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Pokey and Reese

Make sure my coordinates are correct?

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I am setting my first few hides and am paranoid about giving good coordinates! I have a garmin oregon 450 and am using the waymark averaging feature. I have gone to the sites on different days and different times for at least 5 samples for each. Problem is, when I go back and try to find the spot I want to put the cache, it seems that the coordinates put me several meters off! I live in the Rocky Mountains and am wondering if the mountains may be interference? Should I be this paranoid, or just, as others have said, "Trust the device"?

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I am setting my first few hides and am paranoid about giving good coordinates! I have a garmin oregon 450 and am using the waymark averaging feature. I have gone to the sites on different days and different times for at least 5 samples for each. Problem is, when I go back and try to find the spot I want to put the cache, it seems that the coordinates put me several meters off! I live in the Rocky Mountains and am wondering if the mountains may be interference? Should I be this paranoid, or just, as others have said, "Trust the device"?

It depends on what "several meters off" means. If it's only something like 3-5 meters, then you're doing just fine. I wouldn't worry too much unless my GPSr was taking me more like 10+ meters away.

 

FWIW, I used to use the waypoint averaging on my 450, but stopped some time ago. A firmware update about a year ago changed the way the GPSr performs at low speeds (including when stopped), so my GPSr seems to wander a lot more than it used to. I found the averaging wasn't doing as good a job as it used to, so I stopped using it. Now I walk up to GZ, mark a waypoint, and walk away. I'll keep going away from GZ in various directions and then walking back up to it, adjusting the waypoint incrementally as necessary, until I can regularly get to within a few meters from different directions. I'll repeat the process on at least one other visit, and sometimes more. I now seem to be getting the same accuracy I used to get with the averaging.

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I am setting my first few hides and am paranoid about giving good coordinates! I have a garmin oregon 450 and am using the waymark averaging feature. I have gone to the sites on different days and different times for at least 5 samples for each. Problem is, when I go back and try to find the spot I want to put the cache, it seems that the coordinates put me several meters off! I live in the Rocky Mountains and am wondering if the mountains may be interference? Should I be this paranoid, or just, as others have said, "Trust the device"?

It depends on what "several meters off" means. If it's only something like 3-5 meters, then you're doing just fine. I wouldn't worry too much unless my GPSr was taking me more like 10+ meters away.

 

FWIW, I used to use the waypoint averaging on my 450, but stopped some time ago. A firmware update about a year ago changed the way the GPSr performs at low speeds (including when stopped), so my GPSr seems to wander a lot more than it used to. I found the averaging wasn't doing as good a job as it used to, so I stopped using it. Now I walk up to GZ, mark a waypoint, and walk away. I'll keep going away from GZ in various directions and then walking back up to it, adjusting the waypoint incrementally as necessary, until I can regularly get to within a few meters from different directions. I'll repeat the process on at least one other visit, and sometimes more. I now seem to be getting the same accuracy I used to get with the averaging.

 

Thanks! It's about 1 - 3 meters off. I will try your method and see how close those coordinates are to my averaged ones.

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1-3 meters of is pretty good, you likely won't get it the exact same every time you go there. The general rule is to get about 10 meters from the cache then start looking for it.

 

And the cache will only be where you put it for the first hider-caches tend to move from a foot or two to 10 feet away, so the co-ords might appear off for the other finders. Nothing we can do about it.

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1-3 meters of is pretty good...

Agreed. If you're getting this kind of accuracy, you're doing really well. I wouldn't worry any further about it.

 

I just looked at your past finds, and it looks like you live in the Airdrie area or somewhere close by. With all that flat land and lack of trees, you should be able to get excellent coordinates with very little effort. :laughing: I'm not at all surprised now that you're getting that kind of accuracy. I have to contend with mountains, hills, gulleys, and giant trees in this area, so I'm usually happy if the GPSr will bring me to within 10 meters!

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I actually am in the Bow Valley and a couple if my hides here will be snuggled up to Mt Lady Mac so those ones are a bit worrisome. Others will be down in the bottom of the valley so at least a bit more open land! Thanks for the pep talk, I'm definitely feeling better about the coords. I'm doing a series of 9 caches all leading to a 10th and final puzzle cache - based on movie titles. Hopefully it will be a fun series!

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I am setting my first few hides and am paranoid about giving good coordinates! I have a garmin oregon 450 and am using the waymark averaging feature. I have gone to the sites on different days and different times for at least 5 samples for each. Problem is, when I go back and try to find the spot I want to put the cache, it seems that the coordinates put me several meters off! I live in the Rocky Mountains and am wondering if the mountains may be interference? Should I be this paranoid, or just, as others have said, "Trust the device"?

