Trajectory

[Harbor17]

Hey Guys,

I received my skytrak last week and have spend a bit of time using it and like it. It looks like the carry distances of my irons are pretty accurate but I am concerned about the trajectory displayed. I hit my irons straight with a slight draw on the course and play to a 5hc, typically 5yrds or less but the skytrak is showing all of my shots starting left and missing my target on average 15 - 20 yards, this seems really excessive. The left spin rates are between 400 - 800 rpm's but translatet 20yrd left miss seems unrealistic, especially on wedges.

Any thoughts?

[TorchRedRob]

I'd always thought the effects of side spin were a little exaggerated on the skytrak algorithm. Particularly the ground interaction, where the majority of offline measurement will occur, if you watch how far it rolls to the side once it hits the ground. I think the e6 and JNPG flight algorithms are more realistic in that regard. I don't have experience with TGC to comment

[colinjm18]

I would say alignment of the skytrak, I know if I use the lasers on mine to align the unit everything goes left as the unit is sat at an angle to the mat. When I square the unit to my mat everything straightens out.

[DirtyGarry24]

Colinjm describes my ST setup alignment perfectly. It could be the same for the OP.

[Harbor17]

I am concerned with my device. I watched a youtube clip of someone hitting on a skytrak and their numbers were similar to the numbers my unit is showing, only my unit feedback shows 20 yard draw/hook while the youtuber's skytrak is showing 6yrd draw.

I am skeptical of the readouts from my unit as it is showing a 20 yard hook on a sand wedge shot, that is much more hook than I have ever hit on the course with such a short club. I aligned my unit to the left a bit and it seemed to help a little but I am still not happy with the accuracy of the sidespin.

Any thoughts?

[jut111]

So are you disputing the numbers your seeing or the results your seeing (dispersion) or both.

Google flightscope trajectory optimizer and plug your numbers in there. I'm willing to bet they line up pretty close to the ball flight your seeing on skytrak.

If you think the numbers are wrong well, lots have been down that path, most have been victims of indoor swing syndrome. It's very different aligning and swinging indoors then out on the course.

[teamacacia]

I'd say check alignment to make sure your ball flight and skytrak are parallel. I keep my skytrak device on its own platform (level with mat) next to the hitting mat as my mat sometimes shifts a little after a session of hitting. I am also hitting pretty close to the net and maybe that helps with the alignment? When I am taking stance with my driver, if I hold the driver in my left hand I can almost touch the hitting net. I've noticed my stance is slightly open compared to the hitting line and I'd have sworn I typically line up a touch closed on the course.

[ironFrank]

I do doubt the numbers sometimes as well.

Sometimes I got slices which are not possible cause the ball hitted the impact screen to the left and it showed me a start to the right with a push slice. I simply ignore those and dont try to correct my swing. Funny is, that the next shot hits the impact screen at the same point and the ball starts to the left...

So, I placed my slowmotion camera to record my clubface and indeed, it wasnt possible that that shot was going to the right cause the clubface was closed to the swing line.

I guess, sometimes the measurement is not correct and It over reacts to sidespin/ Spin Axis imho.

[goatbarn]

There is a +/- on azimuth of 2* for the Skytrak. Also, path has a good amount of impact on azimuth, depending on the club....path has up to 30% influence.

[jrz]

ironFrank, I'm starting to see this more and more myself. Even when the ball hits the dent in my screen from the previous shot that went straight it will sometimes show the ball going 30 degrees left or right. It's not common, but it does happen enough to make me wonder if I am crazy or not.

I'm fine if these are just misreads, but I wonder if they would qualify for a rewind in a tournament round?

[doublebogey]

ironFrank, I've experienced similar to what you experienced above as well. However, interestingly, whenever I try to replicate on SkyTrak app, shot goes where it's supposed to go. It therefore seems like above usually only happens in sim play, so am wondering if it might be a small bug in the SDK somewhere that's causing this?

[SkyTrak_Seth]

It's it's 30 degrees for a IRL straight shot, then it's definitely grabbed onto the hosel or white-headed driver head. Try moving the ball back (to the right) an inch or so and see if that eliminates it.

[doublebogey]

Ah SkyTrak_Seth, that may be the answer! I've been having these straight chips or pitches or soft high flop shots showing up as 15-20 degrees left side angle, probably because I needed to place the ball a little bit IN FRONT (so to the left) of the laser to try to capture these high flops but the side effect is it might be grabbing onto the hosel thus messing up my side angles. Thanks for this insight.

[ironFrank]

doublebogey , jrz

Yesterday I tested a bit with that issue. I had, with an iron 6, a miss by 26 meters to the right on 150 meters distance, starting straight and then turning right. I am not able to produce such a shot even if I try to IRL.

- When you hit it more or less ok, and the spin axis is lower than 5 deg the shot will be as expected
- When you hit it with a more open or closed clubface and the axis gets to over 10 the trajectory gets extreme to one side

I've tested that and put the data into the flight scope shot optimizer and the curves werent that extreme at all

I guess the calculation is overreacting:

- My feeling is that the spin is not going to be reduced enough during the flight and it keeps the full spin up to the end, what is not possible IRL

[jrz]

I think you're now talking about a separate issue. There has been a long running discussion about the seeming exaggeration of the side spin in TGC. This was apparently updated about a year ago, but I still wonder how accurately TGC renders draws and hooks.

Just to be clear to ProTee, I think the new issue that needs to be looked into is when the ball veers off to the right or left in TGC even though it is hitting the same exact spot on the impact screen. There seems to be an intermittent error when calculating horizontal launch direction.

[ironFrank]

jrz

perhaps for TGC but the trajectory in the skytrak app, which I am using for training shapes, is still overreacting. On that way, I am not able to train a proper fade or draw, or a flat punch draw and can be sure, that I hit it right.

Yesterday we had luckily great weather in Germany and I did play 18 holes. There was only one shot really slicing cause I did fall back in downswing and the clubdace was open. But still on 200 yards it was only about 15 meters off the line.

So... the good thing is, that I feel, that skytrak helped my shots getting crisper and more accurate and I do benefit from the system. The bad thing is, that I sometimes may feel the urge to correct my swing, even if there is no reason for, cause I get (sometimes) a really bad trajecory even if I hit it only a bit wrong.

[SkyTrak_Seth]

Can you post a screenshot of a shot that illustrates what you're seeing? Would love to see the data and your guess as to what it would have done IRL.

[jrz]

jrz
So... the good thing is, that I feel, that skytrak helped my shots getting crisper and more accurate and I do benefit from the system. The bad thing is, that I sometimes may feel the urge to correct my swing, even if there is no reason for, cause I get (sometimes) a really bad trajecory even if I hit it only a bit wrong.

Very good point, sir. I feel the same way sometimes.