Watch accuracy

[cantwells]

About GPS watch accuracy. Are the front/middle/back yardages preset? Maybe like on a clock face with 6 always being front and 12 always being the back of the green? Do those yardages change should I be coming in from the 4:00 angle with that becoming my "adjusted" front of green and 10:00 being the new back of green? Does that question make any sense? The reason I ask is I’m considering the watch purchase as I recently lost my rangefinder. Thanks!

[Stuart_G]

Depends on which model you use and what data they programmed into the db. Some just use a fixed points for front/middle/back while others have more detailed mapping of the green outline and can use different points based on the direction you are approaching the green from.

 

[phil75070]

More often than not, front and back are fixed points with the front being the point of the green closest to the tee, and the back being at the farthest point. They are not necessarily even in line with each other. Handheld GPS devices like what you can get from SkyGolf you can even move the pin around on the green to approximate its location and then the front and back are in a line from you through the flagstick as depicted. Like Stuart_G said, it depends. Best to ask the manufacturer if they even know as they are typically getting their maps from a 3rd party.

[Juan Fabuloso]

My impression is front, back and center are fixed waypoints that don't vary with your position.

Years ago I played while a course mapper was walking the course. Talked to him several times through the afternoon about the process. He started from the green and worked to the tee establishing LAT/LONG data. The course super gave him a general guide to the greens, but he said he started from what was the center 20% of the green as his reference point. From there he logged back and front. He then used the "center" to work back towards the tee to log 50, 100, 150, 200 and 225 yardages according to what his antenna indicated were the distances from the center. Hazards were logged on both sides if they crossed the fairway. Tee boxes were walked off and he used the halfway point as a data point. He told be that he just got those points to allow a GPS device to triangulate and calculate the distance.

All that said, my Garmin watch drops the Front and Back yardages when I'm on the edge of the green. I believe it only uses the logged waypoints when you select a course to play. I think there would be too many variables and a ton of data to be that "real position" accurate.

Phone based apps are different. The ones that use satellite images have waypoints mapped software. Some combine the physically logged waypoints with software calculations to give you more flexibility in times where the phone can't get a good GPS lock. A lot of these apps allow you to create your own point to point distances.

Personally, I use a watch and rangefinder. Watch for all general shots and rangefinder to determine carry distances and tucked pins. I think it's a better system. Rather than spend $400 on a do everything watch, a $150 watch and a $250 range finder give me the best tools for unfamiliar tracks.

John

 

[LeftyMatt24]

I use a Garmin Fenix 6x which is an everyday watch that has the Golf features from Garmin as well. I find it to be as accurate as my buddies with their laser scope. Typically once I look at the green I take the number between middle and back and play to the biggest part of the green. I have found good results doing this for my game.

[larrybud]

You can check yourself. Go stand 50 yards pin high left or right from a green and check the front/middle/back. Are they the same?

 

[phil75070]

It is my understanding that almost all course maps (excepting those from SkyGolf) have fixed waypoints for front middle and back. For a green that is angled left to right, for example, the "front" would be at the point closest to the tee which would be front left, while the "back" would be the farthest point from the tee, back right. SkyGolf allows you to move the location of the pin on the green and that gives you front middle and back from where you are on a line through the pin. It is also my belief that no multi-functional watch or even phone app can match the accuracy or a dedicated golf GPS device as t here just isn't enough physical room to add the necessary circuitry to increase accuracy as a multi-functional watch and a cell phone have other functionality built in. Plus, civilian GPS, without getting into devices that cost well over a thousand dollars, like those from say a Trimble, is only accurate to within 3-4 yards, 95% of the time.

[Stuart_G]

That's not correct. Many of the garmin watches contain data on the full outline of the green and will use that outline and the players location to adjust those 3 distances based on the angle of approach to the green. The first one I was aware of that did that was the Garmin Approach s3.

[phil75070]

Didn't know that as I've never used a golf watch. Thanks for the info! Do you think a watch is as accurate as a larger, handheld, dedicated GPS?

[Stuart_G]

I haven't seen any hard data but to the best of my knowledge, in general the accuracy of the GPS receiver is equivalent. And the accuracy of the course data is dependent on the source of that data, not on the unit using that data. Memory isn't really an issue any more on the watches either. So the main difference is going to be in the usability features - size of the display, number of buttons, battery life etc...

But it's really not the best idea to generalize, each product really needs to be evaluated based on it's own features. Not all watches are the same just as not all hand held units are the same.

[ThinkingPlus]

FYI - I usually only count on ~4 yards accuracy in the horizontal plane for GPS. Can you get better? Yes. Can it be worse? Yes. It depends on many factors such as device hardware implementation, software, course location, and weather. Also you will always have a few yards of error just due to the multiple pin locations for each front, middle, or back region on a green. I use a laser rangefinder because of both the total GPS error as well as the variability of the error. See link for lots of detail. GPS.gov: GPS Accuracy

[awtryau89]

Just got the Garmin S62 and it is very very accurate for my home course. I have not tried it at any other locations but I check it against hazards and tucked pins with my partners lasers and its amazing how accurate it is. It for sure uses different angles to green front middle back as I have tested that specifically.