Consumer grade GPS is not more accurate than about 5m. So expect to have slightly different results every time, but it shouldn't be more than 10m except when you indeed have reflections to deal with.

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It's about 1 - 3 meters off.

 

A detailed hint is nice if the cache is hard to find even with good 3-meter-range coordinates. Or up the difficulty rate so folks know it's a tough find. I like the good-hint option because there's less wear and tear on the environment (depends on how sensitive the area is and if things are likely to be trampled or moved around (rocks, logs, etc.)

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It's about 1 - 3 meters off.

 

A detailed hint is nice if the cache is hard to find even with good 3-meter-range coordinates. Or up the difficulty rate so folks know it's a tough find. I like the good-hint option because there's less wear and tear on the environment (depends on how sensitive the area is and if things are likely to be trampled or moved around (rocks, logs, etc.)

 

Thanks for the tips! I have thought of decent hints (I hope!) the difficulty has me stumped. I've looked through some of the tougher finds I've gotten and the ratings sometimes don't seem to jive! I'm going to give it a good guess and then ask the first few finders what they thought. Us that an OK thing to do?

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It's about 1 - 3 meters off.

 

A detailed hint is nice if the cache is hard to find even with good 3-meter-range coordinates. Or up the difficulty rate so folks know it's a tough find. I like the good-hint option because there's less wear and tear on the environment (depends on how sensitive the area is and if things are likely to be trampled or moved around (rocks, logs, etc.)

 

Thanks for the tips! I have thought of decent hints (I hope!) the difficulty has me stumped. I've looked through some of the tougher finds I've gotten and the ratings sometimes don't seem to jive! I'm going to give it a good guess and then ask the first few finders what they thought. Us that an OK thing to do?

 

Use the GC Difficulty/Terrain calculator:

 

Geocache Rating System

 

Difficulty:

* Easy. In plain sight or can be found in a few minutes of searching.** Average. The average cache hunter would be able to find this in less than 30 minutes of hunt.*** Challenging. An experienced cache hunter will find this challenging, and it could take up a good portion of an afternoon.**** Difficult. A real challenge for the experienced cache hunter - may require special skills or knowledge, or in-depth preparation to find. May require multiple days / trips to complete.***** Extreme. A serious mental or physical challenge. Requires specialized knowledge, skills, or equipment to find cache.

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The general accuracy of our handheld units is in the 10 to 25 foot range. One can reasonably expect that you will get readings within that error zone on any given day/time. Close enough. Not sure this little activity would be much fun if all coordinates led us within 1 mm of the cache each and every time.

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My QA department keeps offering to give lessons on getting good coords. No one has taken him up on his offer. But he insists that our coords must be the best possible. We average the coords, then he checks from a hundred feet away, from several directions. Adjust as necessary.

We went looking for a 4.5/3 cache recently. The coords are 40-70 off. (We did not find it, so we aren't sure.) Perhaps it was a proximity issue with another cache? (And he lied?) Perhaps he lied to make it harder? (Completely unacceptable.) Perhaps his device was just not very accurate? Perhaps he never tried to check his coords for accuracy? Whichever, this is not acceptable! Your coords are supposed to be accurate.

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I would have a fit if my coords were found to be that far off! I guess it's better for me to be a bit paranoid and try everything before I publish! I tried coming at each site from multiple directions today and that helped me get some confidence in the coords. Thanks to everyone for the advice and feedback - it really is helpful.

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You can see what kind of accuracy you're getting by pressing on the little green bars at the bottom of your main screen. If you see 5 meters, you're doing awesome. If you're seeing 18 meters, I'd be concerned. In my experience, if you are next to a rock face or in a ravine or if there is a lot of tree cover, that's when the accuracy is bad. If you're standing in the middle of a flat area and no trees, the accuracy can be excellent. If the accuracy's bad, make sure you give a good hint and perhaps some flagging tape.

 

When I hide a cache, I will admit I'm kind of lazy about it, but still seem to get good results. I rarely go back on a 2nd day. I may go find some other caches and then come back, but that's about it. What I do is to mark a waypoint and check the GPS accuracy (as I have explained above). Presuming there are no major issues, I will wander around a bit and see how close the waypoint is when I keep coming back to GZ. Some places you hide a cache it's really obvious there's going to be problems. Like when you see the accuracy at 18 meters. When you see anything anything like 5-8, you're probably OK.

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