Golf GPS technology... need opinions

[SubPar]

The original and current "raw" GPS is only accurate to about 10 yards. Using sophisticated error correction and WAAS, golf GPS systems are generally accurate to 1-2 yards.

I originally had some problems at the range I go to, but have found there is trouble in the area with stable/strong satellite contact. On the courses, every time I have checked my iGolf against the laser range finder they always agree within 1-2 yards, if not exactly. I have read that courses with GPS on the carts usually have a fixed reference tower on the grounds which greatly improves performance.

I can use my range finder to spot the pin precisely on a large green, but in only three rounds I have come to find the green front and back yardages very useful. Once this weekend found myself in a position where I had to play down an adjacent fairway and then over trees which blocked my view of the flag. Knowing the green center number from the ball allowed me to correctly select a club that would both get me over the trees and onto the green. I am sure I would have under clubbed if I did not have that number within a couple of yards.

Having both GPS and laser is great.

SubPar

[iacas]

The original and current "raw" GPS is only accurate to about 10 yards. Using sophisticated error correction and WAAS, golf GPS systems are generally accurate to 1-2 yards.

I've heard that, uncorrected, it's accurate to within 3 meters or 10 FEET. So either you got some units wrong or I'm not remembering correctly.

I've had GPS for when I'm out traveling in my kayak, and there's no way I've ever been anywhere near 30 feet off. Normally it's spooky how accurate it is, and I could turn the error correction on and off on my model. It made little difference. Even still, I believe much more so in laser range finders than GPS.

[SubPar]

I've heard that, uncorrected, it's accurate to within 3 meters or 10 FEET. So either you got some units wrong or I'm not remembering correctly.

I got that number from

this piece. The writer says that without differential GPS the basic satellite only system is only accurate to 10 yards. Generally, it appears that without WAAS or some other fixed known reference point it won't be much more accurate than that. This is probably the best info on how GPS works . It is from Trimble who made the first GPS systems for boats back in the '80s. All things considered, the addition of the iGolf GPS to my bag will save me a stroke or two every weekend. Maybe more. SubPar

[wolverine318]

This is something I again did some experimenting with last Saturday as I am looking to get one or the other but want to make the best purchase obviously.

Im leaning towards a GPS but am doing everything I can to prove the device to be ineffective or otherwise "off" with its yardages.

I have not been able to do so yet. GPS and rangefinder yardages have been within a yard of each other on every test, +- either way.

For testing to the flag we had the rangefinder read the yardage and the gps we used the MARK feature. We also did this for drives where we used the mark and the rangefinder stayed behind and lasered us at the ball. The course was empty we went later at night as to not hold anyone up.

Course libraries and using the pc is not a problem for me, all the courses in my sat league are in the library but 2 new ones and Im on my pc all day so its no big deal to me to connect the device and change courses.

I see the benefits in both and cons in both. But yardage wise my findings have shown no dramatic differences as of yet.

[SubPar]

This is something I again did some experimenting with last Saturday as I am looking to get one or the other but want to make the best purchase obviously.

I see the benefits in both and cons in both. But yardage wise my findings have shown no dramatic differences as of yet.

I have found both to be useful and accurate so far. The GPS give dstances to things you can't see or get a fix on with the range finder. The range finder can provide distances to objects not mapped on the GPS (like a tree, the pin or ground under repair)

Course libraries and using the pc is not a problem for me, all the courses in my sat league are in the library but 2 new ones and Im on my pc all day so its no big deal to me to connect the device and change courses.

I am not sure how many courses I can store in my iGolf, but I have 13 in it now and room for at that many more, it appears.

SubPar

[MPS67]

Subpar,

I have read your posts where you're claiming that your igolf distances float after you stand at the ball for more than a brief moment. Is this still the case? Also, will this affect distances to other points such as water hazards and bunkers?

At times, I could see myself standing at my ball and unsure of my strategy. I might need an extra minute while contemplating my shot. How soon after you come to a stop does the igolf start to wander? Could you simply walk around in a 10ft circle to re-capture a precise location after it wanders?

Thanks in advance for you answers,

Mark :)

[SubPar]

The drifting problem I had seems to only have been at the range where I first used it. I did notice weak sattelite signals in that area as opposed to on the courses where they are pretty strong.

Since I have been using the iGolf on the course I have had no complaints. I tend to glance at the yardage when I arrive at my ball and then make my decisions. So far my iGolf agrees with yardage markers when I am near them and I figure the FCB numbers have been good based on experience. Virtually every time I happen to stop at a yardage marker on the fairway I find the iGolf within a yard or two of that center distance, if not spot on.

SubPar

[rrassoc]

I just found this review from GolfTest USA.

[SubPar]

I just found

I got my iGolf for $190 on e-bay (new) and am pleased with it.

Eight programmable points on each hole is a big plus. I mapped a course they did not have and I got 6 additional course downloads for the file. The AA rechargeable batteries last more then two rounds. You own the files when you download them and you can back-up the course info with your custom points. Not much to dislike about it. SubPar

[DaveLeeNC]

I owned an iGolf unit for a while. I ended up being a rangefinder type guy (exact yardages inside 100 yards is what is most important to me by far - gotta be laser for this). At the time that I did this I didn't have a rangefinder, but I did a fair amount of "accuracy work" and came to the conclusion that GPS is accurate to 3 yards 91% of the time and 5 yards 99% of the time.

The following link to another "board" describes what I did here.

http://tinyurl.com/2fudaf

I also ran into this "it doesn't work well when you stand still" problem. I still do not understand why this is the case, but it seems to be and it really doesn't matter once you know it. If laser technology ever became illegal, I'd probably go back to iGolf.

dave

[SubPar]

Getting the exact yardage to the pin is always a great option to have. I find any reasonable estimate of the distance to the front and back of the green to also be good to have, so I use the iGolf and rangefinder.

I have heard users of other GPS golf systems mention the drift issue and as I posted before somewhere, that is because the Earth and the satellites are moving/drifting constantly. Apparently it is easier for the system to do "error correction" when you are moving as well. Given the requirement for sophisticated error correction with GPS units where accuracy is a must, it is pretty amazing these little units can be as good as they are.

From what I have read, a higher degree of accuracy can be attained where there is a ground based reference point, and some golf courses actually have one on the grounds or nearby.

technical resource
SubPar