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My cache coordinates is Off?!

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Me and my friend hid a geocache using a Magellan gps how ever the coordinates are apparently 50+meters off. But when i looked at the coords on google maps it is dead on. Can someone help?

Cache:http://www.geocaching.com/geocache/GC62JC8_a-rocky-situation?guid=8adaaa31-f92f-4dc5-abb5-efc7ce14d53f

Cache.jpg

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Me and my friend hid a geocache using a Magellan gps how ever the coordinates are apparently 50+meters off. But when i looked at the coords on google maps it is dead on. Can someone help?

Cache:http://www.geocaching.com/geocache/GC62JC8_a-rocky-situation?guid=8adaaa31-f92f-4dc5-abb5-efc7ce14d53f

Cache.jpg

 

http://coord.info/GC62JC8

 

Don't rely on google maps.

 

Go back out to the location, and take numerous readings with your gps. Let it average the coordinates for a while.

 

Make sure you are using the datum format that GS uses.

 

Help Center → Other → Conversions

http://support.Groundspeak.com/index.php?pg=kb.page&id=208

 

1.3. WGS-84 and HDD(D)° MM.MMM Datum and Format

 

Why do we use WGS-84 and HDD(D)° MM.MMM Datum and Format?

 

Most GPS receivers are set coming out of the box with WGS-84 and HDD(D)° MM.MMM Datum and Format. Using this setting will be less likely to confuse new GPS owners.

 

Help Center → Hiding a Geocache → Review Process: Hiding a Geocache

1.3. How to Get Accurate Coordinates

http://support.Groundspeak.com/index.php?pg=kb.page&id=673

 

Walk away, then let the gps navigate to the coordinates you have chosen, to make sure that the coords are good.

 

When you get better coordinates, edit your cache page to post the updated coordinates, then enable it.

 

4.13. How do I update coordinates for my geocache?

http://support.Groundspeak.com/index.php?pg=kb.page&id=61

 

B.

Edited by Pup Patrol

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the coords in the map view in your post are:

 

43.511094 80.201018 in Decimal Degrees

 

the coords on your cache page in Decimal Degrees

43.51062 -80.20087

 

The coords you've entered on the cache page are ~180 ft from the illustration in your post

 

here's the map of the coords you entered on your cache page, from the cache, the is the third map link

 

https://www.google.com/maps?q=N+43%C2%B0+30.637+W+080%C2%B0+12.052+%28GC62JC8%29+

Edited by palmetto

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Forget the 'don't rely on Google'. For the most part, at least in North America, their alignments have done nothing but improve over the years. You did the right thing to use it to troubleshoot your problem. It can be a very useful tool.

 

Be sure your unit is set to WGS84 datum, not, for example, NAD27. The error you have is just about right for that kind of problem in your region.

Take more than one reading at different times and assure that they agree.

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is it possible that you "fat fingered" the input of the coordinates? That has happened to me more than once.

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Good point, K13, and sometimes not so much fat fingered as slipped a digit, so to speak.

 

I often find in GC101 classes, there's always some confusion about decimal vs. decimal minutes vs. data entry. More than once I've seen 39º55.862 entered as 39.55862. Leaves a much bigger error in most cases, though. Can't be the problem here, as 43.51XXXº would be a very long way from 43º51.XXX

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Forget the 'don't rely on Google'. For the most part, at least in North America, their alignments have done nothing but improve over the years. You did the right thing to use it to troubleshoot your problem. It can be a very useful tool.

 

The problem is geocaches are not exclusive to North America. Until Google is consistent throughout that world it's not a tool that should be relied upon for *any* geocache.

 

 

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Forget the 'don't rely on Google'. For the most part, at least in North America, their alignments have done nothing but improve over the years. You did the right thing to use it to troubleshoot your problem. It can be a very useful tool.
The problem is geocaches are not exclusive to North America. Until Google is consistent throughout that world it's not a tool that should be relied upon for *any* geocache.
And even in North America, there are places where the online images don't have the accuracy/resolution needed.

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Forget the 'don't rely on Google'. For the most part, at least in North America, their alignments have done nothing but improve over the years. You did the right thing to use it to troubleshoot your problem. It can be a very useful tool.
The problem is geocaches are not exclusive to North America. Until Google is consistent throughout that world it's not a tool that should be relied upon for *any* geocache.
And even in North America, there are places where the online images don't have the accuracy/resolution needed.

