Projector

[digger]

Doing my first simulator build. The room is 14 wide x just short of 10 high. Going 12x9. Want a good projector but the BenQ 935ST that I'd like to get is pretty spendy and the 936ST is even worse. Will I do those projectors justice on a 4:3 screen or would I be wasting money? Plan on running Mevo Plus with an I Pad at least to start with the courses that come with it. Can upgrade down the road as I see fit.

[COgolfengineer]

I have the LK936ST projector and only have a 10ft wide screen and project in 4:3. I am losing pixels on any projector so you still get benefits with a 4k projector. It looks great.

However, I think you're better off investing more in a better launch monitor and get a gaming PC rather than an expensive projector and you can upgrade that over time. Camera based launch monitors are much better indoors and almost all of them measure spin axis where a radar device like Mevo+ doesn't.

[preludesam]

It absolutely does measure spin axis. I measured mine vs my EyeXO and it was very consistent. It’s what pushed me to an X3 since I had the space to take advantage of radar indoors and full tracking at the range.

[COgolfengineer]

preludesam It does not measure spin axis of the ball. If using inddors and using a metal sticker or RCT balls, it can measure total spin of the ball. To get spin axis, radar uses the strike location and other ball parameters to calculate the spin axis and extract the back spin from total spin. If the strike is near center and the center of gravity of the club is at center, then the calculation can be quite good. However, once you get toe strikes or heal strikes, it suffers. And it's worse on the longer clubs since gear effect is more pronounced. And if you have movable weights on a driver and shift the CG away from center, spin axis will be off. But even if you get shots where the spin axis is close to a camera device that measures the spin of the ball, it's still a calculation and will be prone to more errors than a device that measures the spin axis of the ball. Outdoors, radar is great and still doesn't measure the spin axis since it can easily calculate it based on the entire ball flight.

[preludesam]

Is there any research you can site to support this? Quick google and Trackman does state indoors is calculated but outdoors is measured. Is this an issue with availability of revolutions to measure? Logically if you can measure the total spin could you not measure the direction of the spin or is this an impossibility?

[COgolfengineer]

preludesam I read a paper years ago but I can't remember the name of it. Outdoors, they only say the spin is measured because it can see the entire or at least enough of the ball flight to extract the spin and that calculation is pretty accurate. If it could actually measure the spin of the ball outdoors, then it could do it indoors. Adding the metallic sticker on the ball allows the radar to pick up the total spin but it can't detect the angle at which it's rotating, just a fundamental limitation of any radar LM. And most of the radar LMs added cameras so it could more accurately pick up impact location which is why they require a certain amount of light to pick up impact location and give you a better spin axis calculation. And you have to select the club you're using for it to calculate the spin more accurately. So with all those requirements and indoor vs outdoor requirements, they're basically telling you it can't measure spin axis, similar to how camera LMs can't measure the club data without reflective club stickers. But with proper lighting and accurate impact location, the calculation can be pretty good especially with shots at the center of the club. You might ask, why can't they measure spin axis with the camera they have on the radar LM? Maybe they can if the hardware was correct but they don't because if they could measure the spin axis of the ball with the camera, then they could certainly measure backspin or total spin as well and then you wouldn't need RCT or metal stickers, but you do, so clearly they're not measuring any spin with the integrated camera.

The only thing that really matters is if you trust the data or not and if your ball flight patterns on well struck and bad hits match your patterns outside. There's always an element of faith in the data for an indoor LM. But I would never recommend a radar LM for indoor use.

[digger]

I am very new to this and want to make good choices without spending a fortune. I have never used a Mevo Plus but have read many positive reviews. The price is attractive, I have room for it and l I like that at least some software comes with it so that it can be used right out of the box. I also like that the monitor is behind so both right and left handed players can play together. I hate the idea of annual subscriptions. I want to use it indoors probably exclusively. The Mevo Plus seemed to check the most boxes but I might have missed something and am open to advice from more knowledgeable members.

[Bubba22]

Totally agree. Trackman uses OERT to better calculate spin axis by measuring strike point on the face. I hope Mevo plus does the same. Interesting MLM2Pro is using 2 cameras to measure spin axis with specially marked balls. It also has radar.

[COgolfengineer]

digger I have seen a lot of people start out with a Mevo+ and then upgrade to a camera LM later. Chipping and putting is a pain point for a lot of Mevo+ users. What's the size of your space?

There's some good options for a camera LM such as a used GC2, BLP, and Uneekor is coming out with the EyeMini in April. BLP has an annual subscription but it's a great value imo. The Basic sub is $250/yr which is about 3 rounds of real golf, at least in Colorado. If you want a good value and no sub, then a used GC2 is a good bet. Can find one for under $3k. They're built like tanks and many golf teaching pros still use them. Or wait for the EyeMini...$4500 and no sub.

The projectors you mentioned are on the more expensive side, so I would suggest a less expensive projector which there are many great options, and invest the savings in a more accurate LM. And if you have a floor unit that sits to the side, a lot of people move them for lefty/righty by having a dedicated spot or can even place on a lazy susan, so it's doable.

[preludesam]

I understand, it’s kind of puzzling that total spin is measured but not the direction of the spin. You would think if one is possible then both could be measured. Interesting none the less.