Placing cache using Google Maps?

[+TombRaid3r]

I'm wondering if a GPS is even necessary to actually place a cache. Can it be done using the coordinates on Google Maps? For example, I'm thinking of placing a cache in an area I know pretty well. I can locate this area on Google Maps, zoom in to almost the exact location and see the coordinates under my mouse pointer. How accurate would this be?

[Pup Patrol]

I'm wondering if a GPS is even necessary to actually place a cache. Can it be done using the coordinates on Google Maps? For example, I'm thinking of placing a cache in an area I know pretty well. I can locate this area on Google Maps, zoom in to almost the exact location and see the coordinates under my mouse pointer. How accurate would this be?

 

Guidelines:

 

http://www.geocaching.com/about/guidelines.aspx

 

1. Listing Guidelines for All Geocaches

 

1. Technical Requirements

 

Listings must contain accurate GPS coordinates.

 

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. Projecting waypoints from a specific location already defined by set of coordinates is permissible. For geocaches that include additional waypoints see the guidelines specific to those cache types.

 

B.

Edited August 1, 2013 by Pup Patrol

[+TombRaid3r]

I'm wondering if a GPS is even necessary to actually place a cache. Can it be done using the coordinates on Google Maps? For example, I'm thinking of placing a cache in an area I know pretty well. I can locate this area on Google Maps, zoom in to almost the exact location and see the coordinates under my mouse pointer. How accurate would this be?

 

Guidelines:

 

http://www.geocaching.com/about/guidelines.aspx

 

1. Listing Guidelines for All Geocaches

 

1. Technical Requirements

 

Listings must contain accurate GPS coordinates.

 

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. Projecting waypoints from a specific location already defined by set of coordinates is permissible. For geocaches that include additional waypoints see the guidelines specific to those cache types.

 

B.

 

Thanks. I only ask because today I found a cache that was about 25 feet away from where the marker was on the satellite imagery. I was thinking that if I had placed that cache, I would've looked at the map and saw that the marker wasn't where the cache was. The markers on the satellite maps are usually spot on, so I'm not sure what happened in this case. It's possible the cache could've been moved accidentally.

[+niraD]

Thanks. I only ask because today I found a cache that was about 25 feet away from where the marker was on the satellite imagery. I was thinking that if I had placed that cache, I would've looked at the map and saw that the marker wasn't where the cache was. The markers on the satellite maps are usually spot on, so I'm not sure what happened in this case. It's possible the cache could've been moved accidentally.

You're assuming that the marker on the satellite image is accurate.

 

Sometimes, the satellite images for Google Maps are detailed and well-calibrated. Other times, they aren't as detailed (you can't zoom in far enough) and/or they are poorly calibrated. I've seen examples where the satellite images have been off by 100ft or more.

[+T.D.M.22]

People move caches all the time, unfortunately. That plus the inherent inaccuracy of every GPS could make up 25 feet easily. Now speaking of Google Maps; Yes the co-ords are accurate-relative to other co-ordinates. However the images are not. By that I mean I could place a cache on my car outside, and get the co-ords, but on the maps, everything could me say 12 feet to the east. And since the Google satellite image is a combination of high detail satellite, and airplane pictures, pretty much stitched together, there are overlaps and duplicates that do occur.

[Mr.Yuck]

Thanks. I only ask because today I found a cache that was about 25 feet away from where the marker was on the satellite imagery. I was thinking that if I had placed that cache, I would've looked at the map and saw that the marker wasn't where the cache was. The markers on the satellite maps are usually spot on, so I'm not sure what happened in this case. It's possible the cache could've been moved accidentally.

You're assuming that the marker on the satellite image is accurate.

 

Sometimes, the satellite images for Google Maps are detailed and well-calibrated. Other times, they aren't as detailed (you can't zoom in far enough) and/or they are poorly calibrated. I've seen examples where the satellite images have been off by 100ft or more.

 

The Google Earth coordinates in my area, per a Google Earth junkie Geocaching pal of mine, are said to be consistently within 6 feet. Hey, that's just what he tells me, and only applies to my area. On the other hand, the guidelines have been quoted, and I have indeed seen 2 caches that I can recall being archived after it became apparent, and the cache owners admitted to using Google Earth to obtain the coordinates. Kids in both cases.

[+TombRaid3r]

I guess the cache could just be placed using traditional methods, and then compared to the sat images. It's nice to have more than one reference.

[+T.D.M.22]

I guess the cache could just be placed using traditional methods, and then compared to the sat images. It's nice to have more than one reference.

 

That really is the best Idea. I place a cache, take down my co-ords and put them on the page, but the co-ords take you a block away. Now if I looked at those co-ords on Google I would see they are a block away. That would give me the clue that something is wrong and I should re check what I have.