 

In our area, we had someone put a cache in a Little Library in their own front yard. Very nice cache, great location and all, but unfortunately they took the coordinates from Google maps and were .6 mile off. After several DNFs they did go out with a GPS and did post, in an OM log, the correct coordinates, but never had the actual cache coordinates corrected. The cache has been archived because of complete lack of response by the CO to numerous attempts by local cachers and the reviewer to contact them.

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The OP hasn't returned to this thread.

 

The cache owner disabled the cache a week ago. (Note: cache owner is not the OP.)

 

B.

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Forget the 'don't rely on Google'. For the most part, at least in North America, their alignments have done nothing but improve over the years. You did the right thing to use it to troubleshoot your problem. It can be a very useful tool.

 

Google maps is the best tool ever, too bad they dropped it from the Waymarking site. :(

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Forget the 'don't rely on Google'. For the most part, at least in North America, their alignments have done nothing but improve over the years. You did the right thing to use it to troubleshoot your problem. It can be a very useful tool.

 

The problem is geocaches are not exclusive to North America. Until Google is consistent throughout that world it's not a tool that should be relied upon for *any* geocache.

 

 

The OP is from Canada, and who said anything about "relying" on it anywhere? I don't "rely" on my Garmin, either. I use it as one datapoint at a given moment, just as I've been known to use Google as a double check due to its reliability in North America.

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In our area, we had someone put a cache in a Little Library in their own front yard. Very nice cache, great location and all, but unfortunately they took the coordinates from Google maps and were .6 mile off. After several DNFs they did go out with a GPS and did post, in an OM log, the correct coordinates, but never had the actual cache coordinates corrected. The cache has been archived because of complete lack of response by the CO to numerous attempts by local cachers and the reviewer to contact them.

Ah, whoa there, Nan. I'm from your 'neighborhood'. Must have been some other sort of 'operator malfunction'. NOWHERE in Colorado will you find Google satellite imagery misaligned by 0.6 miles. At present, I know of no area here where it's even 0.01 miles off.

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In our area, we had someone put a cache in a Little Library in their own front yard. Very nice cache, great location and all, but unfortunately they took the coordinates from Google maps and were .6 mile off. After several DNFs they did go out with a GPS and did post, in an OM log, the correct coordinates, but never had the actual cache coordinates corrected. The cache has been archived because of complete lack of response by the CO to numerous attempts by local cachers and the reviewer to contact them.

Ah, whoa there, Nan. I'm from your 'neighborhood'. Must have been some other sort of 'operator malfunction'. NOWHERE in Colorado will you find Google satellite imagery misaligned by 0.6 miles. At present, I know of no area here where it's even 0.01 miles off.

 

Well, I wasn't looking over his shoulder when he took the coordinates from the Google map, so I don't know what went wrong or why. All I know is that he said that's what he did.

 

http://www.geocaching.com/geocache/GC5F7WH_little-yellow-library?guid=60387076-8230-43ac-b624-a81eb439b84f

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In looking at the cache to which your post points, I see that the posted coordinates are N 38° 19.100 W 104° 43.800. Honesty, those DO seem a little 'round' to me, further indicating that there was an operator error involved. Odds of having decimal minutes in both N/S and E/W just happen come out to an even 0.X00 are about 1 in 10,000. Not everyone realizes that the coordinates at the bottom of a GE screen are following the cursor even after the screen is centered on the 'target'. Who knows? I surely wouldn't blame GE for that one.

 

Beware of 2nd hand anecdotal information!

 

For what it's worth, looking at the posts for that cache, using the 'correct' coordinates of N 38° 19.011 W 104° 43.120 in GE drops you in the front yard of the house that holds the library box.

Edited by ecanderson

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I think GE is a good tool to help but shouldn't rely on it. I have pulled up to a cache and the map view shows it in the middle of the street and I think it is off but my GPS takes me to it.

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I pre-plan my caching runs, and am a GSAK user. As a matter of course, I check out in advance any cache whose access is questionable. I find the satellite view from GSAK (which is coming from Google) consistently tells me upon which side of a small ditch the coordinates rest. That doesn't mean the cache is there, but when I'm standing on the spot, if I can take the time to generate an averaged waypoint, that's where I am almost every time.

