GPS vs. Laser

[phil75070]

[quote name='The Hawkeye' date='04 March 2010 - 03:44 PM' timestamp='1267739056' post='2293360'] I tried the iPhone app and that was a complete waste of time as I am a low handicapper and being 10-15 yards off, as it often was, rendered it useless for my game.
[/quote]

Many claim to be getting accuracy to 1-2 yards with iPhone apps, which is surely possibe as even a blind squirrel finds and acorn ocasionally. LOL

Actually, if the rumors about the chipset used in the 3GS are true, it [b][i]is [/i][/b]more accurate than what is used in the 3G. However, it is still A-GPS technology and it is doubtful that it would provide the consistent accuracy that a dedicated, WAAS enabled golf GPS provides. There are all sorts of complaints out there about the iPhone 3GS' (intermittent perhaps?) lack of accuracy, placing people blocks and sometimes miles away from their actual locations.

If one thinks about it, a SmartPhone is a multi-function device, a phone, MP3 player, as well as a GPS, while a dedicated golf GPS device is designed and built to do one thing. I would put more faith in the accuracy of a dedicated device, personally.

[TML]

[quote name='phil75070' date='05 March 2010 - 05:23 AM' timestamp='1267795412' post='2294544']
[quote name='The Hawkeye' date='04 March 2010 - 03:44 PM' timestamp='1267739056' post='2293360'] I tried the iPhone app and that was a complete waste of time as I am a low handicapper and being 10-15 yards off, as it often was, rendered it useless for my game.
[/quote]

Many claim to be getting accuracy to 1-2 yards with iPhone apps, which is surely possibe as even a blind squirrel finds and acorn ocasionally. LOL

Actually, if the rumors about the chipset used in the 3GS are true, it [b][i]is [/i][/b]more accurate than what is used in the 3G. However, it is still A-GPS technology and it is doubtful that it would provide the consistent accuracy that a dedicated, WAAS enabled golf GPS provides. There are all sorts of complaints out there about the iPhone 3GS' (intermittent perhaps?) lack of accuracy, placing people blocks and sometimes miles away from their actual locations.

If one thinks about it, a SmartPhone is a multi-function device, a phone, MP3 player, as well as a GPS, while a dedicated golf GPS device is designed and built to do one thing. I would put more faith in the accuracy of a dedicated device, personally.
[/quote]
You can put your faith anywhere you want. But I just played a round where my 3 partners all had bushnells. I had the Leupold and Iphone Golfshot. Since my cart partner was lasering every distance anyway, I pulled out my iphone (3GS) and it was accurate within a few yards. You can discuss theory until the cows come home. I am giving you an actual lab test result. Like I said, I'm not getting rid of my Leupold, but I'm also not going to spend $300 for a GPS over the $30 Golfshot.

[KevCarter]

[quote name='TML' date='05 March 2010 - 10:39 AM' timestamp='1267807175' post='2294911']
You can put your faith anywhere you want. But I just played a round where my 3 partners all had bushnells. I had the Leupold and Iphone Golfshot. Since my cart partner was lasering every distance anyway, I pulled out my iphone (3GS) and it was accurate within a few yards. You can discuss theory until the cows come home. I am giving you an actual lab test result. Like I said, I'm not getting rid of my Leupold, but I'm also not going to spend $300 for a GPS over the $30 Golfshot.
[/quote]

TML,

I am starting to feel guilty using you guys as lab test dummies.

I have used a laser for several years, the pinseeker, and while it's excellent, as I get older its harder and harder to hit the pin. I've been debating going with GPS, and I'm getting an iPhone for teaching anyway. It looks to me as though the GolfShot app is going to be a great way for me to go.

I really appreciate you guys taking the time in sharing your experiences!

Kevin

[golf_fanatik]

Another user of Leupold and Golfshot here.. My experience with the golfshot accuracy has not been as positive as TML's.

In my experience (I have the 3G), the gps function in the iphone is not accurate enough for golf and in the 20 or so times I have used it in rounds the info provided hasn't been close to the yardages provided by the Leupold or sprinkler heads..

I tend to agree with Phil that dedicated golf gps units are more accurate than iphone apps. I have used skycaddies, G5, upro, golf buddy and the golf guru. The most accurate have been the SG5, guru and original upro.

[KevCarter]

[quote name='golf_fanatik' date='05 March 2010 - 11:23 AM' timestamp='1267809795' post='2295004']
Another user of Leupold and Golfshot here.. My experience with the golfshot accuracy has not been as positive as TML's.

In my experience (I have the 3G), the gps function in the iphone is not accurate enough for golf and in the 20 or so times I have used it in rounds the info provided hasn't been close to the yardages provided by the Leupold or sprinkler heads..

I tend to agree with Phil that dedicated golf gps units are more accurate than iphone apps. I have used skycaddies, G5, upro, golf buddy and the golf guru. The most accurate have been the SG5, guru and original upro.
[/quote]

Sounds like the iPhone 3GS may have improved performance?

