Accurate Coordinates when hiding your own caches

[+Cuddlefish]

My search terms must be too broad because I'm getting loads of irrelevant hits.

 

I'm worried the coords I have listed for my new cache(s) may be inaccurate. I marked the spots I hid the caches, walked away, came back and marked them again. I did this 3 times and went with the coords that were closest to another. These are my first hides and I simply came up with this method on my own. I am using a Garmin ETrex H.

 

Is that a problem? Because of the trees all around, my signal bounced around somewhat. Should I go back and recheck the coords another day? Wait for the long list of DNFs?

 

Thanks for your ideas....

[+StarBrand]

Good technique. Don't worry. I am sure they are fine. Did you confirm they are close with a map? If so - relax. Enjoy the logs.

[+briansnat]

No need to fret over coordinates. One reading is all I ever take and 99 percent of the time they are fine. In fact I often get compliments for accurate coordinates. Most geocachers don't expect them to be dead on. I'm happy if they are within 30 feet and have encountered them 40, 50 and more feet off and could still find the cache.

Edited September 28, 2008 by briansnat

[+luckybobb]

Sounds like you did a good job with getting the numbers tight.

 

If there is a doubt you can always go back on a different day and check them, if you do try on a day when the weather is a little different (sunny when you hid it maybe a little cloudy when you check). I usually ,ake a few trips to check co-ords. before we post them but haven't had too many complaints.

[+Cuddlefish]

Well I must say it was reassuring to read of your experiences, Star, brian, Lucky.

 

I'm relaxing a little now. As we all know, when you go to the trouble of making a cute cache and scouting out a nice spot, you want it to be a fun experience for people to find it also.

[+Guinness70]

i tend to leave the GPSr on the spot for 5-10mintues and then pin the coords

I'm using a Garmin Colorad300

 

other GPSrs have "averaging" function

Edited September 28, 2008 by Guinness70

[+Wild Thing 73]

You have some good informative answers to your question.....I'll just add that I have Garmin Map 60CSx and with the 60csx I MARK the spot that I want as GZ (which is the spot of the container), then I lay the GPSr on the ground and click the average button...I let the GPSr average for about 15 minutes and at the same time I watch to see how close to 10 feet the averaging calculations get me....if I get 10-20 feet, I'm really happy and satisfied. There are so many factors at work against getting a good fix, that we must be happy with what I get..I have an eTrex legend Cx and a few time I have tried to use both to average...What a waste of time... WE just try to hard and I would say to that..."Do your best and just "let it go". Happy Trails

[+Cuddlefish]

Well I went back today and checked my way points from yesterday. They were pretty close. Not perfect, but heck, good enough.

[+AD0SB]

I havent hid any myself yet, but what I would recommend, would be to check its location on 3 different days, and when you get there, set the gps down and let it sit in one spot for 5 minutes or so. If a cache is off by 10 to 30 feet in any given direction its usually not so bad, but if its a nano and its off by 100' thats a different story.

 

I retrieved new coords for a cache owner about a month ago, and I took both my Garmin 60CSx and the Magellan Meridian Gold with, fresh batteries, walked up to the cache and set both down. Waited 5 minutes, wrote down the #'s from both, walked a couple hundred feet away and approached it from another direction and did the same. I did that 3 times giving me 6 sets of numbers. I then averaged the numbers...

 

That maybe going overkill, I would guess the accuracy on that one is less than 3 to 5 feet.

 

I have seen some caches where they specify the cache is within xx feet of the coords, thats not so bad.

 

But if it is a location with difficult terrain and extremely heavy cover, having the accuracy sure helps. Nothing is worse than spending hours looking for a cache after a half hour hike, to claim a dnf to find the coords were off by 200 to 300 feet because of whatever reason. and then spend another half hour hiking back out...

[+luckybobb]

Also keep in mind that if the numbers are off by too much the people looking for it will let you know.

[+Kohavis]

I use a Venture HC and on every hide I use waypoint averaging. I let it run for a few minutes and as it takes more and more readings, it displays the error as it decreases. When it gets to 7 or 8 feet, I stop and save it.

