The conditions in that building, on that day, with that setup and ball,etc, etc...will never be the same as the actual conditions outside on the course that you cannot control. Plus, on the course you are not "give myself a half hour away from wanting to cut someone's head off and stuff it in a bowling bag." Therefore, your entire demeanor and attitude is different. Just go out and have fun. Sounds like to me, from reading these comments, that your game is quite good, unless you make your living at, just go with it. Those numbers on the machine are just some computer geek's way of messing with you because they can't play very well...And why are the numbers different - because the computer geek's are different.
Why can't there be Launch Monitor standards ?
If I had his game the last place I would be is hitting a ball into a wall and trying to figure out how to fuck that all up with a different head-shaft combo, based on shit that even that computer doesn't know.
I'm not suggesting Ty is the Chuck Norris of golf.
But neither am I denying it.
Pissing my pants laughing right now Steve!
So I guess u guys would get a kick out of the fact that I Mark my golf balls " Bad Motherfucker" in sharpie.
I'm working tonite...
Must...resist...the GC2...
I think I drive myself nuts with my " am I leaving something on the table" view. Always thinking I can hit it farther and be accurate.
Same was at the gym...I'm 5-6" in heels and I use the 36" box for box jumps...but I've stacked 2 smaller boxes to get to 42"....why? Because I look at those boxes standing there and I get like a drug addict in front of a mountain of coke.
Now if I had that attitude where I work....there it's, screw that I'm outta here.
How many strokes are you going to take off your score by (theoretically) gaining 10 yards, even if you can do it without sacrificing accuracy?
0.5? 1.0? Is that worth $400 and the time and the stress? Keep in mind that it is entirely theoretical, too. If you're asking these questions you've ready got something that fits you pretty well. Your best case scenario stroke gain is probably 0.1-0.5/rd.
If you're not hitting every GIR from a reasonable lie, and making 90% of your 4-footers, quit spending money on drivers. Practice. Time better spent.
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Here's the deal with a GC2. I know because I own one and use it all the time in the winter.
First the basic unit measures only four things, ball speed, launch angle, azimuth, back spin and side spin.
It is important to understand it measures launch angle and azimuth relative to the direction, both vertical and horizontal, the wide angle lens camera is pointing. To this end the unit has a built in compensation for the unit not being level in all axis. There is a software routine to set the unit up which requires the unit to be perfectly level. It stores the offset values of the accelerometer so when the unit is not level it knows how to compensate. If this is not done the readings will be off.
If the above is done correctly then the unit takes between 7 and 12 pictures per shot (less for fast moving, more for slow moving). These pictures are used to DIRECTLY measure the things listed above by computing the distance, angles and in the case of azimuth size, between the selected pixels and/or size in the images selected.. There is no way to juice these readings PERIOD.
What can be done, if you are using the Foresight range or course simulation software, is a constant multiplier to the carry distance computed. This scaling factor does not in any way affect the actual measurements.
What ever club you specify includes a constant smash factor. It is something like 1.45 for woods and 1.36 for irons. The swing speed displayed in the software is simply the ball speed divided by this number. You can also screw around with the wind speed and direction to effect the carry, ball height during flight, rate of spin change etc.
As to accuracy the things measured are the most accurate in the launch monitor industry. Foresight publishes the accuracy specs of each unit as shipped right on the front page of their website. I would note the radar units do not.
In summary if you hit on a properly maintained unit the results will be the same day to day, club to club within you own reputability. I do it all the time. It is actually more repeatable then going to the range or on the course since you do not have to deal with the uncertain wind, temperature and elevation conditions indoors.
Some people are reported to have trouble repeating their course swing indoors. My experience, after having quite a few people hit on my system is that what they really have trouble with is their ability to know how far they are actually hitting the ball on the course. The indoors/outdoors thing usually goes away after hitting about 10 shots.
There is another add on unit made by Foresight called an HMT which actually MEASURES directly clubhead variables like swing speed, attack angle,etc. with industry leading accuracy. These units require you put a few stickers on the clubface. I have no experience with these units since i do not own one. People that have them seem to think they are the greatest thing since sliced bread. They do output an almost bewildering amount of numbers per shot. These are in addition to those provided by the basic unit.
Ron...I wish you would post more!
