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Skytrak alignment and misreads - BIG problem!! need help as close to giving up on it.

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  • Skytrak alignment and misreads - BIG problem!! need help as close to giving up on it.

    I've owed my skytrak for a few months and until this weekend only used it outdoors. I was getting a lot of shots not registering and most shots going 40-50 yards left. The only way I could get more sensible/expected results was to close my unit to the target by around 30 degrees. I contacted skytrak and arranged for the unit to be tested. It was tested indoors and I was told that there is no problem with the unit and it working perfectly. I was pleased with this and put my bad experience with it down to the fact I used it outdoors. Over the last 2 weeks,I have had a major structural change to my property, had an upstairs wall removed and ceiling raised so I now have plenty of space. I have a projector fixed to the ceiling, connected to a laptop and a big white hitting screen with surround. The setup is perfect but I'm so disappointed with my skytrak unit. I've spent hours on forums reading about ball placement etc and I've tried it all but in my new indoor setup, I'm still getting loads of misreads and those big ridiculous left shots. I've only tested it with 3 clubs so far, 52 degree, 6 iron and driver. 52 degree gives a lot of readings and realistic results with the unit setup properly, but the 6 iron, lots of misreads and all going way left, to fix this, I had to close the unit by around 30 degrees. Driver was picking up most shots way left unless I close unit to target. I have tested with light on and off with similar results. I'm close to giving up on this unit but still hoping I can get some more suggestions/help. I'm going to buy a proper heavy mat that doesn't move and maybe I need to do something with the lighting but I'd imagine that might help with the number of misreads but won't solve the problem with the unrealistic 50 yard left shot. I'm desperate for help as I'm close to accepting that the unit just isn't as good as the advert suggests.

  • #16
    ...and here's just a few pics of my setup, I've added some artificial grass since my initial post and got a new hitting mat too.

    Comment


    • #17
      As far as I know, side spin is not a calibration issue, it is what it is. Left side spin is caused by closed face to path or impact toe side of center or both. The next step is to figure out source of side spin. Not easy, but possible

      1. Spray face with foot spray to determine point of contact.
      2. Make a gate of sorts using sponges or similar to determine path.
      3 .Face can't be directly determined but can be deduced by comparing actual HLA with path

      If real HLA is straight, path is straight, and center impact, ST sidespin must be near zero.
      Last edited by Morini; 12-25-2018, 02:21 AM.

      Comment


      • #18
        Bad hooks are far easier than slices once you swing in to out. Check your arms crossover rotation. Just sayin....but maybe you're a six handicap and know exactly what you're doing. Merry Christmas!

        Comment


        • #19
          Just to add to what I posted earlier. Here is my understanding of how the ST algorithm calculates spin axis.

          1. Ball passes later curtain. The refracted light is used to determine when the ball passes the sensor.
          2 .An IR strobe fires twice, capturing two images of the ball.
          3 .Those images are transferred to your device.
          4. Your device processes the image to locate the two ball images.
          5. The algorithm flattens the balls into two 2d images.
          6. The common areas of two images are compared relative to center of ball and are used to determine degrees of rotation in backspin and sidespin direction.
          7. Since time difference between the two images is known, rotation is converted to respective rpm, which is then used to calculate spin axis.

          On a related note, the center of the ball images are compared to determine ball speed and VLA. The size difference between images is used to calculate HLA.

          I could be off on some of the details. The point is that if HLA is accurate, spin axis is accurate. You are in all likelihood hooking the ball. The ST algorithm does not account for the spin dropping over time and will exaggerate a bad hook.

          Comment


          • #20
            mine must need to be recalibrated... ST parallel to target line 20 yard "straight" shots show up 6 degrees to right with 100 to 200 of side spin in both directions. Does anyone know a tilt or lean formula to help this issue? Really don't feel like sending it in for repair....I use it to much lol.

            Comment


            • #21
              Originally posted by Morini View Post
              Just to add to what I posted earlier. Here is my understanding of how the ST algorithm calculates spin axis.

              1. Ball passes later curtain. The refracted light is used to determine when the ball passes the sensor.
              2 .An IR strobe fires twice, capturing two images of the ball.
              3 .Those images are transferred to your device.
              4. Your device processes the image to locate the two ball images.
              5. The algorithm flattens the balls into two 2d images.
              6. The common areas of two images are compared relative to center of ball and are used to determine degrees of rotation in backspin and sidespin direction.
              7. Since time difference between the two images is known, rotation is converted to respective rpm, which is then used to calculate spin axis.

              On a related note, the center of the ball images are compared to determine ball speed and VLA. The size difference between images is used to calculate HLA.