I think I will end up starting with the 3GS and GolfShot, do comparisons with my laser, and if it doesn't work out I will look into the dedicated GPS unit. The low cost of GolfShot makes for a pretty reasonable experiment...

Thanks for the info!

Kevin

[TML]

Kev,
the one thing you should know is that golfshot will use up a lot of iPhone battery. Follow the instructions on conserving power, turn off wireless, bluetooth, updates, and lock golfshot via the application and not the phone (keeps the gps on at all times). You will find that by the time the round ends, you have enough juice for a phone call. I am looking at getting a battery extender currently. I think you will be happy with it as long as you get the newer 3GS model.

[KevCarter]

[quote name='TML' date='05 March 2010 - 12:59 PM' timestamp='1267815590' post='2295198']
Kev,
the one thing you should know is that golfshot will use up a lot of iPhone battery. Follow the instructions on conserving power, turn off wireless, bluetooth, updates, and lock golfshot via the application and not the phone (keeps the gps on at all times). You will find that by the time the round ends, you have enough juice for a phone call. I am looking at getting a battery extender currently. I think you will be happy with it as long as you get the newer 3GS model.
[/quote]

Thanks again TML. I really appreciate your ideas! Knowing me, if its a slow round of golf, I will be spending a lot of time cruising this forum, I better have 2 battery extenders!!!

Kevin

[JofZ]

[quote name='phil75070' date='05 March 2010 - 08:23 AM' timestamp='1267795412' post='2294544']
[quote name='The Hawkeye' date='04 March 2010 - 03:44 PM' timestamp='1267739056' post='2293360'] I tried the iPhone app and that was a complete waste of time as I am a low handicapper and being 10-15 yards off, as it often was, rendered it useless for my game.
[/quote]

Many claim to be getting accuracy to 1-2 yards with iPhone apps, which is surely possibe as even a blind squirrel finds and acorn ocasionally. LOL

Actually, if the rumors about the chipset used in the 3GS are true, it [b][i]is [/i][/b]more accurate than what is used in the 3G. However, it is still A-GPS technology and it is doubtful that it would provide the consistent accuracy that a dedicated, WAAS enabled golf GPS provides. There are all sorts of complaints out there about the iPhone 3GS' (intermittent perhaps?) lack of accuracy, placing people blocks and sometimes miles away from their actual locations.

If one thinks about it, a SmartPhone is a multi-function device, a phone, MP3 player, as well as a GPS, while a dedicated golf GPS device is designed and built to do one thing. I would put more faith in the accuracy of a dedicated device, personally.
[/quote]

Phil, you seem to be 1 of 2 guys involved in this thread that actually has the knowledge base to back up anything he is saying. Thank you for sharing. Can you speak about civilian GPS and the common interference we see as consumers?

I am curious what you feel is the true MofE with handheld WAAS base GPS, since there is published data that goes against the brand name X marketing data being spewed all over the internet.

I am talking specifically about atmospheric errors, multipath effects, ephemeris and atomic clock errors, GDOP, natural radio signal interference, and artificial source interference like tv antenna malfunctions.

Would you also mind talking about military GPS sats and how they differ from what we all use to get directions on our smartphones and car navs.

I find it interesting you point out the smartphone apps, they are a complete waste of time.

TIA

[DaveLeeNC]

[quote name='TML' date='05 March 2010 - 11:39 AM' timestamp='1267807175' post='2294911']
[quote name='phil75070' date='05 March 2010 - 05:23 AM' timestamp='1267795412' post='2294544']
[quote name='The Hawkeye' date='04 March 2010 - 03:44 PM' timestamp='1267739056' post='2293360'] I tried the iPhone app and that was a complete waste of time as I am a low handicapper and being 10-15 yards off, as it often was, rendered it useless for my game.
[/quote]

Many claim to be getting accuracy to 1-2 yards with iPhone apps, which is surely possibe as even a blind squirrel finds and acorn ocasionally. LOL

Actually, if the rumors about the chipset used in the 3GS are true, it [b][i]is [/i][/b]more accurate than what is used in the 3G. However, it is still A-GPS technology and it is doubtful that it would provide the consistent accuracy that a dedicated, WAAS enabled golf GPS provides. There are all sorts of complaints out there about the iPhone 3GS' (intermittent perhaps?) lack of accuracy, placing people blocks and sometimes miles away from their actual locations.

If one thinks about it, a SmartPhone is a multi-function device, a phone, MP3 player, as well as a GPS, while a dedicated golf GPS device is designed and built to do one thing. I would put more faith in the accuracy of a dedicated device, personally.
[/quote]
You can put your faith anywhere you want. But I just played a round where my 3 partners all had bushnells. I had the Leupold and Iphone Golfshot. Since my cart partner was lasering every distance anyway, I pulled out my iphone (3GS) and it was accurate within a few yards. You can discuss theory until the cows come home. I am giving you an actual lab test result. Like I said, I'm not getting rid of my Leupold, but I'm also not going to spend $300 for a GPS over the $30 Golfshot.
[/quote]

If you think that you have really done "a test" you are fooling yourself. GPS is often good to a couple yards, and (less often) not accurate to a couple of yards. Do that same test a large number of times and you have demonstrated something (although you really need to carefully consider exactly how you are correlating a GPS measurement with a laser measurement - this is not simple. In fact for the average guy on the street it is damn near impossible).

dave

[JofZ]

I tried the iPhone app and that was a complete waste of time as I am a low handicapper and being 10-15 yards off, as it often was, rendered it useless for my game.

