Cache Placement Etiquette

[BLAA]

I was reading some of the posts in the FTF Etiquette topic and this question arose...

As a matter of "Cache Placement Etiquette" should the coordinates be verified through Google Earth/ Google Maps or is a GPS unit sufficient?

Now sometimes this is not so significant ... for example, a hide in the woods. It’s kinda hard to pinpoint which tree your cache might be in. So I am not talking about rural hides (but a hide in a tree shouldn't show up as being in a lake!)

So this is really an urban caching question. With the satellite view there is the ability to practically ensure that you have posted the "real" coordinates. I do this with all of my hides ... and I think several of the members of this board must do so too, because your coordinates have been SPOT ON.

Many of you know that we live in California - but about 10% of our 700 finds are in Manhattan as a result of us getting to NYC about 10 times each year ...which explains what I am doing on this board. We have a couple of new cachers out here in our area who are doing a GREAT job populating the area with about 25+ caches between them in the last two months. But they just can't seem to get the hang of checking the coordinates on Google Earth or Google Maps - an error of 60, 80, 100+ feet can be a big deal when looking for an urban cache. And I take from reading these boards that there are some similar issues in NYC. Some of the coordinates of the new caches out here have been so far off that the caches start to take on the nature of a puzzle cache. The all time whopper of them all was a cache with a coordinate error of over 1100 feet! Fortunately we didn't have the ability to go out for this one when it was published ... the next morning I was reading the initial DNF logs which questioned placing a cache in a residential area. The CO posted a note saying that it was not in a residential area and that he would check things out later. In looking at the posted coordinates I noticed that the decimal value for both the longitude and latitude were identical ... which was so unlikely it had to be wrong. So using the cache name and description I surmised what establishment the cache was referring to and looked up the address of the one nearby. I was a more than a bit disappointed to find that another local cacher figured this out about 20 minutes before I got there and beat me to the FTF.

This was clearly an accident but it also could have been discovered by the CO by just inspecting the satellite photo.

Satellite inaccuracies are a fact of life when you're looking for something with a GPSr ... before the high quality photos were available you had the inaccuracy of the hider's GPSr plus the inaccuracy of the finder's GPSr. But most of the hider's inaccuracy can be overcome by checking out the Satellite photo. So in general, should the CO verify coordinates with the photo before publishing the cache? Or is the hider's GPSr inaccuracy part of the game?

[addisonbr]

I feel strongly enough about it that I have some stuff about using Google Maps in next week's article on "Placing Your First Cache".

I suppose it really breaks down into two questions. One, should a cache owner error-check his/her work? Two, should a cache owner use Google Maps (etc.) as a tool?

I think the answer to one is absolutely. It takes only a few moments of your time and can save hunting cachers literally hours. It's only fair. My answer to two is that I think it's a great tool and heartily recommend it. I personally never place a cache without fine-tuning the coordinates on Google Maps. Especially in an urban environment where the hides have to be particularly concealed, and the Google Maps offer such resolution and detail... I've been known to nudge my coords by 1/1000th of a minute just to make sure the arrow is pointing precisely at the right corner of the fence (or whatever).

I can accept that other people might be comfortable with looser coordinates than I am, but knowing that the urban jungle creates reception issues, not everyone has top-of-the-line whiz-bang GPSrs, a lot of newer cachers are using GPS-enabled cell phones (which are not particularly accurate), and we even have a few members who cache using only Google Maps or USGS Topo maps alone - I just try to give them the best coordinates I can and try to relegate the error bands to their end of the search.

[EastVillageFamily]

Coordinates for geocache placement should be triple checked using as many different methods as possible. That cannot be stressed enough.
A cellphone is not accurate enough to be the only source for coordinates of any kind for geocache placement.
Google maps data does shift occasionally, causing it to vary, but it is generally better than the average 8ft circle of a good GPSr in the hands of a practiced user.
Find a known reference point in your area on Google Maps/Earth, and check it regularly to see if they have moved their reference point (it happens without warning).
A growing number of Urban cachers do not own GPSrs, they print out Google maps.

