New FlightScope Mevo+ (MERGED)

[Tony B]

You can have a 5 degree right path and a 5 degree closed/left face, effectively zeroing out your horizontal launch... so HLA isn't a reliable parameter to estimate face angle.

[Golfrnut]

 

Path and face angle do not have equal influence on ball direction. Ball start direction primarily follows face angle, so to a point, you can get a relative idea of face angle at impact based on start direction.

[Tony B]

Theoretically I agree.. but this doesn't hold true in these examples... particularly shot #6.. Face is 4 degrees Left, Path is 4 degrees right... end result is a horizontal launch angle of 1 degree in the direction of path.. not face.

HLA shows the end result of the combined face and path angles, but doesn't appear to be a close estimate of either in my data...

For me, i'm trying to get more neutral.. not trying to zero out completely.. but if I could improve my face/path extremes to get them more like 1-2 degrees instead of 4-6 degrees, I can decrease my amount of curvature a bit.. so face/path measurement can be important to see depending on what you are working on... Ultimately my HLA is pretty neutral in these examples, but "how" I get the HLA close to zero is important... is it with a slightly closed face, or very close face...

[Golfrnut]

 

That's because you are reading it wrong ;)

Path is +4...face is 4 left of path(which means it's 0* to target line). If it were 50/50, ball would start 2* right. It doesn't, it's starts only 1* to the right.

Hence what I said before...face has biggest influence. ;)

P.S. The monitor won't get it wrong anyway as it calculates face angle from ball start angle. It's always going to calculate the same way.

 

 

[Tony B]

Thanks..

I understand what you are saying and agree face should typically dictate ball direction more than path...but then help me understand why if face angle is either 0 at impact, or left relative to path, how ball direction is starting right if it's supposed to primarily follow face? Face angle is either 0 to target, or -4 to path... never right.. and HLA is 1 degree right?

I could certainly be interpreting it wrong.. I'm by no means any type of expert, so appreciate the explanation... a few of these shots on here seem to have ball direction following path more than face angle.. so I am a bit confused.

 

[Golfrnut]

 

You need to leave the target line out of your thoughts. The face is a vector...the path is the other vector. Ball starts between the two vectors, but will favor the face angle somewhere between 70-85* (depending on club speed, which is why driver has bigger influence). As a visual picture, the ball will not split the difference of the two vectors, it will go out 15-30* from the face angle vector. Same for when we talk AoA vs loft. Loft has biggest impact and ball travels on the same vectors as the influence is the same.

[physasst]

FWIW, I have the SC300, and my coach has Trackman. We have compared the two in the past. They were remarkably similar with respect to distances, swing speed, ball speed, and smash factor. The only thing that was different was that the SC300 carry distance on my driver and 3W were similar to total distance on Trackman. Anything 5 iron and under however, seemed to be spot on. Spin was a mess and not accurate, and apex height was also off. However, LA was pretty similar to trackman.

Just my 0.02 cents on the SC300

 

[Daniel Eason]

I can imagine tracking ball and passing club is going to be easy with doppler, look to one of the SSR devices to see it is pretty primitive.

Secret sauce in how they trace other bits of information identified by radar during a shot is where I think these devices are differentiated.

Mevo range probably has inherited some of this from top range devices.

 

[ScottBGKY]

Par2Pro posted some videos of the Mevo+ running on TGC2019

 

[clevited]

The spin differences are quite shocking between mevo+ and gc2. Unless they fix it, I have completely lost interest in the mevo. I have heard taking the sticker off helps, but then mevo+ is just calculating spin then as far as I understand. I would imagine it is fixable, constant flyers with irons is a big no-no.

[games]

You mean you lost interest in the GC2. The MEVO+ spin numbers in the 7-iron comparison were consistently 4500-4900. The GC2 registered three of six 7-iron shots in the 3000s, with one at an absurdly low 3300.

Now, in Foresight's defense, Cory stated in the video that they didn't really set up the GC2 as carefully as the MEVO. Additionally, I don't know if they adjusted MEVO+ settings for sitting below the level of the impact area.

[Tony B]

I'm with @games on this one... those 3000 rpm values on quad were odd for a 7i of that speed... the best quote I read on this kind of stuff was from gunghogolf in another group - "it's hard to know what time it is when you have 2 clocks"

[3_Jack_Par]

I feel like there should be two threads for this device. One for people who are interested in using it for indoor simulation and one for people using it outdoors. I'm a little unclear about whether these issues people are concerned with are limitations due to the short distance hitting indoors, or if it is also problematic when it's tracking a ball hit outdoors.