 

Many claim to be getting accuracy to 1-2 yards with iPhone apps, which is surely possibe as even a blind squirrel finds and acorn ocasionally. LOL

 

Actually, if the rumors about the chipset used in the 3GS are true, it is more accurate than what is used in the 3G. However, it is still A-GPS technology and it is doubtful that it would provide the consistent accuracy that a dedicated, WAAS enabled golf GPS provides. There are all sorts of complaints out there about the iPhone 3GS' (intermittent perhaps?) lack of accuracy, placing people blocks and sometimes miles away from their actual locations.

 

If one thinks about it, a SmartPhone is a multi-function device, a phone, MP3 player, as well as a GPS, while a dedicated golf GPS device is designed and built to do one thing. I would put more faith in the accuracy of a dedicated device, personally.

You can put your faith anywhere you want. But I just played a round where my 3 partners all had bushnells. I had the Leupold and Iphone Golfshot. Since my cart partner was lasering every distance anyway, I pulled out my iphone (3GS) and it was accurate within a few yards. You can discuss theory until the cows come home. I am giving you an actual lab test result. Like I said, I'm not getting rid of my Leupold, but I'm also not going to spend $300 for a GPS over the $30 Golfshot.

 

If you think that you have really done "a test" you are fooling yourself. GPS is often good to a couple yards, and (less often) not accurate to a couple of yards. Do that same test a large number of times and you have demonstrated something (although you really need to carefully consider exactly how you are correlating a GPS measurement with a laser measurement - this is not simple. In fact for the average guy on the street it is damn near impossible).

 

dave

 

Dave you are the 2nd

 

I just don't think the mass consumer cares, nor will he/she ever do the research. We have to remember the primary target audience for these units. First, GPS apps are cheap (you get what you pay for, often a glamorized score card). Second, any hand held GPS buyer is looking at them because they A) can not use a laser B) do not walk C) believe the hype in marketing D) all of the above

 

Some of the 22M buyers, purchased a unit to see what it would do in the real world. I put these people in the "other" category. Most carry some other form of yardage device (range finder) or yardage book, or they use a real caddie.

 

Any caddie that is passionate about his job will walk a course and provide the best information possible, again none of which a GPS can provide. The shorter the distance the more the MofE. A GPS will never contain yardage book information, you'll only know breaks and nuances if you have played before and then only if you wrote them down. If you are counting on a GPS from lets say a 125 yard shot, you move the cross hairs and believe you are within 99% of the pin, you will still have a 16 foot MofE. That is at its best. 5 yards is 5 yards and lets say based on my experiments 8 yards was the best I was able to get from unit to unit.

 

8 yards could be a club in some circumstances!

[phil75070]

[quote name='JofZ' date='05 March 2010 - 03:15 PM' timestamp='1267823719' post='2295464']
[quote name='phil75070' date='05 March 2010 - 08:23 AM' timestamp='1267795412' post='2294544']
[quote name='The Hawkeye' date='04 March 2010 - 03:44 PM' timestamp='1267739056' post='2293360'] I tried the iPhone app and that was a complete waste of time as I am a low handicapper and being 10-15 yards off, as it often was, rendered it useless for my game.
[/quote]

Many claim to be getting accuracy to 1-2 yards with iPhone apps, which is surely possibe as even a blind squirrel finds and acorn ocasionally. LOL

Actually, if the rumors about the chipset used in the 3GS are true, it [b][i]is [/i][/b]more accurate than what is used in the 3G. However, it is still A-GPS technology and it is doubtful that it would provide the consistent accuracy that a dedicated, WAAS enabled golf GPS provides. There are all sorts of complaints out there about the iPhone 3GS' (intermittent perhaps?) lack of accuracy, placing people blocks and sometimes miles away from their actual locations.

If one thinks about it, a SmartPhone is a multi-function device, a phone, MP3 player, as well as a GPS, while a dedicated golf GPS device is designed and built to do one thing. I would put more faith in the accuracy of a dedicated device, personally.
[/quote]

Phil, you seem to be 1 of 2 guys involved in this thread that actually has the knowledge base to back up anything he is saying. Thank you for sharing. Can you speak about civilian GPS and the common interference we see as consumers?

I am curious what you feel is the true MofE with handheld WAAS base GPS, since there is published data that goes against the brand name X marketing data being spewed all over the internet.

