“Find your own cache”
- pprass
- 10000 or more caches found
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- Location: Port Macquarie
“Find your own cache”
We are curious to know how new geocachers (and possibly the more experienced ones as well) determine the co-ordinates when placing a cache.
This topic has been discussed many times before and it is well covered in the wiki and “Helpful Hints for Newcomers” in the General Chit-Chat forum, but still for some cachers there seems to be a basic problem in obtaining accurate co-ordinates for a location.
We have come across a few new cachers who have had “bad” co-ords and some are very appreciative when you point out how they can improve their accuracy; while others don’t even bother to respond or worse still respond with “look harder” or “google maps rule”
When we place a cache, apart from letting the GPS settle in the one spot for a few minutes (and the spot is the actual hiding spot BTW, not 15 metres away as we are heading back to the car as an after thought ) we then test the marked co-ords by “finding our own cache”. That means that we walk away about 20 – 30 metres from GZ and then use the marked co-ords to find the cache we just placed. We do this about 3 or 4 times until we are satisfied that we have accurate co-ords. There are of coarse a lot of factors that interfere with this process – tree cover, proximity to a cliff, bad satellite day etc, but that is when we put in a hint to help the cacher. And that’s another thing – if you have good co-ords you don’t have to put in a hint as well. We only put in a hint if the cache is really tough, or if we know that there is an issue with getting a clear signal. It seems to us that cachers are lately ignoring how "bad" some co-ords are because they have read the hint before even leaving home and go straight to the hiding spot without even checking the distance on their GPS - yes we all play differently, but isn't using your GPS the basic principle of this game?
So what do others do? How do you make sure that you have the best possible co-ords that you can get?
Regarding accuracy, this is the general rule that we follow:
0 – 5 metres = Spot on co-ords and essential when searching for a nano in the bush or in a high muggle area in the city.
5 – 10 metres = Acceptable tolerance giving the cacher a bit of a hunt and making them think of possible hiding spots.
10 – 15 metres = On the verge of unacceptable and definitely not acceptable for micro’s or nano’s. We have heard that some cachers place caches that are 10 to 15 metres out on purpose to make the hunt more difficult – not in the spirit of the game we say.
15 - …. = Unacceptable distance. Makes it a very difficult hunt and usually results in a DNF.
Hope to hear from others and especially newbies.
This topic has been discussed many times before and it is well covered in the wiki and “Helpful Hints for Newcomers” in the General Chit-Chat forum, but still for some cachers there seems to be a basic problem in obtaining accurate co-ordinates for a location.
We have come across a few new cachers who have had “bad” co-ords and some are very appreciative when you point out how they can improve their accuracy; while others don’t even bother to respond or worse still respond with “look harder” or “google maps rule”
When we place a cache, apart from letting the GPS settle in the one spot for a few minutes (and the spot is the actual hiding spot BTW, not 15 metres away as we are heading back to the car as an after thought ) we then test the marked co-ords by “finding our own cache”. That means that we walk away about 20 – 30 metres from GZ and then use the marked co-ords to find the cache we just placed. We do this about 3 or 4 times until we are satisfied that we have accurate co-ords. There are of coarse a lot of factors that interfere with this process – tree cover, proximity to a cliff, bad satellite day etc, but that is when we put in a hint to help the cacher. And that’s another thing – if you have good co-ords you don’t have to put in a hint as well. We only put in a hint if the cache is really tough, or if we know that there is an issue with getting a clear signal. It seems to us that cachers are lately ignoring how "bad" some co-ords are because they have read the hint before even leaving home and go straight to the hiding spot without even checking the distance on their GPS - yes we all play differently, but isn't using your GPS the basic principle of this game?
So what do others do? How do you make sure that you have the best possible co-ords that you can get?
Regarding accuracy, this is the general rule that we follow:
0 – 5 metres = Spot on co-ords and essential when searching for a nano in the bush or in a high muggle area in the city.
5 – 10 metres = Acceptable tolerance giving the cacher a bit of a hunt and making them think of possible hiding spots.
10 – 15 metres = On the verge of unacceptable and definitely not acceptable for micro’s or nano’s. We have heard that some cachers place caches that are 10 to 15 metres out on purpose to make the hunt more difficult – not in the spirit of the game we say.
15 - …. = Unacceptable distance. Makes it a very difficult hunt and usually results in a DNF.
Hope to hear from others and especially newbies.