 

It's reliable enough that when I place a cache, I always double check my placement with GE or GMap's satellite view just to be certain that I haven't fat fingered anything. A few times, there's been just enough difference that I've gone back out to get some additional readings and found that I must have been having a bad HDOP day during the original placement, and made corrections accordingly.

 

There are a few seriously precision measured benchmarks that are intentionally visible from the air. One easy one was just east on the grounds of the Denver Museum of Nature & Science and can readily be seen from above (see GC52E2). The difference in actual vs. coordinates with GE was about the 0.001 resolution we work to (about 4 feet at our latitude). I doubt that most of the folks placing caches take enough time to get their measurements that they'd get that close. You can still see the ground marker on Bing's aerial views.

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Sometimes my phone will show me quite far away...as much as two miles. It's always easy to tell when it does so, though. I believe in those cases it may be trying to place me at a cell tower location until the GPS signal can kick in and self-correct. It's always best to check the coordinates on a map, though. I always do before submitting. I think there are plenty of people who rely too much on only one source, be it the map view or only the numbers. I honestly don't know why anyone wouldn't double check...or even triple check.

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Sometimes my phone will show me quite far away...as much as two miles. It's always easy to tell when it does so, though. I believe in those cases it may be trying to place me at a cell tower location until the GPS signal can kick in and self-correct.

My wifi-only iPad will get its location from most any source, it even updates from wifi signals as I drive. And it may be tough to tell that the data is not obtained from the the most accurate source, GPS.

 

In this case, it looks like the cache coordinates are off. :anicute:

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Sometimes my phone will show me quite far away...as much as two miles. It's always easy to tell when it does so, though. I believe in those cases it may be trying to place me at a cell tower location until the GPS signal can kick in and self-correct. It's always best to check the coordinates on a map, though. I always do before submitting. I think there are plenty of people who rely too much on only one source, be it the map view or only the numbers. I honestly don't know why anyone wouldn't double check...or even triple check.

 

I assume you're talking about maps with satellite views.

 

I was looking at some caches in a park down the road from a place I'll be staying in November. It's in Beijing.

 

Take a look at the listing for this cache:

 

Then look at the Map view and switch between the Map and Satellite view. When looking at the map view the cache appears to be just to the left of a small square pond. When looking at the satellite view it looks like it's northeast of larger pond to the right. According to GPSvisualizer the two points are about a half a kilometer away from each other.

 

While maps may be pretty accurate in the North America, they can't be used by "anyone" to verify coordinates, if that is going to include everyone in the world.

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It's in Beijing.

IIRC, map providers in China are required to intentionally misalign their maps or something. That could be causing the large discrepancy you're seeing.

 

As for...

Forget the 'don't rely on Google'.

This is just plain bad advice. The wording of this statement implies that it's okay to rely on Google. It isn't okay.

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It's in Beijing.

IIRC, map providers in China are required to intentionally misalign their maps or something. That could be causing the large discrepancy you're seeing.

 

As for...

Forget the 'don't rely on Google'.

This is just plain bad advice. The wording of this statement implies that it's okay to rely on Google. It isn't okay.

 

Agreed. I suspected that misaligning maps (like the big red firewall) maybe be something mandated by the government. My point was mostly that if you're going to state that you don't know why *anyone* wouldn't use maps then that could include everyone, not just those that have the luxury of living in a place where the maps are very accurate and have a resolution good enough to identify features on a map such that they can be used to determine the location of a cache. Even when maps *are* very accurate, identifying which tree in densely wooded area is the one where the cache is located would be nearly impossible.

 

The guidelines state that a GPS must be used to obtain accurate coordinates because it works just about everywhere in the world where a geocache might be placed. It just wouldn't make sense to includes something in guidelines to allow maps to obtain coordinates, except in China, or dense wooded areas, or....

 

 

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It's in Beijing.

IIRC, map providers in China are required to intentionally misalign their maps or something. That could be causing the large discrepancy you're seeing.

 

As for...

Forget the 'don't rely on Google'.

This is just plain bad advice. The wording of this statement implies that it's okay to rely on Google. It isn't okay.

You seem to have neglected the remainder of that post and the content of subsequent posts. It can and should be relied upon as a double check of placement coordinates. If there's agreement, you know you're good. If there's not, then there's reason for concern, and usually NOT from Google.