I am talking specifically about atmospheric errors, multipath effects, ephemeris and atomic clock errors, GDOP, natural radio signal interference, and artificial source interference like tv antenna malfunctions.

Would you also mind talking about military GPS sats and how they differ from what we all use to get directions on our smartphones and car navs.

I find it interesting you point out the smartphone apps, they are a complete waste of time.

TIA
[/quote]

There is no difference between "military GPS" and civilian GPS anymore. When GPS was first introduced error, known as "Selective Availability" (SA) was inserted on the civilian frquency, a non-encrypted signal, while the military and other authorized users had acces to the encrypted and accurate signal. However, since the error was not random but relatively constant, it could be determined what that offset was and it could be corrected for to a large degree. Since it was not achieving the purpose intended, and because of pressure from the civilian sector, by Executive order from Bill Clinton, SA was turned off in 2000.

All of the things you mention, atmospheric effects, multipath effects, ephemeris and atomic clock errors, GDOP, natural radio signal interference, and artificial source interference can introduce inaccuracies. However, there are ways to determine what the amount of error is for all but the last two you mention. There is no way to correct for the unknown, such as any interference caused by tall buildings nearby, trees or other radios/GPS devices close by. For the known and measurable errors that exist, such as atmospheric effects, atomic clock errors, etc., if the receiver and the error correction software is sophisticated enough, accuracy to about 1cm can actually be achieved.

Trimble has GPS survey devices that can achieve this type of accuracy. Navigational and location based services don't need anywhere near that level of accuracy either. Standard, uncorrected GPS accuracy of up to about 15m is typically acceptable. For golf applications, that could be 2-3 club difference and be totally unacceptable. So, the better devices use more sophisticated hardware and software and they are also WAAS enabled. Although the spec for WAAS is 7M, the government tests and reports on the WAAS system on a monthly basis. For January 2010. the typical error with 95% confidence was between .7 and 1.6m for all stations except Honolulu (which wouldn't typically affect us in the continental US). With 99% confidence levels, the accuracy was between 2-3m. Also, keep in mind that horizontal accuracy is always better than vertical accuracy.

I am no expert on the technology but was directly involved in the semiconductor business for about 30 years and high tech devices and technologies are something that have always attracted my interest and study. GPS is something I have followed as a hobby for almost 10 years now. There is a lot of bad information regarding GPS out there on the internet, bad because it is outdated. It seems once something is out there it never gets taken down.

One of the best discussions of the technology and how errors are corrected can be found at:

http://www.u-blox.com/images/downloads/Product_Docs/GPS_Compendium%28GPS-X-02007%29.pdf

It is 174 pages of fascinating (for me) reading!

[takafam]

Interesting discussion. I have both in the bag & while I agree that laser is more accurate than GPS almost everytime I've compared my laser to the GPS the difference is usually +2 yards with the GPS. One thing I learned with the laser when I shot archery professionally was I sighted my equipment in with my laser and I never cared what anyone else said. Strangely the same conversations that take place on the teebox happened in archery, whenever I lasered the target someone would say what yardage do you have which I would tell them but it was almost always different from them. Even though my laser was off I didn't care because I sighted my bow in with it. I do the same thing with my GPS I determine my distances with my GPS and that is how I determine my club distances. My buddy has the exact same GPS and the distances are usually off by the same amounts but I always use my yardage not his.

Everyone seems to have an obsession with comparing how accurate they are, even when I play with complete strangers using a cart with the GPS with few exceptions at some point during the round they role up and say what yardage do you have and then tell me theirs follow by a typical - these things are worthless. At my home course from almost every 150 yard stake mine will say 153 and consistency is all I'm concerned with. There are days though when the thing has a mind of its own and I do not trust it. Out comes the range finder!

I did make sure to get a good chipset with WAAS and large number of satellites as that was my main concern for accuracy/consistency. I've started my own yardage book as I think this will be the best and I can write down all my problem spots and experience, this year will be my first attempt to use. One of my main reasons is due to battery failure which sucks during a club championship, I knew I should have charged that darn thing!

[JofZ]

[quote name='phil75070' date='06 March 2010 - 04:30 PM' timestamp='1267911024' post='2297148']
[quote name='JofZ' date='05 March 2010 - 03:15 PM' timestamp='1267823719' post='2295464']
[quote name='phil75070' date='05 March 2010 - 08:23 AM' timestamp='1267795412' post='2294544']
[quote name='The Hawkeye' date='04 March 2010 - 03:44 PM' timestamp='1267739056' post='2293360'] I tried the iPhone app and that was a complete waste of time as I am a low handicapper and being 10-15 yards off, as it often was, rendered it useless for my game.
[/quote]

Many claim to be getting accuracy to 1-2 yards with iPhone apps, which is surely possibe as even a blind squirrel finds and acorn ocasionally. LOL

Actually, if the rumors about the chipset used in the 3GS are true, it [b][i]is [/i][/b]more accurate than what is used in the 3G. However, it is still A-GPS technology and it is doubtful that it would provide the consistent accuracy that a dedicated, WAAS enabled golf GPS provides. There are all sorts of complaints out there about the iPhone 3GS' (intermittent perhaps?) lack of accuracy, placing people blocks and sometimes miles away from their actual locations.