- caughtatwork
- Posts: 17017
- Joined: 17 May 04 12:11 pm
- Location: Melbourne
- Contact:
Re: “Find your own cache”
The wiki, for interest.
http://wiki.geocaching.com.au/wiki/Accurate_location
http://www.caughtatwork.net/geocaching/ ... inates.zip (Zipped PDF)
http://wiki.geocaching.com.au/wiki/Accurate_location
http://www.caughtatwork.net/geocaching/ ... inates.zip (Zipped PDF)
- Papa Bear_Left
- 800 or more hollow logs searched
- Posts: 2573
- Joined: 03 April 03 12:28 am
- Location: Kalamunda, WA
- Contact:
Re: “Find your own cache”
The problem with "find your own cache" is that, if there's something that's affecting your accuracy on that day, it'll just lead you back to the same wrong spot.
Ideally, multiple visits on different days is best practice, to rule out temporary glitches. Failing that, allowing at least several minutes is better than just taking one or two readings in quick succession.
Two other tips that I've gleaned from many "Please can you fix the coords on my new cache, UMP?" situations:
- Write your coords down on the spot, not when you get home. There's regularly new caches at home coords, where the car was parked, or at the GZ of the multi that the hider found just before or after placing their cache!
- Check your coords on Google Maps or similar. Online maps can often be out by quite a few metres, but it'll at least catch fat-fingered typos and some of the previous situations.
Ideally, multiple visits on different days is best practice, to rule out temporary glitches. Failing that, allowing at least several minutes is better than just taking one or two readings in quick succession.
Two other tips that I've gleaned from many "Please can you fix the coords on my new cache, UMP?" situations:
- Write your coords down on the spot, not when you get home. There's regularly new caches at home coords, where the car was parked, or at the GZ of the multi that the hider found just before or after placing their cache!
- Check your coords on Google Maps or similar. Online maps can often be out by quite a few metres, but it'll at least catch fat-fingered typos and some of the previous situations.
Re: “Find your own cache”
Newer GPSrs seem to have reduced the skill requirements for taking co-ords by an awful lot and most of the caches I've found that have been placed over the last 18 months or so have had pretty good co-ords (I reckon).
With my old Etrex, when placing a cache under heavy cover (e..g a tree or a shelter), I had a technique which appealed to me a fair bit -
1. Take a wp reading anywhere near the cache (doesn't need to be that accurate)
2. Head in a cardinal direction for 40-50m and set the GPSr to find the wp.
3. Follow the arrow (slowly) and see how far it's going to miss the cache by.
4. Adjust the intersecting co-ord accordingly (at my latitude, .001 of longitude = 1.5m, .001 of latitude = 1.9m)
5. Repeat until happy - this will give an accurate value for the intersecting co-ord
6. Repeat from another cardinal direction 90 degrees from the first.
e.g.
Take wp reading
Go south 50m from the cache and follow the arrow towards the wp
If you are going to pass 3m to the left of the cache, add .002 to the longitude
Repeat until the arrow consistently guides you through the cache.
Move to a position 50m east of the cache and follow the arrow towards the wp
If you are going to pass 2m to the left of the cache, subtract .001 from the latitude
Repeat until you are consistently going through the cache
Your wp should now be a pretty good estimate of the cache's position.
The assumption is, of course, that you have clear skies around GZ, but not right at it - but this isn't always the case (i.e. the cover may extend for a long way from GZ).
I hadn't read dak's document before, but I found it full of interesting stuff and it should be recommended reading for all cache hiders.
I'd especially like to reinforce the bits about knowing what to do when your co-ords may not be perfectly accurate (high EPE, displayed co-ords changing rapidly or by large values, arrow jumping around a lot, bad configuration of constellation, etc). In these situations either come back another day, make the hide good and obvious and/or leave a good hint. It's one thing to have people thinking you're a mongrel for placing a well-camouflaged and/or devious hide - it's quite another to have them thinking you're a mongrel because you're too incompetent to be able to supply decent co-ordinates
With my old Etrex, when placing a cache under heavy cover (e..g a tree or a shelter), I had a technique which appealed to me a fair bit -
1. Take a wp reading anywhere near the cache (doesn't need to be that accurate)
2. Head in a cardinal direction for 40-50m and set the GPSr to find the wp.
3. Follow the arrow (slowly) and see how far it's going to miss the cache by.
4. Adjust the intersecting co-ord accordingly (at my latitude, .001 of longitude = 1.5m, .001 of latitude = 1.9m)
5. Repeat until happy - this will give an accurate value for the intersecting co-ord
6. Repeat from another cardinal direction 90 degrees from the first.
e.g.
Take wp reading
Go south 50m from the cache and follow the arrow towards the wp
If you are going to pass 3m to the left of the cache, add .002 to the longitude
Repeat until the arrow consistently guides you through the cache.
Move to a position 50m east of the cache and follow the arrow towards the wp
If you are going to pass 2m to the left of the cache, subtract .001 from the latitude
Repeat until you are consistently going through the cache
Your wp should now be a pretty good estimate of the cache's position.