[clevited]

My bad, I watch both the 7 iron and Wedge video, I thought one of the videos someone posted was the wedge. The wedge is terrible.

 

https://youtu.be/c7owlV5ZdfQEdit: Forgot we have embed tool in this forum.

[clevited]

In the sim world, GC2 has a long history of being very accurate and consistent. It or GCQ are pretty much the measuring sticks for indoor launch monitors as far as launch numbers are concerned. Radars have been known to have issues indoors for years but they are superior in a lot of ways when used outdoors.

 

Edit: Just to be clear, I want the Mevo+ to be great, especially at its price point, but GC2 is my measuring stick as far as accuracy is concerned. I am not concerned with Mevo+ flight algorithms I am concerned with its launch numbers being realistic. I don't expect it to be as good as GC2, but at this point from the reviews I have seen, it isn't even as good or capable as Skytrak at this point in time. This is my opinion of course.

[kalin150]

GC2 is a very good gadget for its time. Yes, it has a history as a consistent LM. However, how do you thing is proven that is accurate? How about “very accurate”? Especially when it is one-on-one with other device with no third reference!? A few more remarks, GC2 doesn’t measure the spin axis till (respectively side spin), it calculates it from the face plane angles (din loft, face..). Saying that, how accurate are all camera LMs (sittings approx. on 90 degree angle to the shot direction) measuring face angles (that has to be relative to the target line) in 3D space when from this position it is extremely difficult to estimate precisely the target line?

Look, both types of LMs - radars and camera based have their pros and cons. And It is up to everyone to decide to himself which way to go. Budget is a Big one here.

My opinion, when choosing for consumer LM (200$ - 2000$ range), not a commercial 25K one, CONSISTENCY is something to look for. If it reads consistently, even not that accurate compare to big LMs - TM, GCQuad, X3...(these are also not that accurate as you might think, but good enough for coaching), it is easy to adjust your readings and have a very good tool to practice and measure your progress.

I would say, if you know well you device, its limitations and flaws, it can be very useful for coaching too!

 

[clevited]

I sort of agree. Consistency is paramount, but it needs to go hand in hand with reasonable accuracy imo. I plan to play online competitive golf with my sim once I repurchase. I used to have a Skytrak but I got sick of waiting for ball speed fixes as well as promised updates. It is also a frustrating experience too often when doing sim golf. It isn't consistent enough or accurate enough with ball speed for instance and I also found it got shot shape completely backwards randomly with driver shots. It also was tough to putt with on sim. I want a consistent and reasonably accurate LM. I prefer a radar for its simplicity over photometric and for its use outdoors at the range. I am hoping Mevo+ can fill that space for me at that 2k price and be at least as accurate as Skytrak was most of the time, but do so much more consistently. I am also hoping they can manage to get the putting to be more accurate and sensitive. So far as it stands, it isn't up to my standards and that is ok. I am not going to buy anything just yet anyways. I am going to give Flightscope some time to tweak the Mevo+ and if they get it to a satisfactory state of accuracy, I will probably buy one. If not, well I will just have to continue to save for a used GC2.

[Krt22]

I can't speak for the mevo+, but in my case (Xi+), two stickers side by side improves spin reads more so than no sticker.

[clevited]

Buy one and test it for me. I would certainly trust your methodology and results vs someone selling them for a living.

[Krt22]

lol, honestly I am mildly tempted just because of the video overlay and mild sim abilities, just tough to justify given I already have the Xi+

[Stuart_G]

@kalin150 said However, how do you thing is proven that is accurate? How about “very accurate”? Especially when it is one-on-one with other device with no third reference!? A few more remarks, GC2 doesn’t measure the spin axis till (respectively side spin), it calculates it from the face plane angles (din loft, face..). Saying that, how accurate are all camera LMs (sittings approx. on 90 degree angle to the shot direction) measuring face angles (that has to be relative to the target line) in 3D space when from this position it is extremely difficult to estimate precisely the target line?
Actually, accuracy of GC2 (and Trackman) has been tested against a very high end 3rd party reference. The results were published in a scientific paper. The only downside to the test is that it didn't include spin axis, likely because it was outside the capability of the 3rd party device to validate. If you want I can provide more info to help you search for the paper when I get to work (I think I already mentioned it earlier in this thread).
Also, GC2 doesn't calculate spin axis from face angle and path. That's what the radar units do indoors, not the foresight units. GC2 can't even measure face angle or path or lie without HMT and dots on the club face.
Although I agree the 2d image processing to 3d space conversion certainly leaves some room for potential error. Fortunately the data doesn't support that error really being significant.