If one thinks about it, a SmartPhone is a multi-function device, a phone, MP3 player, as well as a GPS, while a dedicated golf GPS device is designed and built to do one thing. I would put more faith in the accuracy of a dedicated device, personally.
[/quote]

Phil, you seem to be 1 of 2 guys involved in this thread that actually has the knowledge base to back up anything he is saying. Thank you for sharing. Can you speak about civilian GPS and the common interference we see as consumers?

I am curious what you feel is the true MofE with handheld WAAS base GPS, since there is published data that goes against the brand name X marketing data being spewed all over the internet.

I am talking specifically about atmospheric errors, multipath effects, ephemeris and atomic clock errors, GDOP, natural radio signal interference, and artificial source interference like tv antenna malfunctions.

Would you also mind talking about military GPS sats and how they differ from what we all use to get directions on our smartphones and car navs.

I find it interesting you point out the smartphone apps, they are a complete waste of time.

TIA
[/quote]

There is no difference between "military GPS" and civilian GPS anymore. When GPS was first introduced error, known as "Selective Availability" (SA) was inserted on the civilian frquency, a non-encrypted signal, while the military and other authorized users had acces to the encrypted and accurate signal. However, since the error was not random but relatively constant, it could be determined what that offset was and it could be corrected for to a large degree. Since it was not achieving the purpose intended, and because of pressure from the civilian sector, by Executive order from Bill Clinton, SA was turned off in 2000.

All of the things you mention, atmospheric effects, multipath effects, ephemeris and atomic clock errors, GDOP, natural radio signal interference, and artificial source interference can introduce inaccuracies. However, there are ways to determine what the amount of error is for all but the last two you mention. There is no way to correct for the unknown, such as any interference caused by tall buildings nearby, trees or other radios/GPS devices close by. For the known and measurable errors that exist, such as atmospheric effects, atomic clock errors, etc., if the receiver and the error correction software is sophisticated enough, accuracy to about 1cm can actually be achieved.

Trimble has GPS survey devices that can achieve this type of accuracy. Navigational and location based services don't need anywhere near that level of accuracy either. Standard, uncorrected GPS accuracy of up to about 15m is typically acceptable. For golf applications, that could be 2-3 club difference and be totally unacceptable. So, the better devices use more sophisticated hardware and software and they are also WAAS enabled. Although the spec for WAAS is 7M, the government tests and reports on the WAAS system on a monthly basis. For January 2010. the typical error with 95% confidence was between .7 and 1.6m for all stations except Honolulu (which wouldn't typically affect us in the continental US). With 99% confidence levels, the accuracy was between 2-3m. Also, keep in mind that horizontal accuracy is always better than vertical accuracy.

I am no expert on the technology but was directly involved in the semiconductor business for about 30 years and high tech devices and technologies are something that have always attracted my interest and study. GPS is something I have followed as a hobby for almost 10 years now. There is a lot of bad information regarding GPS out there on the internet, bad because it is outdated. It seems once something is out there it never gets taken down.

One of the best discussions of the technology and how errors are corrected can be found at:

[url="http://www.u-blox.com/images/downloads/Product_Docs/GPS_Compendium%28GPS-X-02007%29.pdf"]http://www.u-blox.co...-X-02007%29.pdf[/url]

It is 174 pages of fascinating (for me) reading!
[/quote]

Thank you Phil, so assuming all things are perfect your MofE would anywhere from 1-16 feet. If there was an error it could either delay the accuracy or provide a much larger MofE?

[phil75070]

"...so assuming all things are perfect your MofE would anywhere from 1-16 feet. If there was an error it could either delay the accuracy or provide a much larger MofE?"

16 feet is a little loose. I would put GPS accuracy for the majority of dedicated golf GPS devices that are WAAS enabled to be within 10 feet with 99% confidence based on currently published data. I think most amateurs can live with that for full shots. Even the less sophisticated devices should give a good reading in a couple to 5 seconds max based on what I have seen published by manufacturers.

Of course, all of this talk about how accurate the GPS device itself can be does not take into account the accuracy of the map or the fact that since you are not sighting on a specific point it is difficult to impossible to determine what exact point on the ground that a "waypoint" is actually referring to unless you can map those points yourself. Walking a course to map it as some manufacturers do will be a [i]little [/i]more accurate than using satellite images as satellite imagery resolution is currently restricted to a resolution of .41m or 1.3ft.

[TML]

the test was no more than saying out loud what my iphone app yardage was, and having someone else call out what their laser was measuring (including my own). This was done at 4 different golf courses over a 2 week time frame. It seems that you have your opinion on my findings without being there. That's cool. I will tell you I own Apple stock at $70/share.