[+The A-Team]

I guess the cache could just be placed using traditional methods, and then compared to the sat images. It's nice to have more than one reference.

Like in T.D.M.22's example, the satellite imagery should only be used to check for boneheaded errors in your coordinates, like if they're a block away or miles away. Beyond that, the imagery should not be used. That includes "fine-tuning" the coordinates. Odds are you'll actually be fine-tuning your coordinates in the negative direction. Trust your GPS.

[+TombRaid3r]

It might not be the best for everyone, but for me, I prefer the marker on the map to be accurate on a satellite image. I mainly use the official Geo app on my iPhone. There is a compass mode that will point you to the coordinates, or there is map mode that shows an overhead view in either regular street maps or satellite. What I normally do, is have it in map mode with the satellite imagery (I believe it uses Apples maps, but not sure). I use the image to get to the marker, and then I just use my eyes. This works fairly well around town and where there are landmarks. In deep woods under tree cover, it'd be a different story, I suppose.

 

So, if the marker is not in the right spot on the sat image, it throws me off. I tend to trust the map more than my iPhone GPS. It's accuracy, like most units, is probably only 10-30 feet. For example, I could be standing at a bus stop and know that's exactly where I'm standing by looking at the sat image, but the little blue dot on the screen shows me standing out in the street. I guess none of this is really an exact science, at least not with consumer-grade GPSr's.

[AZcachemeister]

We (you, me, everyone else) can't control the accuracy of Google Maps, Google Earth, and/or whatever else. As already stated, in some areas these products are spot-on and highly reliable...in other areas of the world they are not.

 

Geocaching is a real-world, outdoor treasure hunting game using GPS-enabled devices. Participants navigate to a specific set of GPS coordinates and then attempt to find the geocache (container) hidden at that location.

 

There are enough issues that can dilute GPS accuracy, and learning how to compensate (and when) are important factors in using the equipment. Adding an unknown like 'Did this CO use Google Maps to get his numbers, and how far off is Google Maps in this area?' creates unnecessary difficulty in locating the container.

 

You are free to use whatever method you like to find caches, but please remember a GPS MUST be used to get the co-ordinates in order to hide/place them.

 

It's the GPS Stash Hunt, not the Google Maps Stash Hunt.

[+niraD]

So, if the marker is not in the right spot on the sat image, it throws me off.

I've found hundreds of geocaches using only the satellite images of Google Maps, so I understand. But as has been pointed out, geocaching is about using accurate GPS coordinates, not about using markers on Google Maps.

 

If you want to use markers on Google Maps, then you could try creating a mystery/puzzle cache like GCY2YH, but you'll still need to incorporate accurate GPS coordinates at some point (as this one does).

[+TombRaid3r]

Google Maps seems pretty accurate in my area, as does my iPhone. I found my house on Google, put the pointer on the room I was in and wrote down the coordinates. Then, I used the Geo app on my iPhone and got those coordinates. They were nearly identical to Google. Also, the "my location" dot in the app was not only on my house, it was right over the section of house I was in.

 

For phone vs Google Maps coordinates, lat was different by 0.001 and long matched exactly.

Edited August 3, 2013 by TombRaid3r

[+edscott]

I'm wondering if a GPS is even necessary to actually place a cache. Can it be done using the coordinates on Google Maps? For example, I'm thinking of placing a cache in an area I know pretty well. I can locate this area on Google Maps, zoom in to almost the exact location and see the coordinates under my mouse pointer. How accurate would this be?

 

Although anyone that can read a map could do it, or could realize the satellite image of that particular area is not of adequate quality, it is not allowed. You can however get a cheap cellphone and hide caches to your hearts content.

[+terratin]

Google Maps might not be accurate everywhere. Here in Copenhagen it is pretty much spot on. On the other hand, I solved a mystery on the other side of the country lately where I really wondered if my solution was correct because the coordinates pointed towards the roof of a building. With that in mind I was really confused about the GPS signal I got. In the end I found the coordinates were spot on, but 50m away in google earth.

[+edscott]

Google Maps might not be accurate everywhere. Here in Copenhagen it is pretty much spot on. On the other hand, I solved a mystery on the other side of the country lately where I really wondered if my solution was correct because the coordinates pointed towards the roof of a building. With that in mind I was really confused about the GPS signal I got. In the end I found the coordinates were spot on, but 50m away in google earth.

 

Yes since the camera can not be directly overhead from every spot on the ground, a tall building may be obscuring the actual coordinates.

[+TombRaid3r]

Thanks everyone, I will keep all this in mind when caching. Sounds like Google Earth might be OK to use as a "sanity check" if the maps in that particular area are accurate, but GPS is best.