The assumption is, of course, that you have clear skies around GZ, but not right at it - but this isn't always the case (i.e. the cover may extend for a long way from GZ).
I hadn't read dak's document before, but I found it full of interesting stuff and it should be recommended reading for all cache hiders.
I'd especially like to reinforce the bits about knowing what to do when your co-ords may not be perfectly accurate (high EPE, displayed co-ords changing rapidly or by large values, arrow jumping around a lot, bad configuration of constellation, etc). In these situations either come back another day, make the hide good and obvious and/or leave a good hint. It's one thing to have people thinking you're a mongrel for placing a well-camouflaged and/or devious hide - it's quite another to have them thinking you're a mongrel because you're too incompetent to be able to supply decent co-ordinates
- Yurt
- 4500 or more caches found
- Posts: 1509
- Joined: 01 May 09 10:08 pm
- Location: Northern Suburbs, Sydney
Re: “Find your own cache”
I would normally mark a waypoint (and label it!) when I've got a good spot selected and the accuracy is pretty good i.e. 3-4m. Then return later with the cache and use the waypoint to find the spot. If it's a bit off then take another. The problem is then whether to average them or just use what you think is the best.
I've got no idea how anyone uses Google Maps or Earth to hide or find caches. Before we got a GPS we went looking in our local area and got 0 from 5. Next day we had a GPS and found them all easily. Mind you with a year's experience behind us I reckon I can spot a cachey location from a decent distance in many areas.
I've got no idea how anyone uses Google Maps or Earth to hide or find caches. Before we got a GPS we went looking in our local area and got 0 from 5. Next day we had a GPS and found them all easily. Mind you with a year's experience behind us I reckon I can spot a cachey location from a decent distance in many areas.
-
- 1800 or more caches found
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- Joined: 02 December 07 8:29 am
- Location: Cranbourne East, Victoria
Re: “Find your own cache”
And a hint is also good for sensitive areas when you don't want over zealous hunters destroying the area.pprass wrote:if you have good co-ords you don’t have to put in a hint as well. We only put in a hint if the cache is really tough, or if we know that there is an issue with getting a clear signal. It seems to us that cachers are lately ignoring how "bad" some co-ords are because they have read the hint before even leaving home and go straight to the hiding spot without even checking the distance on their GPS
Re: “Find your own cache”
Hiya PPrass (waving!)
Good topic!
What we tend to do is scout a location one day taking a couple of WP's and then move away and follow the arrow back (but I must admit we don't usually move 50 metres away - more like the 20m you mentioned or less )
We then go back with the cache on another day and follow the arrow to the spot - if it is "out" by more than 5 metres we then take more WP's and follow the arrows again. If M hasnt been with us when scouting the location earlier we get him to try out the co-ords to get fresh eyes.
I must say tho with our cheapy yellow GPSr - tree coverage affects our readings for sure - whether it be on hiding caches/taking our own WP's or finding caches/following other people's WP's but we usually get there in the end!!
The one thing we did do on purpose I must admit tho is with the Puzzles and Multis we took the readings pretty much DIRECTLY OVER the hiding spot as we figure the hard work has been done (especially in solving the puzzles with those ones!! ) and the cache should be reasonably easy to find (not forgetting that tree cover will always make it a bit out methinks) but with the traditional we placed last month we purposely took the reading about 2-3 metres away to provide just a wee bit more of a challenge . As far as we know everyone has eventually found it - well lets put it this way - there havent been any DNF registered .....
Seeya
GJMMelb (J)
Good topic!
What we tend to do is scout a location one day taking a couple of WP's and then move away and follow the arrow back (but I must admit we don't usually move 50 metres away - more like the 20m you mentioned or less )
We then go back with the cache on another day and follow the arrow to the spot - if it is "out" by more than 5 metres we then take more WP's and follow the arrows again. If M hasnt been with us when scouting the location earlier we get him to try out the co-ords to get fresh eyes.
I must say tho with our cheapy yellow GPSr - tree coverage affects our readings for sure - whether it be on hiding caches/taking our own WP's or finding caches/following other people's WP's but we usually get there in the end!!
The one thing we did do on purpose I must admit tho is with the Puzzles and Multis we took the readings pretty much DIRECTLY OVER the hiding spot as we figure the hard work has been done (especially in solving the puzzles with those ones!! ) and the cache should be reasonably easy to find (not forgetting that tree cover will always make it a bit out methinks) but with the traditional we placed last month we purposely took the reading about 2-3 metres away to provide just a wee bit more of a challenge . As far as we know everyone has eventually found it - well lets put it this way - there havent been any DNF registered .....
