Does elevation matter at all?

[+helloyo53]

Hi everyone.

 

So I just put a whole bunch of coordinates into my new GPS. All of them had an option for elevation, but I didn't know the elevation for any of them, so I just left it as is. Now, will this affect the accuracy of the coordinates at all, or will it not matter?

 

Hope this makes sense.

 

Thanks.

[+Indotguy]

Will not matter.

Edited June 20, 2010 by Indotguy

[Grasscatcher]

Now, when you do a "go to" and actually find the location of each of those coordinates, some GPSs (Most? Garmins) have a feature whereby you can "Reposition Here" for that point and it will ccorrect the coordinates to that exact location and ,in your case, also add the correct elevation.

[+ecanderson]

Hi everyone.

 

So I just put a whole bunch of coordinates into my new GPS. All of them had an option for elevation, but I didn't know the elevation for any of them, so I just left it as is. Now, will this affect the accuracy of the coordinates at all, or will it not matter?

 

Hope this makes sense.

 

Thanks.

It's a rare cacher that provides you with elevation info on a cache to begin with - it would be in the descriptive info on the cache page. It's not part of a normal cache page.

 

We get a few like that out here in Colorado, but owners put that info in as a matter of personal interest. The wicked caches are the ones where elevation counts a LOT and there's no elevation information with which to work! Classic examples out here are caches that could be at the base of a cliff, anywhere up the entire elevation of the cliff, or at the top. At least we know it's somewhere in between when the terrain rating shows up as a 5.0. So sometimes we search in entirely the wrong place first - at the top when it's at the bottom, or at the bottom when it's at the top. It's one of the hinky things about placing a cache in the Colorado mountain area!

[dancing_elk]

As stated above, most of the time, I have not found elevation to matter much. That said, I recently found a cache in a heavily wooded area where I was getting a fair amount of bounce by moving to the elevation level and following a contour line in the general area. I don't know enough about the guts of my system, but I assume that the altimeter is barometric, and not dependent upon satallite lock. Otherwise, I guess that I just got lucky.

[+StarBrand]

With the exception of steep near vertical cliffs - there is but one discrete location on the surface of the planet for each set of coordinates. No problem.

[Grasscatcher]

At no point in the OP's post do I see the word Cache....so why assume that the coordinates are "cache coordinates" ?

 

The question was whether the lack of elevation data would affect the accuracy of the coordinates.

 

Post #2 fully answered that question.

Post #3 was purely info on how to easily and accurately add that data later.

[+ecanderson]

At no point in the OP's post do I see the word Cache....so why assume that the coordinates are "cache coordinates" ?

Why shouldn't we? This is, afterall, the Groundspeak forum. While there are those who visit here for help with these devices who have zero interest in caching, they're the exception, and there's no reason at all that we shouldn't think "cache" by default. Others who visit here and assume we are NOT thinking cache simply do so at their own peril, and should plan for some initial confusion.

[Grasscatcher]

My mistake and please accept my most humble apologies!

 

I thought that the title of this portion of the forum was "GPS and Technology".

 

I must learn to read more carefully or at least learn to read and comprehend what a post actually says.....so sorry.

[+ecanderson]

My mistake and please accept my most humble apologies!

 

I thought that the title of this portion of the forum was "GPS and Technology".

 

I must learn to read more carefully or at least learn to read and comprehend what a post actually says.....so sorry.

Yes, it's "GPS and Technology" -- on the Groundspeak board, devoted to geocaching and related GPS games.

 

If someone posts in the "Getting Started" section, I assume they're not coming here to learn how to use their GPS in an aircraft, but rather, to figure out how to use it to find a cache.

 

As a result, I guess the rest of us default to "geocaching" unless specified otherwise in a post. Actually, most folks who come here about using their GPS for other purposes often just say so up front so we don't make the mistake.

 

If your profile accurately reflects your level of interest in caching, you do understand you're a very small minority of the participants at Groundspeak, right?

[Andronicus]

The other issue is that the GPS system is not very accuriate in the vertical. I think it is like ±20m. Not going to help alot on a cliff.

 

When I first got my Garmin Forrunner 305, I was upset that when I ran in a large circle, the elevation changed by 20m from the first time around to the second. I e-mailed Garmin, and they said that is because GPS is not very good for vertical. If you think of triganomatry, it kind of makes sense. The accuracy is likely more of a % than distance, and the even a small % of the distance from earth to the satalite is quite large.

[Andronicus]

Here is an interesting write up on it GPS Altitude.

 

http://gpsinformation.net/main/altitude.htm

[+ecanderson]

The other issue is that the GPS system is not very accuriate in the vertical. I think it is like ±20m. Not going to help alot on a cliff.

Cliff? We've got speed bumps taller than that out here!