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It can and should be relied upon as a double check of placement coordinates. If there's agreement, you know you're good. If there's not, then there's reason for concern, and usually NOT from Google.

If there's agreement, it's an indication that you likely didn't make a typo and your coordinates are in the ballpark. Of course, it could also be that you're unlucky enough that the map was misaligned by an amount similar to your poor coordinates.

 

If there isn't agreement, it's an indication that your coordinates may not be in the ballpark and you may have made a typo. Of course, it could also be that your coordinates are bang on and the map is just misaligned.

 

Satellite images can be used as a factor in determining the accuracy of your coordinates, but they should not be relied upon.

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Satellite images can be used as a factor in determining the accuracy of your coordinates, but they should not be relied upon.

Guess they did a lousy job in your neighborhood. Come on out here, and rely upon it with me. Over the past couple of years, Earth has never lied to me in this area of the country (nor a couple of others I've used it for). If there was a mismatch, it was on the GPS side. If there is a mismatch, it demands a revisit for updated readings.

 

I guess what I'm saying is that it is FAR too reliable to ignore here. Ever.

Edited by ecanderson

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Satellite images can be used as a factor in determining the accuracy of your coordinates, but they should not be relied upon.

Guess they did a lousy job in your neighborhood. Come on out here, and rely upon it with me. Over the past couple of years, Earth has never lied to me in this area of the country (nor a couple of others I've used it for). If there was a mismatch, it was on the GPS side. If there is a mismatch, it demands a revisit for updated readings.

 

I guess what I'm saying is that it is FAR too reliable to ignore here. Ever.

No, it's just consistent with the Guidelines:

 

You must visit the cache location and obtain the coordinates with a GPS device. GPS usage is an integral and essential element of both hiding and seeking caches and must be demonstrated for all cache submissions.

 

I guess by your line of reasoning, if I'm looking for one of your caches and I'm not finding it, or the Hint seems to imply it some distance off, I should put away my GPS and pull out my phone and consult GE, since that appears to be the reference method you're using. Come to think of it, the host of industries that rely on GPS technology should really be switching over to GE. I've heard of folks that rely on maps for finding caches (and some have found thousands of caches in this fashion). I didn't realize until now, that they were way ahead of their time ;)

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I guess what I'm saying is that it's so reliable, one could not in good conscience allow a mismatch between readings and GE here. It will be the readings that are in error.

 

If your mileage varies, I'd like to hear about it. This MAY still be a regional thing where it's dead nuts in some places and a bit misaligned in others. Each individual needs to compare their reality to GE to see if it's reliable for them. Like I say, your neighborhood may have ratty alignment. Mine definitely does not, and neither do any of the other areas (including out to Hawaii) where I've used it in recent history. It seems they've made it a point to clean up their act, and that most of the nay sayers are working from historical information.

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And then again, as someone hunting for a cache, there are places that Google Maps is more accurate than a GPSr. Midtown New York! I get close, then rely on the street map on the GPSr. The GPSr can have me a few blocks away. I don't know what method the local hiders use. But GPS reception can be terrible there.

Obviously, not the case with the OP.

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And then again, as someone hunting for a cache, there are places that Google Maps is more accurate than a GPSr. Midtown New York! I get close, then rely on the street map on the GPSr. The GPSr can have me a few blocks away. I don't know what method the local hiders use. But GPS reception can be terrible there.

Obviously, not the case with the OP.

The issue you are suffering under is multi-signal. It bounces of the buildings and the gps receives the same signal at different times and has trouble resolving it.

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I guess what I'm saying is that it's so reliable, one could not in good conscience allow a mismatch between readings and GE here. It will be the readings that are in error.

 

If your mileage varies, I'd like to hear about it. This MAY still be a regional thing where it's dead nuts in some places and a bit misaligned in others. Each individual needs to compare their reality to GE to see if it's reliable for them. Like I say, your neighborhood may have ratty alignment. Mine definitely does not, and neither do any of the other areas (including out to Hawaii) where I've used it in recent history. It seems they've made it a point to clean up their act, and that most of the nay sayers are working from historical information.

