed iron shots as mentioned above by Fhacker.

[Morini]

Once more, just to be clear. The skytrak is accurate. There is no inflation. When spin drops due to hitting off a mat, the ball carries further. Just physics. If you don't believe me just paste your ball data into flight scope trajectory optimizer. https://flightscope.com/products/trajectory-optimizer/