[Celeras]

You can only lead the horse to water my man.

[kalin150]

 

You are talking of this one! Look closely at the table for the accuracy! Yes, I’ve missed the fact in pr2pro clip the GC2 was without HMT, but it does’t exclude the fact that a photometric LM situated 90 degrees to shot direction , CANNOT measure the spin axis, it just cannot! It is a calculated (extrapolated) parameter, with a compromises in the entered data (spin measurement data)!

when I mentioned 3rd party reference, I was meaning Mevo+ and GC2 being validated for the same shots, not in general.

I’m often using a TM4 and even this one has some weird readings from time to time (you visually see the ball flight and you know the reading is bad). I compared the Mevo(the $500 one) to TM4 for some folks, and it went surprisingly good and consistent. With constant 2-3% difference in readings (on one side) for club head speed, launch and cary! When you know that it is pretty easy to get a good, reliable device that not cost you a kidney ?!

But I totally agree that for practicing and coaching purposes the tolerance of the errors are insignificant!

 

[Celeras]

I get the impression you are linking that image with the intention of indicating a lack of accuracy. If so, I would suggest YOU look at it a little more closely. The reference ranges are insane for research grade. FIFTY rpms? And Foresight is still within that parameter more then half of the time. That is fantastic.

Apologies if I misunderstood the purpose you linked the image.

[Stuart_G]

@kalin150 said: a photometric LM situated 90 degrees to shot direction , CANNOT measure the spin axis, it just cannot! 

Sure it can. And it's actually not really all that difficult. All you need to do is determine the center of rotation on the 2d circular shape of the ball in the image. That then can be mapped onto the known 3d shape and projected through the center to get the spin axis. And that's just one option. Another is to just track the arc of a single point as it moves on the surface of the ball. That 2d arc can be projected to a 3d arc on the sphere which can also be used to calculate the spin axis.

[kalin150]

??. Exactly Stuard_G - all the options you’ve mentioned are “calculated”, “processed”, “modeling” as you said and as I stated! Not measured! Measure is a direct action. It’s like you are using a protractor. But from this position it is impossible!

Try to measure(model) “accurate” the spin axis within the short window of vision (with less than 20K fps), when the ball shape is changing soooo dramatically! Try to determine “the 2nd circular shape”(watch a slo-mo video of ball shape change within the first foot) ! .... I emphasizing on ACCURATE. Obviously they find an algorithm that gives us a decent data with a relatively good consistency. That’s why Forsights are actually the best for a Launch Angle reading for example. But for a spin axis I’ll give an edge on TM because it’s tracking the ball much further in space and when the ball already regained its form.

Now further, how much FpS GC2 cameras shoot - “up to to 10k” “foresight” states! By itself it’s is interesting statement because this is exact spec. of the equipment. It can not be “up to”! Ok now, go a little deep and find what are the FpS (and decent res.) needed for a very accurate info? You’ll find, at least double especially for higher ball speed(but that would be a very, very expensive LM). This is for all the community which blessing the big and expensive LMs as a holy grail!..... I’m not advocating for TM!

To stop this endless spinoff... - these LMs are very good. I use them and I’m perfectly fine. The do their job and there is nothing better on the market yet. Are they 100% spot on with the data - No. And in a given conditions and on a single shot or few, they can actually read not better than a low class LM. My point is - know your tech. Know it’s the limitation. Know the ball flight - in depth. And if you are serious about your game, go for a full flight environment. In The indoor short flight setup, you always can expect some discrepancies, even with expensive ones. Good for gaming and fun, but for ambitious golfers - practice by observing full flight.

[kalin150]

No need to apology Celeras. That’s good we have a discussion. For the 50rpm you mentioned- the GC accuracy is only 54% of the time. It goes 97 for 150 rpm. It’s gonna take a lot to explain, but actually for the 3 % cases it Can show very awkward readings. Actually, when you have some of this inaccurate readings ( the 3 %), they didn’t say how off those are. They just say 150+, but could be 500, 1000... who knows.