Not a nay sayer for either method particularly, but I understand that there are limitations to both approaches. As an example, we have very dense redwood groves in some very deep canyons in my area, where a gps signal is nearly non existent. Some users take gps readings, but still verify the position from online maps. This kind of begs two questions in my mind:

 

1. If you're gps didn't work so hot in this location, what makes you think mine is going to do any better?

2. If you're using an online mapping service, why would you assume it's accurate? It's not like the mapping service cares about the relative accuracy of its maps in the middle of a forest.

 

For the most part, caches hidden in these areas tend to have pretty explicit Hints, and or Letterboxing style instructions to find the cache. The reliance on either method is pretty much a big fail when it comes to geocaching.

 

Just an aside, but back in the day, it was popular to use a particular software package to calibrate park maps and overlay cache icons in order to get a relative position of the caches to nearby trails. There used to be (might still be out there), where you could download these maps for your own planning purposes. To calibrate the maps, you had to have three known locations, like the top of a hill/mountain or a trail junction, and align the map with these three known spots. Sometimes it worked pretty well, and sometimes it was a bit of a miss. I'm assuming that GE uses a similar method to calibrate its maps, and if so, my experience tells me it may not be all that reliable at times.

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Quick anecdotes on the reliability of the sat maps. Three years ago I checked a sat image, and it placed the cache on the Starbucks property, when it was actually on the Japanese restaurant property across the street.

 

On the other hand, I found an LPC based on the sat image only - I didn't even use the gpsr.

 

More recently, the sat images seem quite accurate in the eastern US.

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I would not rely on Google maps at all to tell me the truth about the location of anything.

I have seen their location of borders be way off. They said a park existed that did not. I had an argument with a reviewer

for placement of a geocache in a city that requires a permit to place one in the parks. I see no park I check with the city,

The city says no park, I proved my point with city map from the city web page and statement from city parks manager.

But the reviewer refused to believe, as far as he was concerned Google is GOD. Another incident, a wildlife refuge border problem.

I went to the website for that refuge and got map from them. I went to the border and took coords of the border. I submitted this info to the reviewer.

No! Google is GOD. The cache placement was on State property this time and 3/4 of a mile from the border to the wildlife refuge.

No! Google is GOD. Google maps are meant to be a reference only and not used for legal definitions My GPS has proven to me to be accurate to +-5 feet.

I even recorded the Earths crust movement of 35 feet after the Japan Earthquake. Confirmed by geologists. Numerous State employees kept telling me that their

Car GPS kept saying that they were driving in the ditch after that. The system has now compensated for this. Basically just use Google maps/ Earth as reference only.

Sometimes they are lucky and place it right and sometimes not.

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I would not rely on Google maps at all to tell me the truth about the location of anything.

I have seen their location of borders be way off. They said a park existed that did not.

I wouldn't, either! ... But I think you may have missed the actual topic here. It's the alignment of overhead imagery we're talking about, not the overlaid location of streets, borders or businesses on the map view. In fact, GE makes it plain that there are still quite a few minor (and some major) street alignment issues --- you see this when you overlay the streets on the more accurate satellite imagery.

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I would not rely on Google maps at all to tell me the truth about the location of anything.

I have seen their location of borders be way off. They said a park existed that did not.

I wouldn't, either! ... But I think you may have missed the actual topic here. It's the alignment of overhead imagery we're talking about, not the overlaid location of streets, borders or businesses on the map view. In fact, GE makes it plain that there are still quite a few minor (and some major) street alignment issues --- you see this when you overlay the streets on the more accurate satellite imagery.

Actually this is on topic. If they can get all that I have spoken of wrong then they can get cords posting wrong too.

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It's two entirely different systems (and corporate divisions, for that matter), Mn-treker. And NO mapping company gets it entirely correct. If they did, automotive GPS units wouldn't have to include a 'snap to road' feature even when they have a good fix. You'd be surprised at how much slop still exists in road alignment in some areas vs. reality. Even with a perfect fix, you'd see yourself driving off-road more often than you would believe! But again, these are entirely different systems, and the maintenance of each is a very different proposition. They should not be compared.

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Satellite images can be used as a factor in determining the accuracy of your coordinates, but they should not be relied upon.

Guess they did a lousy job in your neighborhood. Come on out here, and rely upon it with me.

Sigh.

 

Okay, I'll modify my statement as follows:

As a general rule, satellite images can be used as a factor in determining the accuracy of your coordinates, but they should not necessarily be relied upon. YMMV

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