              I could be off on some of the details. The point is that if HLA is accurate, spin axis is accurate. You are in all likelihood hooking the ball. The ST algorithm does not account for the spin dropping over time and will exaggerate a bad hook.
              Thanks Morini, very grateful for your response as always, this is very informative and relevant and I will try some of your tips. I have to disagree with you that there is not an issue with skytrak. I do have a tendency to sometimes hit left on the course but we're talking 20 yards max and only sometimes. The skytrak is exaggerating this, turning 20 yard left into a 60 yard left and doing it consistently and I believe turning a relatively straight shot into a 20 yard left shot. If I hit a 7i on the course, I tend to hit the green or miss it left and usually not far off the green. On the skytrak, i'm hitting it sweet but nothing in going at my target of 150 to 160 yards, a crazy and exaggerated amount of spin is being calculated and sending the ball 40-60 yards left of my target. The only way I have found to combat this so far is to close my unit 30 degrees, watch the ball start out right and it bend back into my target. I agree my swing can be improved but the skytrak is making me look worse than what I am and I think you'd agree that having spent $2k on it, I shouldn't have to compromise on the setup to get it to give a more expected outcome. A problem I have with closing the unit say 30 degrees for a full 7i is that if I keep it closed 30 degrees for example for a 50 yard half wedge, the ball will start right, come in a bit but miss my target right. I would therefore have to constantly keep adjusting the amount it's closed to target for every club. I will keep experimenting and looking for answers but I'm really not confident I will get the unit performing like a GC2. Two of my mates have used it and I play with them on the course and know where they tend to hit the ball and they too are generating a lot of left spin and sending the ball out to the left.

              Comment


              • #22
                Dave,

                I’m a bit confused where you write that you align the SkyTrak between square and 10* closed. You should be aligning the SkyTrak very close to square, or exactly square. That’s the first thing.

                Secondly, I notice that the SkyTrak is located within a recess. I guess it is possible that the second photo might be obscured because of this. It would be worth moving the Skytrak out of the recess, to make sure this isn’t an issue.

                Once you’re happy that the side angle is close to being correct (by testing as previously advised), as you say the only things affecting the offline distance are side spin and the algorithm. The algorithm probably does over exaggerate the offline distance slightly, but by no more than say 3-4y on a 150y shot.

                Post some shot data so we can see what we’re dealing with. Really, the easiest way to test your SkyTrak is to hit balls in real life, and observe. Many / most amateurs aim right of target (without realising) and pull the ball back online, so if you’re in a controlled environment and aiming straight in your sim, your normal shot will be a pull. Obviously, just speculation.

                Skytrak in general is accurate, as verified by tens of thousands of users. It is possible, I suppose, that your unit isn’t, but really you need to test it against real flight. Otherwise, we’re just speculating.

                Dan

                Comment


                • #23
                  Originally posted by DannyMRICS View Post
                  Dave,

                  I’m a bit confused where you write that you align the SkyTrak between square and 10* closed. You should be aligning the SkyTrak very close to square, or exactly square. That’s the first thing.

                  Secondly, I notice that the SkyTrak is located within a recess. I guess it is possible that the second photo might be obscured because of this. It would be worth moving the Skytrak out of the recess, to make sure this isn’t an issue.

                  Once you’re happy that the side angle is close to being correct (by testing as previously advised), as you say the only things affecting the offline distance are side spin and the algorithm. The algorithm probably does over exaggerate the offline distance slightly, but by no more than say 3-4y on a 150y shot.

                  Post some shot data so we can see what we’re dealing with. Really, the easiest way to test your SkyTrak is to hit balls in real life, and observe. Many / most amateurs aim right of target (without realising) and pull the ball back online, so if you’re in a controlled environment and aiming straight in your sim, your normal shot will be a pull. Obviously, just speculation.

                  Skytrak in general is accurate, as verified by tens of thousands of users. It is possible, I suppose, that your unit isn’t, but really you need to test it against real flight. Otherwise, we’re just speculating.

                  Dan
                  Hi Dan, I followed Morini's advice and hit 20 yard straight shots with a 7i to get side angle close to 0 to determine how to align the unit and it was close to square to target. The MAJOR problem I have to somehow overcome is the crazy amount of left spin the ST is reading. I have always played with a slight fade and sometimes a slight pull. The straight pull is caused by the face and path being equal and minimal spin on the ball. When a ball curves violently, there has to be a big disparity between path and face. I am physically unable (and I don't want to be able) to generate so much side spin on the ball making the ball curve so much on the golf course. It's in the recess as it needs to be to hit driver, otherwise I'd be swinging too close to the left wall on follow through. This however, makes no difference to the spin generated as numbers are the same when I take it out of there. I'll post some pics up later for you to have a browse. I'll hit a few different clubs too. Thanks Dave

                  Comment


                  • sdavidow
                    sdavidow commented
                    Editing a comment
                    Oh Boy...this is interesting!
                    A few weeks on my ST and a week or 2 with TGC.
                    Seeing the same thing...hitting way more left than I think I am/was/should be.
                    I'm not good enough of a golfer to know what my ball should be doing (or did) just from the swing...WHICH IS WHY I BOUGHT A SIMULATOR!
                    So I really have to eyeball the alignment? I'm guessing I need to find my local rep and get him out to help me with it as it seems like there should be SOME sort of easy alignment process that doesn't rely on me hitting a ball.