But as a short example - let say on Driver shot GC reads 3000 rpm (one of those 3%) with exactly 150 rpm mistake(again - could be more) on the higher side(actual spin is 2850rpm). Now Mevo reads the same shot with 150 rpm mistake on the lower side( 2700 rpm). The difference of 300 rpm in driver can give a difference in the cary (with the same ball speed and launch). Now you assume that GC is correct (cause more expensive) and Mevo reading is overrated on the cary, it would be bias. But actually both LMs are equally wrong!

However, my point to put the picture was to share a prospective of the overall accuracy of the leading LMs. And not blindly follow every reading of those. Again you have know ball flight well and how its characteristics are influenced by the impact conditions(factors).

[kalin150]

[Stuart_G]

@kalin150 said all the options you’ve mentioned are “calculated”, “processed”, “modeling” as you said and as I stated!
If you want to look at it that way, everything every LM spits out is calculated, No exceptions. Even the basic velocities. From a doppler radar, velocities are calculated from a frequency shift measurement. Velocities on an image based are calculated by dividing a (also caclulated) distance by a time. The only thing actually measured from your perspective is: for radar signal strength, frequency, and time. The only thing the photometric units measure is light intensity and time. Even positions and distances are calculated. Actually, if you really want to nit-pick, on computers, even time is calculated from clock cycles.
But that's not the point and it never was. When you look at it like that, It means nothing and is pointless to say whether something is measured or calculated. Smash factor is a calculation yet any error doesn't come from the fact that it's a calculation. If there is any errors, it comes from the possible errors in the ball speed and club speed, not the calculation.
The point of my posts were only that
1) Your earlier statement that GC2 calculated it using club data was incorrect
and
2) your statement that it wasn't possible to determine spin axis from just looking at the images of the ball was incorrect.
and now,
3) that your understanding of how much it distorts and how long the ball stays distorted is not accurate, It really doesn't take that long to return to round.
http://youtu.be/bF7h_EJ9WcA
specifically this is the frame I'm referring to, or really one of them. There is actually one more even sooner that shows the same thing. This is from a high speed camera that's at a much slower frame rate but you can easily see that the ball's traveled maybe an inch or two and it's already back and round enough to evaluate the spin axis.

[img]https://s3.amazonaws.com/golfwrxforums/uploads/381/B2LXMMDI5I9K.png[/img]
or this one's even better. It may not be perfectly round but it doesn't have to be and it's clearly round enough for GC2 to do what it needs to do.
[img]https://s3.amazonaws.com/golfwrxforums/uploads/117/20RWX25B6YMF.png[/img]
and those are both PGA tour driver club head speeds.
@kalin150 said But for a spin axis I’ll give an edge on TM because it’s tracking the ball much further in space and when the ball already regained its form.
So would I, outdoors - although even then it's not trivial because the unit has to be able to distinguish how much of the curvature is coming from the ball flight and how much from wind.
But indoors GC2 is going to have a little bit of an edge since it's calculating it from the ball. The radar units that do calculate spin axis from the club data have problems adjusting for things it can't measure, like the center of mass of the club (it can only determine center of volume) that can have some effect on the spin axis.
The biggest point of contention is the ability to apply gear effect for the drivers/woods/hybrids. Some don't even try - although Trackman has been working on updating the algorithms for that (or already has). Not heard anything from Flightscope on if or how they account for it.

[kalin150]

Great videos Stuart_G.I was expecting this commercial ones. How many frames you’ve got for the 1-2 foot tracking window? Very few on all the cameras in the video. Do you think is reliable 10 frames? How many actually are? My point is that the entering data for calculating and measuring is very hard to attain with 10k FPS especially on high ball speeds. And that is proven from the study. The accuracy of the GC n research mode is only 54%. Good 97% in coaching mode, but still in those 3% nobody states how inaccurate it is, just 150+... could be 750 or more. And you don’t know that this 1-2 shots on which we make conclusions (in Par2Pro video) are not in this 3%. I do not discuss the algorithms. Yes I did a mistake on how GC2 gets the spin axis, but I my point was not to say that can not be measured from images, just ca not be very accurately consistent! Maybe I didn’t put the correct word sequence, but the point is not the ability, but the consistency and accuracy!

But thank you for the valuable info, I think it is useful for everybody!