Seeya
GJMMelb (J)
Re: “Find your own cache”
That seems against the spirit of the game to me. I'm certainly glad that none of our local cachers do such acts.GJMMelb wrote:with the traditional we placed last month we purposely took the reading about 2-3 metres away to provide just a wee bit more of a challenge
Hoojar
- homedg
- 1550 or more caches found
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- Location: South West Sydney
Re: “Find your own cache”
You read my mind and beat me to the post Hooj.Hoojar wrote:That seems against the spirit of the game to me. I'm certainly glad that none of our local cachers do such acts.GJMMelb wrote:with the traditional we placed last month we purposely took the reading about 2-3 metres away to provide just a wee bit more of a challenge
Hoojar
Deliberately misposting co-ords?
- Richary
- 8000 or more caches found
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- Location: Waitara, Sydney
Re: “Find your own cache”
If I find my coords are out after a couple of comments, I make a return visit and see. Sometimes they are, sometimes they aren't. Usually I will take another set and average them. I also do this when placing for the first time if the sat lock isn't that brilliant.
I think it funny when on a recent hide I had 2 comments about the cache being about 12 foot out. C'mon - when was the last time your GPSr pretended it has better than 4 metres accuracy?
I think it funny when on a recent hide I had 2 comments about the cache being about 12 foot out. C'mon - when was the last time your GPSr pretended it has better than 4 metres accuracy?
Re: “Find your own cache”
Hi Hoojar and homedgHoojar wrote: That seems against the spirit of the game to me. I'm certainly glad that none of our local cachers do such acts.
Hoojar
We certainly didnt mean for it to be against the spirit of the game, that's absolutely for sure - we thought 2-3m was within the scope of GPSr accuracy ....anyway everyone has found it (presuming that no-one has not been able to find it and not logged a DNF) One person took 2 attempts and her child found it the next time - she wasn't expecting it to hidden the way it was, so missed it the first time - it's a regular size container - not a nano, micro or small (of which we have found quite a few that have been more than 2-3 metres from GZ and ditto for other sizes)
Anyway we wont do it again!!
Apologies and we stand corrected - we'll get a new reading next time we do a maintenance visit.
GJMMelb (J)
- tronador
- 6500 or more caches found
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- Location: Lidcombe,Sydney, NSW
Re: “Find your own cache”
Ditto- totally agree with Hoojar and HomedgHoojar wrote:That seems against the spirit of the game to me. I'm certainly glad that none of our local cachers do such acts.GJMMelb wrote:with the traditional we placed last month we purposely took the reading about 2-3 metres away to provide just a wee bit more of a challenge
Hoojar
There is an Avg button on the Gps. When you Mark a waypoint, I press Avg ( average) instead of OK and leave the GPS to average until it reaches about a 100 measurement count. It then takes these readings and averages them. Then I save the wpt. AND give the wpt a name.
- pprass
- 10000 or more caches found
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- Location: Port Macquarie
Re: “Find your own cache”
Excellent - and then I hope you use those co-ords to go and "find your own cache"tronador wrote:.. It then takes these readings and averages them. Then I save the wpt. AND give the wpt a name.
GJMMelb - 3 to 4 metres out is within acceptable tolerances as per our table and no-one should be concerned about that error whether it was intentional or not.
As per Richary's comment - maybe they meant 12 metres out! 12 feet is getting a bit pedantic and shouldn't bother anyone.
- Richary
- 8000 or more caches found
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- Joined: 04 February 04 10:55 pm
- Location: Waitara, Sydney
Re: “Find your own cache”
Maybe they did, but it brings up another problem. I don't actually want every cache hidden with dgps and 10cm accuracy. If my unit brings me within 10cm there is no fund in the hunt unless it includes a lot of vertical possibility as well.pprass wrote:As per Richary's comment - maybe they meant 12 metres out! 12 feet is getting a bit pedantic and shouldn't bother anyone.
In the case of mine it should be pretty obvious roughly where it is going to be, and there are only a few bushes up there it could be under. But sub metre accuracy - no thanks. There would be no challenge in finding 99% of caches.
Re: “Find your own cache”
Thanks for these articles. Extremely interesting. I am learning heaps. Could you please explain this though, it totally lost me:
"GPS receivers are usually set to True North by default, however, if you require someone to project a
waypoint to find your cache, take careful note of the North Reference setting of your GPSr, and make it
clear in the cache description what North Reference they need to use for the projection."
"GPS receivers are usually set to True North by default, however, if you require someone to project a
waypoint to find your cache, take careful note of the North Reference setting of your GPSr, and make it
clear in the cache description what North Reference they need to use for the projection."
caughtatwork wrote:The wiki, for interest.
http://wiki.geocaching.com.au/wiki/Accurate_location
http://www.caughtatwork.net/geocaching/ ... inates.zip (Zipped PDF)