I don't know what LM they were using, but I pretty much caught the guys at my Golf Galaxy (before it closed) jacking up the elevation or temperature or something to bump up the distances. I took my numbers and put them into Tutelman's calculator and couldn't get anything close to their distances.
Every launch monitor I have ever used has indicated that I hit the ball significantly farther than I know I can.
I suspect you guys are looking at the total distance computed. None of the launch monitors do anything but take an educated guess about total distance since computing roll is impossible. All they do is look at the decent angle , ball speed and final spin calculation and take a guess at the roll based on what you input as the ground hardness. What you need to look at is the carry distance. This is easy to do on course with irons not so much with a driver . You usually cannot see exactly where the ball landed, the ground slope at the point of ball ground contact, have any accurate idea of the ground hardness or what the actual elevation change is from tee to landing spot.
As an example one of the courses I have on the simulator is Spyglass, which is kind of hilly and has a lot of side slope. With the same wind and ground hardness conditions my total drive distance can vary from 275 to 210 with the same launch angle, ball speed and spin depending on what hole i am playing. The carry distance is also a lot different uphill or downhill although I don't remember what the max differential is.
The carry distance is fairly easy to compute on level ground. A friend of mine who was an aero guy on high performance fighters says the computation involving a golf shot compared to aircraft computations is lightening bug to lighting.
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No shit Steve...Ron comes out of nowhere with the best info.
So Ron, what I get from u on any inaccuracy is not the software, ( Foresight or Ping N flight) but the unit itself being level?
How do u level it? The one we have, and the one at the store is constantly being moved. Is is as simple as putting a level on top of the unit.
We have the HMT but I never use it...can't be bothered putting the dots on the clubs. If I want to check my AOA which is about all I want to see on that , I'll use someone else's driver
Interesting.
First you have to have the leveling software. It's free from Foresight. You then level the GC2, using a decent level with the front stand extended. If you have the unit in a protective case it's the same. You then let the unit warm up for about 5 minutes (the software provides a countdown clock). The software then runs for a bit and you're done.
What you are actually doing is finding the accelerometer offsets so when the unit is not level the software can adjust the readings to the flight simulation/computational software correctly.
The offsets are a normal thing when accelerometers are designed and manufactured. The offsets can also drift with time so you may want to run the calibrations software every now and then. On my race cars we redid them about once every three races but in a race car they get shaken really hard all the time.
After you run the calibration then the unit does not need to be level as the accelerometers will output the actual tilt correction and the flight software will adjust accordingly.
If you think about it that is the only way you could ever use these units outdoors since all ranges have a designed in tilt to facilitate drainage along with whatever settling has gone on since construction.
I don't know how many degrees of not level the correction can accommodate but for any tilt found in golf it would be hard to find an accelerometer that couldn't output a correction.
Ron, is anything on the GC2 actually measured or is it all calculations. And if calculations, what are they based on?
Flightscope uses Doppler radar, the old vector took pictures of the ball...
I'm seeing that whether the unit is leveled or not u can adjust smash factor on the Ping N' flight software anyway. Today's numbers made more sense to me.
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A GC2 actually measures ball speed, launch angle, side and back spin an azimuth. The distance is a calculation based on well known forever golf ball ballistics. These calculations are not what is called closed form where you plug the measurements and then get a distance. The calculation is iterative over many small time steps each one of which recomputes the present speed, spin and height. When the height calculation matches the ground level you have touchdown and the carry distance..
It is easy to measure those things optically. For instance ball speed. Take a two pictures of the ball at known time spacing. Then use vison software to find the centroid of the two images. You know the time between images and the distance between the centroids, So speed equals distance/time,
The thing a GC2 has going for it over say a Vector Pro or Skytrak is the wide field camera it uses. It takes between 7 and 12 pictures per shot. I have no idea what criteria they use to select the images to use for measurement but this kind of thing is fairly common in the industrial imaging systems. It is my understanding that the camera they use goes for something north of a grand as opposed to something like a Skytrak whose cameras go for something like $35,
The accuracy for the things it measures is far and away better then any other type of launch monitor optical or radar. Accuracy is really important when using the results for golf course simulation,
I find it amazing that radar systems don't upfront publish their as shipped accuracy specs for anything other then ball carry outdoors. If any company tried to sell high dollar industrial measuring equipment to design engineers without an guaranteed accuracy spec they would be laughed out of the building.
In the golf industry I guess it's the sizzle not the steak.