[finalist]

[quote name='kevcarter ' date='05 March 2010 - 09:28 AM' timestamp='1267810129' post='2295015']
[quote name='golf_fanatik' date='05 March 2010 - 11:23 AM' timestamp='1267809795' post='2295004']
Another user of Leupold and Golfshot here.. My experience with the golfshot accuracy has not been as positive as TML's.

In my experience (I have the 3G), the gps function in the iphone is not accurate enough for golf and in the 20 or so times I have used it in rounds the info provided hasn't been close to the yardages provided by the Leupold or sprinkler heads..

I tend to agree with Phil that dedicated golf gps units are more accurate than iphone apps. I have used skycaddies, G5, upro, golf buddy and the golf guru. The most accurate have been the SG5, guru and original upro.
[/quote]

Sounds like the iPhone 3GS may have improved performance?

I think I will end up starting with the 3GS and GolfShot, do comparisons with my laser, and if it doesn't work out I will look into the dedicated GPS unit. The low cost of GolfShot makes for a pretty reasonable experiment...

Thanks for the info!

Kevin
[/quote]


Kevin,
If you can hold out until June Apple will be releasing a new iPhone (their product cycle timing, and leaks all but guarantee it). Better camera (5 mega pixel) and rumored to have a cheaper overall cost when factoring in monthly costs. The processor will be much faster also.

[KevCarter]

[quote name='finalist' date='07 March 2010 - 12:02 AM' timestamp='1267941750' post='2298581']
[quote name='kevcarter ' date='05 March 2010 - 09:28 AM' timestamp='1267810129' post='2295015']
[quote name='golf_fanatik' date='05 March 2010 - 11:23 AM' timestamp='1267809795' post='2295004']
Another user of Leupold and Golfshot here.. My experience with the golfshot accuracy has not been as positive as TML's.

In my experience (I have the 3G), the gps function in the iphone is not accurate enough for golf and in the 20 or so times I have used it in rounds the info provided hasn't been close to the yardages provided by the Leupold or sprinkler heads..

I tend to agree with Phil that dedicated golf gps units are more accurate than iphone apps. I have used skycaddies, G5, upro, golf buddy and the golf guru. The most accurate have been the SG5, guru and original upro.
[/quote]

Sounds like the iPhone 3GS may have improved performance?

I think I will end up starting with the 3GS and GolfShot, do comparisons with my laser, and if it doesn't work out I will look into the dedicated GPS unit. The low cost of GolfShot makes for a pretty reasonable experiment...

Thanks for the info!

Kevin
[/quote]


Kevin,
If you can hold out until June Apple will be releasing a new iPhone (their product cycle timing, and leaks all but guarantee it). Better camera (5 mega pixel) and rumored to have a cheaper overall cost when factoring in monthly costs. The processor will be much faster also.
[/quote]

Thanks Finalist, great information!

Kevin

[biscuity]

[quote name='TML' date='04 March 2010 - 11:55 AM' timestamp='1267732522' post='2293153']
want to add, that the golfshot app was within 1-2 yds of the laser measurement.....well within my threshold of flaws
[/quote]

I don't think GPS is that accurate. I have a laser and my buddies have a few different GPS units and smart phones. To really see the difference, write down their best GPS "guess" for each shot, then record the laser number. At the end of the round I see a lot more than 1-2 yard differences.

And no matter how accurate the GPS is, you're forced to guess where the pin is in relation to front/middle/back. That alone is going to vary 1-5 yards depending on the size of the green and how good of a view you have of the pin location. If the green is flat to your line of site and 40 yards from front to back, it's not uncommon to guess 5 yards off. With a laser you just point and shoot and you have the exact number without any guessing or calculating.

From over a year of golf with my laser it has only let me down a few times... on part of a round due to dense fog (GPS didn't work either), as well as maybe 10 shots where I couldn't get line-of-site. But my GPS buddies often say they can't get reception, forgot to charge, out of battery, forgot to download the course, or are just getting funning readings.

[takafam]

In most situations your laser will never be the same as a GPS because your distance is always to the flag and the GPS is to the middle of the green which of course is most likely different by your given yardages. This doesn't mean it isn't accurate, but in my experience with both the readings I get for front of green and back of green are a lot more accurate with the GPS than laser. Front of green and back of green are extremely important to me as well and the only time I wouldn't care is during a tournament when I get a sheet showing pin location and distance to front, back and center of green.

My point is only that GPS accuracy is to front center back and that flag location is a guess with MofE. Laser is more accurate to the flag but not to the front, center or back of the green as that is guess work with MofE. Agree with some of your findings though with on fog and battery. Down side of laser is flat courses as it is harder to get good readings from the laser.

[biscuity]

I suppose it comes down to whether you would rather:


1. Know the exact pin yardage and guess about the F/M/B

-or-

2. Know the F/M/B within +/- 3 yards and guess pin yardage


For my game it's more beneficial to know the exact pin yardage. Higher handicappers don't benefit as much from the accuracy.