With all that said, we try to duplicate the average geocacher's search experience. That means:

Approaching the cache from all possible directions and watching what the GPSr does.
Visiting GZ several different times at different times of day.
With a little practice, you can interpolate a centroid that is almost as accurate as Google. With sampled data over 24 hours, you can get down to 1-2 foot accuracy.

Repeatability should be the most important aspect of the search.

You may find some approaches include huge satellite signal reflections off of nearby surfaces. You may find some times of day create huge satellite bounce. Or either of these two factors may create a situation where the E/W coord is highly accurate and the N/S number is 100 feet off (this scenario happens most often in NYC, but the reverse sometimes occurs.)

We know these things, because we play a lot of games with our GPSrs, but this knowledge also allows us to help cachers who say, "I tried today, but suddenly my coords seemed to be 100 feet off". We know that in certain situations, they can just come back at a different time of day. At several difficult locations for reception we have made our hints clearer.

Last piece of unofficial advice: The Admins will look at your cache listing using Google Earth, to compare it to the surrounding area, before they publish it. So, if you have a look too, you might see that it isn't so clear online whether or not those Rail Road tracks are abandoned, and you can mention that you know they are. Or you can see that it looks like the cache has been placed in the water, rather than the shore.

[lekogm]

All of the coordinates I've published are averaged by my GPSr over 2 to 5 minutes. I then will wander in from as many paths as possible and verify that they are the best possible coordinates.

[peeves79]

I guess I suck because I only take one reading and go with that. I didn't have a GPS that could take hundreds of readings and then average them. I was just using my trusted nuvi. I would just take one reading, walk away and use the coords to see how close I would get. I had no problems getting within 5 feet of any of my hides. Perhaps I am lucky in the fact that I have them placed in areas that don't disturb people's GPS you like in Queens.

[EastVillageFamily]

[BLAA]

Perhaps another dimension is that the cache description and hide characteristics really should be transparent. As terrific as Google Maps is sometimes verifying with Google Maps may not be enough ... for example if there has been recent construction ... or if the detail of the photo is not so hot (it seems that the more populated areas get a higher quality photo).

I completely agree with EastVillageFamily that the coordinates must be repeatable ... but if there are issues with the terrain, the Google Map photo or the quality of the GPSr then it’s always good to know that in advance - the cache description could easily say "you will not get accurate readings at GZ due to the tall buildings ... but the coordinates are accurate, based on Google Maps ... or the Google Map photo is worthless". Some of the recent placements out in my area have had very poor coordinates - after a few of these misadventures searching for these CO's caches we were able to take this into consideration and subsequent searches were somewhat easier ... even with poor coordinates.

In Manhattan a Google Map photo of accurate coordinates trumps the best GPSr... you need to get into a park before the accuracy gets acceptable.

[EastVillageFamily]

[addisonbr]

Google Earth is notoriously flighty. I have always found Google Maps to be far more reliably repeatable. Google Earth is certainly easier and more fun to use, but the Google Earth satellite photos roam around a *lot* relative to given GPS coordinates.

[EastVillageFamily]

I have always found Google Earth to be reliable. But then I always work with known reference points, to double check any measurements.

[gerkmax]

[addisonbr]

I used to have that dynamic Google Earth .kml file installed too, that queries the database for geocaches as you pan around and had the exact same experience... The caches against the satellite photos were just not consistent. They were close of course, but one day it would show a cache in one the shore; the next it would be 5 feet out into the water. I'm not familiar enough with the mechanics of the two technologies to describe why that might be the case, but when I found Google Maps to be much more consistent and repeatable I switched to GM and have been very happy.

For those who care:

http://www.geocaching.com/kml/buildnetworkkml.aspx

[EastVillageFamily]

[BLAA]

[addisonbr]

GC.com's own version of Selective Availability. Ironic. And yet they don't do the same scrambling on their Google Maps gc app, even for non-subscribers.

[scratches head]