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GPS accuracy


amabejo

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I am currently using a Samsung Galaxy s3 as my GC device running Locus Map Pro. I seem to only be able to achieve an accuracy of about 5m (ie when I am at a predetermined point the compass says I still have about 5-7m to go). If I switch the gps of and than restart my accuracy seems to increase slightly. I was wondering if this is all I can expect from this device or it 5m is a standard accuracy for GCing. Any help would be appreciated.

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Every consumer GPS receiver has an accuracy of 3 to 5 meters under ideal circumstances.

Since both you and the CO have that accuracy, the location of a cache has a theoretical offset which can be up to 10 meters. Under not-so-ideal circumstances it might be even more. But usually I find caches in 0-5 meters from ground zero.

 

If you approach a cache the best thing you can do is put away your phone and start looking with your eyes.

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5m should be fine for geocaching. Getting to 0m isn't going to guarantee a find. GPSr units can have up to 30ft (10m) variation, so the initial coordinates may not be exact anyway because of the hider's device, then add in the variation from your device! I also primarily use a LG smart phone for geocaching and can get down to about 12ft (4m) at best. What I do, is get within 20-30 feet (8-10m) and PUT THE SCREEN DOWN! I look around and say "where would be a good place to hide something?" and begin searching. Once you have more experience, you start to get a feel for typical hiding places (people call that geosense). Don't get discouraged if you can't find some, even experienced players have off days. I hope all of this was helpful. Good luck and welcome to geocaching!

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That's actually the possible expected error, so in your case plus or minus 5 meters. If it was a known, accuracy the computer would correct it.

 

That being said that's pretty close to what you can expect with most devices, and it's good enough for geocaching. Remember you're not looking for the co-ords, you're looking for the cache. That means if the hiders GPS was off by 3 feet and yours is perfect, you'll still appear to be off by 3 feet. Then there's also the possibility that the hider didn't take a perfect reading. Maybe stood next to the cache to take the co-ords. Or maybe someone else didn't put it back in the original spot. Either of those, perfect co-ords n won't help either as you will be at the right co-ords, but the cache won't be there.

 

So, like others have said, when you get withing 3-5 meters start looking for the cache.

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I am currently using a Samsung Galaxy s3 as my GC device running Locus Map Pro. I seem to only be able to achieve an accuracy of about 5m (ie when I am at a predetermined point the compass says I still have about 5-7m to go). If I switch the gps of and than restart my accuracy seems to increase slightly. I was wondering if this is all I can expect from this device or it 5m is a standard accuracy for GCing. Any help would be appreciated.

 

you can get a closer idea of exactly where the cache is by using waypoint averaging. drop a waypoint with gpsaveraging (application) in three places that should be the points of a triangle, about five or ten feet apart, from the supposed gc location. import those to locus, and see if they all line logically.

 

if they do and you still can't find it, the cache is

a) missing

B) micro

c) both(pointles)

 

I'll check logs of the cage isn't in the logical places, and skip it completely if it's a micro.

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Thanks guys this has been very helpful. I will not be so discouraged not when my device points to somewhere that a cache simply wouldn't be. Many thanks

 

I have seen several caches in that "somewhere that a cache simply wouldn't be." location. :) So a lot of times reviewing some of the logs may help before you give up.

Happy Hunting

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Thanks guys this has been very helpful. I will not be so discouraged not when my device points to somewhere that a cache simply wouldn't be. Many thanks

I have seen several caches in that "somewhere that a cache simply wouldn't be." location. :) So a lot of times reviewing some of the logs may help before you give up.

Happy Hunting

+1

Yeah, depending on the D/T rating, a cache could literally be anywhere. :)

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I have seen several caches in that "somewhere that a cache simply wouldn't be." location. :)
Yeah, some of my Favorites have been well-camouflaged caches that can't be "needle in a haystack" caches, because there is no "haystack". In 5-10 minutes, I've searched "everywhere it could possibly be", and then I have to get down to the business of figuring out where/how the owner actually did hide it.
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Thanks guys this has been very helpful. I will not be so discouraged not when my device points to somewhere that a cache simply wouldn't be. Many thanks

You may not be aware that there is a local geocaching group on Faceplant. HAVOC - Hunter Area Victims Of Geocaching.

https://www.facebook.com/groups/200574939438/

If you're in need of some hands on help they have local events where you can pick brains and find out what's happening at a local level. And it'll be their caches you're looking for.

 

edited for typo

Edited by colleda
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I am having trouble with my iPhone 6 geocaching app compass. It tells me I'm within a couple feet from a cache but then it shoots to a longer distance the other direction. (I.e. say I'm within 3 ft. North and then it changes to 27 ft. West.) How can I improve the accuracy of my compass? I haven't played in several years but I don't remember the accuracy being this off. Thanks!

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On 7/11/2017 at 2:14 PM, CoachS_2010 said:

I am having trouble with my iPhone 6 geocaching app compass. It tells me I'm within a couple feet from a cache but then it shoots to a longer distance the other direction. (I.e. say I'm within 3 ft. North and then it changes to 27 ft. West.) How can I improve the accuracy of my compass? I haven't played in several years but I don't remember the accuracy being this off. Thanks!

 

Most smart phones do not have a compass. Direction is determined by the changing of your position.That dial you see is just a direction indicator. As the satellites go in and out of view, the calculation of your position can change by thirty feet. When you're away from your destination, you don't notice the error. When, you get close, and the position of your destination becomes more important, that same error is still there. Some software averages the position so that you don't see the radical changes (kind of like the oil that a compass needle floats in).  Not much you can do about it besides putting the phone down and looking. Some handheld GPS units have magnetic sensors. They still have the same positional error, but they stay oriented in the correct direction.

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35 minutes ago, fishgeek said:

 

Most smart phones do not have a compass. Direction is determined by the changing of your position.

Are you sure about that? Every Android phone that I've had (including my current one, which is a couple years old, and not a high-end model) has had an electronic compass (aka "geomagnetic sensor").

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6 minutes ago, niraD said:

Are you sure about that? Every Android phone that I've had (including my current one, which is a couple years old, and not a high-end model) has had an electronic compass (aka "geomagnetic sensor").

 

I stand corrected. Haven't looked at that in a while. Apparently, any iPhone or Android that uses Google services is required to have an electronic compass. Should have Googled that 45 minutes ago.

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Yes, the iPhone 3GS was the first to have a magnetometer in the device to detect magnetic orientation. Only very very old smartphones don't have a magnetometer. If you're curious, you can just google for the specs for your phone.

Regarding the "shooting" the other direciton, that's not necessarily the compass's fault -- if you're pretty much on top of gz, then as your GPS's estimated location shifts around, the position of the coordinate relative to where your device thinks your location is will cause the target indicator to look like it's spinning and bouncing around.  (this is another reason I prefer the birds eye view rather than a magnetic compass on a digital GPS - smartphone or otherwise :P)

If your North indicator on the compass is spinning (regardless of the cache location) then your device may just need an orientation calibration. That would depend on the app and OS settings. (again, you can google for how to best calibrate your magnetic compass on your device)

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