One other thing that isn't discussed much as a benefit of lasers is the ability to use them to see what's ahead. They are basically telescopes. It's nice to have a 7X zoom to look at the green to see undulations, pin placement on multi level greens etc.

[Buddyjay]

[quote name='biscuity' date='07 March 2010 - 09:24 PM' timestamp='1268015059' post='2300532']

One other thing that isn't discussed much as a benefit of lasers is the ability to use them to see what's ahead. They are basically telescopes. It's nice to have a 7X zoom to look at the green to see undulations, pin placement on multi level greens etc.
[/quote]


That's a good point that I never thought of. I own a Sonocaddie V300 and am very happy with it for all the reasons that GPS's are known for, but I just ordered a Laser for the other reasons discussed.

I like the fact of using a Laser at the range and the courses I play, do NOT give out pin sheets or do they have pin locations marked (Colored flags, etc.). My eyes for distance perception are not that great and I can't tell you how many times I thought the pin was near the front of the green and it was more towards the back. So I'm hoping that the Laser will be able to help me to see the pin location a little better.

[King_Slender]

I finally bit the bullet and went with the uPro Go, but my preferend for GPS over a rangefinder is more due to convenience. I like walking/riding up to my ball, takign a second to check out the lie, checking the GPS for the yardage and then pulling the club.

What I don't want to do (as I've experienced with range finders in the past) is having to open up the case you keep it in, standing there and trying to pinpoint the flag, then double checking just to make sure I locked onto the right target. It just throws my rhythm off.

I know laser is the most accurate, but even being a high single-digit handicap (8.9 index) I am not at a point where a GPS, even if it happens to be off by 2-3 yards for some reason, is going to affect my game. I know what distance I hit my irons, but I'm not at the point where I pure a 7-iron which I think should go 155, it ends up 2-3 yards short and I blame the GPS.

[biscuity]

GPS is off 2-3 yards due to the limitations of the technology, then you need to guess the pin location in relation to the F/M/B GPS numbers and calculate the yardage.

The result is a variance of 0-10 yards from the true yardage. So sometimes a GPS is spot on, sometimes it's off by a full club. A mid to high handicapper won't usually have a problem with that level of accuracy.

The better you get, the more important it is to know the exact yardage. A laser gives you the exact yardage within a yard with no guessing or calculations. That's why tour caddies use lasers to make their yardage books.

[The Hawkeye]

You didn't read the early postings...the "GPS is off by a full club" meme has been debunked. The OP is buying a new GPS, not a used GPS from circa 2005.

[redlabel]

[quote name='biscuity' date='12 March 2010 - 01:42 AM' timestamp='1268379764' post='2310995']
GPS is off 2-3 yards due to the limitations of the technology, then you need to guess the pin location in relation to the F/M/B GPS numbers and calculate the yardage.

The result is a variance of 0-10 yards from the true yardage. So sometimes a GPS is spot on, sometimes it's off by a full club. A mid to high handicapper won't usually have a problem with that level of accuracy.

The better you get, the more important it is to know the exact yardage. A laser gives you the exact yardage within a yard with no guessing or calculations. That's why tour caddies use lasers to make their yardage books.
[/quote]

[b]Why do you guess at the pin location?[/b]

On the three courses I play most of my golf, there are only 3, 2, and 0 pin locations that I don't see when I drive into the course or as I'm playing the round. I carry a spare scorecard and mark the location as I play, then when I get to that hole I know where the pin is.

My buddy never does this but he always asks me where the pin is. When we are playing with other people he keeps asking me where the pin is and as I keep telling him. The question invariably comes from one of the other two people we've been paired up with, "how come I know where the pins are". This usually happens on about hole 5 and so I explain it.

When we drive in we drive right by hole 2 and see the pin. I drive to the practice chipping green at the end of the range and can see the pin for #1 there. From our practice putting green I can see the pins on 9, 18, and 7. As we play number one I can see the pins on 5 and 8, and when we played the par five #2 we walk by greens 3 and 4.

So on the front nine, hole 6 is the only pin I haven't been close enough to know where it is. As we tee off on 7 I note the locations for hole 12 and walking down the fairway we can see the pin on hole 11. Ten is another pin I haven't seen, but when playing 10 we walk by 14 so see that pin location. When teeing off on 11 I walk about 20 yards and can see where the pin is on 13. When playing 14 we walk along the par 3 fifteenth. Hole sixteen is in the corner along the river so don't know the exact location but we walk parallel to 17 and right by the pin. So there it is and so I always know the location of 15 of the 18 pins for every round we play.

This was taught to me early in my golf life, during a match play tournament, when an older gentleman was kicking my butt and knew where every pin was on the course we were playing. He explained this to me after I lost the match on hole 18 which had a blind approach to an uphill green. When we saw where the pin and balls were I said he was lucky to have hit it so close to the pin. He replied, "young fella, luck had nothing to do with it, we could see this pin from the practice putting green before we started, from the tee of hole 6, and walked by it again on the way to hole 10 after playing the front." Over a beer afterward he explained his method and I've used it ever since on every course I've played since.