[+ncfinn]

I go to the spot and wait for the GPSr to settle down. Then for the next ten or so minutes I write down all the readings I get. I throw out the extremes. I then see if any one reading is considerably more common than any other reading. If not, I take the average of all of them.

I then return different day of the week and different time of day (this seems to give me a different set of satellites) and do it all over again.

The final set is an average of the two collected sets.

 

I thought everybody did something similar, I did not think that anybody just glanced down once and went with that. I now understand why some co-ords are so far off.

[+Marcas_Found]

I use a Venture HC and on every hide I use waypoint averaging. I let it run for a few minutes and as it takes more and more readings, it displays the error as it decreases. When it gets to 7 or 8 feet, I stop and save it.

 

This is the same method we use and have never had any complaints. Another method that seems to be popular is to walk to the cache from 50 ft away and hit "mark point" right when you walk up to it. Both seem pretty accurate for the Garmins.

 

If you want to really "geek out" spend some time to learn how your GPSr averages its position as you walk along. Setting it down in one location for 5 mins without "averaging" the position may do nothing to give you a better GZ. It all depends on the unit.

 

-galaP-

[+Cuddlefish]

Both my caches were found within hours of being published. And given they were not in obvious spots, I'd say my coords were pretty good! Yippee!

[+Fuchsiamagic]

I just take one reading, then plot it on a Google Maps aerial photograph. As long as it's not in the middle of a wood, I can usually see by surrounding landmarks if it's at the right spot or not. If not, I just adjust the co-ords until it is. The beauty of using this system is that it's not dependant on the position of the GPS satellites on the day.

Edited September 30, 2008 by Fuchsiamagic

[+Kohavis]

I just take one reading, then plot it on a Google Maps aerial photograph. As long as it's not in the middle of a wood, I can usually see by surrounding landmarks if it's at the right spot or not. If not, I just adjust the co-ords until it is. The beauty of using this system is that it's not dependant on the position of the GPS satellites on the day.

 

I wouldn't rely on Google maps info to tweak GPS coordinates. The GPS data is far more accurate than Google's.

[+Cuddlefish]

I just take one reading, then plot it on a Google Maps aerial photograph. As long as it's not in the middle of a wood, I can usually see by surrounding landmarks if it's at the right spot or not. If not, I just adjust the co-ords until it is. The beauty of using this system is that it's not dependant on the position of the GPS satellites on the day.

 

Except.... many caches around here *are* in the woods - just like the two I mentioned in this thread!

[+Cuddlefish]

duplicate

Edited September 30, 2008 by jacqueli

[+vw_k]

I check my accuracy on my GPSr, 6 metres is really good for me, and 15 or under I am happy with, if I'm happy with the accuracy I mark the waypoint, walk away and try to navigate back to the cache from different directions, if the arrow points in the right direction from about 5 metres away I consider that to be really good.

[+Polarbz]

We wait until the GPS is Satellite accuracy is as good as its going to get (say sub 20' or 10') and take a reading. Then we check that reading against the Google-Earth maps and coords and, if they are too far off (5 points), we try to figure out why and maybe take another reading.

[wildmaninreed]

My search terms must be too broad because I'm getting loads of irrelevant hits.

 

I'm worried the coords I have listed for my new cache(s) may be inaccurate. I marked the spots I hid the caches, walked away, came back and marked them again. I did this 3 times and went with the coords that were closest to another. These are my first hides and I simply came up with this method on my own. I am using a Garmin ETrex H.

 

Is that a problem? Because of the trees all around, my signal bounced around somewhat. Should I go back and recheck the coords another day? Wait for the long list of DNFs?

 

Thanks for your ideas....

 

With 36 hides under our belt now & We been caching for just under 7 months.

When we hide a cache. We'll mark the hide, Walk off in different directions & have the GPSr lead us back to it. We'll do this about 2 or 3 more times with more marks & leading back to the cache. Then we pick the waypoint that shows us the closest to the cache & that is the coords we use.

99% of the time when cachers find & log in our hides they say the coords were Right On or they let us know at the many Meet & Greets we have been to.

 

We to use th etrex H & think it the best on the market at its price. For any price for that fact.