                    I may take it out to the range and try to see how "accurate" my hitting is vs. the ST.
                    Anyway...glad I found this post.

                • #24
                  Originally posted by DannyMRICS View Post
                  Dave,

                  I’m a bit confused where you write that you align the SkyTrak between square and 10* closed. You should be aligning the SkyTrak very close to square, or exactly square. That’s the first thing.

                  Secondly, I notice that the SkyTrak is located within a recess. I guess it is possible that the second photo might be obscured because of this. It would be worth moving the Skytrak out of the recess, to make sure this isn’t an issue.

                  Once you’re happy that the side angle is close to being correct (by testing as previously advised), as you say the only things affecting the offline distance are side spin and the algorithm. The algorithm probably does over exaggerate the offline distance slightly, but by no more than say 3-4y on a 150y shot.

                  Post some shot data so we can see what we’re dealing with. Really, the easiest way to test your SkyTrak is to hit balls in real life, and observe. Many / most amateurs aim right of target (without realising) and pull the ball back online, so if you’re in a controlled environment and aiming straight in your sim, your normal shot will be a pull. Obviously, just speculation.

                  Skytrak in general is accurate, as verified by tens of thousands of users. It is possible, I suppose, that your unit isn’t, but really you need to test it against real flight. Otherwise, we’re just speculating.

                  Dan
                  Another frustrating session in which I experimented a bit but didn't really learn anything new. See pics attached:

                  Comment


                  • Gresh12
                    Gresh12 commented
                    Editing a comment
                    It may help us a bit if you select a club in Skytrak so we know what you are hitting. The spin seems all over the place (including backspin). You have one that launches at 24* with 90 mph ball speed and only 3400 rpms of back spin. I’m guessing that’s a wedge and my only thought on those numbers is it’s very fat causing the heel to stall and toe take over producing a huge hook. When I hit it fat on my mat I lose a ton of backspin and it’s often a big hook with the club flipping.

                    Can you produce big slices on purpose?

                    I can’t speak for your specific unit but mine has been to the range and also compared side-by-side with Trackman and shot shapes were very close on both comparisons.

                  • Jtangm04
                    Jtangm04 commented
                    Editing a comment
                    Have you had a friend come over who you know is a scratch golfer and give it a try? If there numbers look great, then it would reassure you it's not the tool but the user (like 90% of us here). Indoor swing really does affect a lot of golfers.
                    For me, I have a golf buddy who is a 4-5 HCP golfer and easily drives it 270-280 straight in real life, but on the simulator will typically hit 220 yrd hooks cause he tightens up on the backswing.

                • #25
                  Gresh12, you have focused on the only shot that was hit heavy. The others hit well, NOT heavy and the left spin is the area of concern. I hit wedges, 8i and rescue in the pics.

                  Comment


                  • Gresh12
                    Gresh12 commented
                    Editing a comment
                    Sorry I’m trying to help. The first shot could be a 7 iron or a driver based on launch angle and ball speed depending on your skill level. If it was a driver or 3-wood the backspin is in the ballpark but if it’s a 7 or 6 iron it looks to have the same issue as the shot I called out that I guessed was a wedge.

                    My typical 7 iron launches around 16* with low 120s ballspeed and about 6k backspin. When I catch it heavy the spin drops (granted it doesn’t drop in to the 3k range) and I can hook it as I described.

                    Try hitting irons off a low tee picking the ball clean to get the mat out of the equation with irons.

                    I will say I can easily produce the hooks your showing if I try to hit my hybrids in my 8 ft ceiling as I have to choke down to not hit ceiling height and I get tentative so super around. Like others have said the woods could be indoor swing for sure if you are at tight or not used to it.
                    Last edited by Gresh12; 12-27-2018, 01:44 AM.

                • #26
                  jtangm04 I do believe there's some truth in that. I am still getting used to swinging the club indoors and with the woods, I don't trust that I have plenty of space to swing and I hold back a little but this is not the case for my irons. I'm playing on the course tomorrow and will get some feedback to compare if there is a difference in my indoor and outdoor swing. I will get a pro to test it too as I'm not having much joy.