[phil75070]

[quote name='biscuity' date='12 March 2010 - 01:42 AM' timestamp='1268379764' post='2310995']
GPS is off 2-3 yards due to the limitations of the technology.....
[/quote]

That is a widely spread misconception. Trimble is a highly respected name in survey equipment and they can provide handheld GPS devices that are accurate within inches, maybe even tighter. It is not a limitation of the GPS technology itself, but the willingness and ability to apply the solutions available in both hardware and software that provide that level of accuracy at a price reasonable enough for the typical golfer.

All of these companies making handheld GPS devices are in business to sell them. There seems to be a market range as far as acceptable pricing. Up to now, any golf GPS more accurate than 2-3 yards would be cost prohibitive and not have a big enough market. Don't be surprised if that doesn't change in the near future.

[biscuity]

[quote name='phil75070' date='12 March 2010 - 05:25 AM' timestamp='1268400327' post='2311154']
[quote name='biscuity' date='12 March 2010 - 01:42 AM' timestamp='1268379764' post='2310995']
GPS is off 2-3 yards due to the limitations of the technology.....
[/quote]

That is a widely spread misconception. Trimble is a highly respected name in survey equipment and they can provide handheld GPS devices that are accurate within inches, maybe even tighter. It is not a limitation of the GPS technology itself, but the willingness and ability to apply the solutions available in both hardware and software that provide that level of accuracy at a price reasonable enough for the typical golfer.

All of these companies making handheld GPS devices are in business to sell them. There seems to be a market range as far as acceptable pricing. Up to now, any golf GPS more accurate than 2-3 yards would be cost prohibitive and not have a big enough market. Don't be surprised if that doesn't change in the near future.
[/quote]

OK, I'll rephrase it:

Typcial GPS devices made for the golf industry are off by 2-3 yards due to the limitations of the technology available for sub-$1,000 devices. And the accuracy of GPS will most likely get better in the future while remaining at about the same price point.

But it still doesn't change the fact that current WAAS devices in ideal conditions are only accurate to within about 2-3 yards. [url="http://www.kowoma.de/en/gps/accuracy.htm"]http://www.kowoma.de/en/gps/accuracy.htm[/url]

And that's only to the F/M/B, not to the pin. Even if you can sneak a look at the pin location in advance, you still have to guess how many yards it is from F/M/B. That calculation is probably off by more than the GPS.

[The Hawkeye]

buscuity...unless you are playing in some wierd atmospheric conditions, none of what you just said holds up with new top flight GPS's. I have a laser, I checked my regularly when I got it. Never off more than a yard or two. That's 6 feet, not even the length of a flag stick. To be honest, I distrusted my laser WAY MORE than I have distrusted my GPS. Because on laser shots over 150 yards I couldn't tell if I was locked on to the pin or bush just behind the green. I would find myself checking sprinkler heads, it was time consuming and tedious. The GPS is just much better for anything outside 100 yards all things considered. And my laser doesn't track my stats...

[KevCarter]

buscuity...unless you are playing in some wierd atmospheric conditions, none of what you just said holds up with new top flight GPS's. I have a laser, I checked my regularly when I got it. Never off more than a yard or two. That's 6 feet, not even the length of a flag stick. To be honest, I distrusted my laser WAY MORE than I have distrusted my GPS. Because on laser shots over 150 yards I couldn't tell if I was locked on to the pin or bush just behind the green. I would find myself checking sprinkler heads, it was time consuming and tedious. The GPS is just much better for anything outside 100 yards all things considered. And my laser doesn't track my stats...

 

I really agree on trouble hitting the pin with my laser, and I have a very good one. Every year it gets tougher. I am very anxious to try GPS this year...

 

Kevin

[biscuity]

buscuity...unless you are playing in some wierd atmospheric conditions, none of what you just said holds up with new top flight GPS's. I have a laser, I checked my regularly when I got it. Never off more than a yard or two. That's 6 feet, not even the length of a flag stick. To be honest, I distrusted my laser WAY MORE than I have distrusted my GPS. Because on laser shots over 150 yards I couldn't tell if I was locked on to the pin or bush just behind the green. I would find myself checking sprinkler heads, it was time consuming and tedious. The GPS is just much better for anything outside 100 yards all things considered. And my laser doesn't track my stats...

 

I played yesterday on a course that had GPS built into the carts, the nice GPS with green view and the actual pin location. I compared it to my laser every hole. There were 5 pins that were off by more than your 1-2 yard claim. Two were off by 4 yards.

 

That's acceptible accuracy for me. However, I don't think anyone can get that level of accuracy to the pin on a handheld GPS that only gives you F/M/B.

 

Don't get me wrong, I think GPS is great for lots of people. I'm just saying my laser gives me the exact pin yardage quickly & easily, and my real world comparison indicates GPS is frequently off by more than 2-3 yards.

 

Kev, what brand/model laser do you use?