                  Comment


                  • wbond
                    wbond commented
                    Editing a comment
                    Have you taken it outdoors to test? If not, i would suggest trying that and use something other than a range ball but ones you don't mind donating.

                • #27
                  From a side angle perspective, it looks like you've solved the alignment issue. It looks like your issue now is due to a heavy amount of hook spin, and it looks pretty consistent...if that's not your normal shot shape, then the most likely source is the mat (grabbing the club face and closing it down). There's not really a way for just side spin to be a problem with the hardware. What do your driver numbers look like?

                  Comment


                  • #28
                    Well, it can only be one of two things, Either you create the side spin or the unit is faulty. Best to take it outside or. compare with Trackman to find out which it is.

                    If the unit does create false sidespin, I wonder what it would do for a lefty? Try placing the unit between you and the ball so you can "simulate" lefty shots while swinging right. If you now slice we know it is the unit. I may not be thinking straight due to all the turkey and other food I've gobbled down the last few days, but shouldnt miscalibration caused side spin be opposite if you swing opposite direction?
                    Last edited by Morini; 12-27-2018, 03:30 AM.

                    Comment


                    • #29
                      I'm back and not defeated yet, thanks all for your help. I didn't make it out to the course earlier as the weather wasn't great.

                      SkyTrak_Seth - see pic for how closed the unit is, not an issue for me if I don’t have to keep changing it for each club. Grateful for your feedback on the latest screenshots.

                      Gresh12 - my apologies, I do appreciate you are trying to help and I am grateful. I have just felt very disappointed so far with the ST and after spending thousands of pounds to get where I am now, however, I had a much more positive session earlier and not all shots going left with the high left spin. I do believe the unit is giving exaggerated left spin numbers but I realised I haven’t been following through as much as I would on the course and believe my hands were taking over a bit. I have attached more pics from the session earlier, a bit of a mixed bag but I believe more realistic.
                      I’m not a big hitter but the driver distances were lower than I’d expect. I hit Driver, 22 degree rescue, 5i and 8i and all with and without a tee. One 5i went 188 yards which is much further than I normally would hit with that club. What are your observations with the latest screenshots? Go nuts, I won’t be offended honest ;-).

                      Morini, I didn’t try your suggestion to see if placing unit between me and the ball will produce slice spin but will give this a try and will take it out to see where the ball is actually going. Again Morini, grateful if you have anything to add with the latest screenshots, any patterns, anything positive or negative?

                      Comment


                      • Gresh12
                        Gresh12 commented
                        Editing a comment
                        I’m looking at this on my phone so wasn’t easy to compare shots but here are my general observations:

                        - the drivers do look like a big hook visually which may not be your ball flight in practice but I will say the few I looked at were less than 35y left and I believe tour driving dispersion is about 70y so I’m wondering if the visual looks worse when you see the trail than you’re actually getting (the bigger misses are left rough not trees).
                        - you were able to produce a big slice so it’s not that everything hooks which I guess we can call a positive
                        - the no tee on average appeared to hook more than those off a tee for the irons. This still suggests to me you are catching turf and it’s shutting the face on you (there was one big hook off a tee also though but I’m wondering if that was still heavy. I have my unit on the axis view for spin so not as used to sidespin numbers vs degrees but if I put a big hook swing on an iron and catch the turf I can produce hooks like you are seeing. I’d try to hit 5 balls solid off a high tee where you pick them clean (delete shots you feel any turf) then hit 5 off the turf without a tee and compare.
                        - the hybrid and driver are longer clubs so are more prone to indoor swing so I wouldn’t rule this out. I’m guessing your flattening on these.
                        - your unit is still closed a lot in my opinion if your mat runs parallel to screen. If The unit needs to be angled that much so a centre shot reads straight I’d be concerned on calibration. Maybe Seth can comment before you send it for repairs but that angle looks too big to me. I don’t think this impacts your spin but raises general questions.
                        - I’m not a golf teacher but you seem to be adding loft to your 8 iron (launched one with 11k spin and another at 27* compared to normal of ~8k and ~18*) so I’m wondering if you’re flipping your wrists at impact to square the face and then the turf is exaggerating it.

                        Not sure I’m really helping at this stage but my general comments are: I don’t like how closed your unit is in general but the spin still feels like it could be mat/indoor swing.

                    • #30
                      That alignment is crazy looking, nevertheless, based on start direction and spins, looks alright! But, besides that, I notice the big hooks also have lower launch angles...I ain't no teacher, but seems to me you might be over rotating your arms or applying strong wrists and hands or something in a flatter swing that results in a ton of left spin. I also noticed that regardless of distance, if you released at the right side 100 yard marker, you'd be hitting the pin, looks likes every time!

                      Comment

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