GPS' and maps

[+Alexode]

Hi

 

Probably a silly question, but does a GPS (Garmin 62s or any other GPS) require installed maps to work, or can one only use the coordinates in order to locate the caches?

Also, are there any free maps one can download?

[+DyverDown]

As far as I know any GPS will work without maps... it will simply point you directly to the cache (or any other position on the earth for that matter)

 

The maps add details that can be helpful (ie: it's across a river, highway, mountain....)

 

They can also give driving guidance if they are routable

 

DD

[seldom_sn]

Free topo maps for the US at GPSfiledepot.com. For the whole world at garmin.openstreetmap.nl.

[+Team Periwinkle]

There are many sites with free maps available for download. I'm only familliar with free maps for Garmin units - I just have never owned a non-Garmin unit, so I've never tried to figure out maps for those.

 

http:///www.gpsfiledepot.com has a lot of free maps, along with good instructions on how to use them.

 

Here is a post I made about free KMZ maps from the Garmin website:

______________

Goofing around on forums reading about custom maps, and I reverse engineered a link and was surprised to see this folder allows listing of contents:

 

http://www.garmindev...rminCustomMaps/

 

You can download all of the KMZ files that Garmin has created directly from that link. I checked out a couple and they are pretty nice.

 

It is much easier to go directly to that link / folder than drill through all the forum postings in the forum below to find the same maps...

https://forums.garmi...splay.php?f=206

 

Perhaps this isn't the biggest hack in the world, and perhaps it has been discussed before, but perhaps someone will find it handy...

___________________

 

Here is a great way to get a very good, very detailed, free street / trail map of the entire United States, again repeating another post I made somewhere else:

___________________________

I was looking at an area with a lot of trails but no PDF/JPG or any kind of trail map that I could find anywhere to use to make a KMZ (custom map). The trails I wanted are on http://openstreetmap.org, so I started poking around to see if there was a way to get those onto my GPSr. The solution was amazing:

 

1) go to http://www.osmmaps.com/

2) download the IMG / zip file - took 3 hours, so I let it run overnight

3) Unzip the IMG file - for me, the US file was / is 3.5 GB (yes, gigabytes)

4) rename the IMG file (since my Garmin GPS supports multiple IMG files)

5) copy the IMG file to the "\garmin" folder on the SD card in my GPS

6) "Enable" the OSM map on the GPS

7) At this point, I couldn't see the trails on my GPSr that I could see on the openstreetmap.org website. I figured I was out of luck...but... So this step may only apply to my GPS (GPSMAP 62/78 series), but perhaps there are similar steps for other Garmin GPSr: go to SETUP MAP, ADVANCED MAP SETUP, DETAIL, select MOST, and bingo! I now have the entire US version of openstreetmap.org on my GPSr, including all the trails you can see on that website. Absolutely amazing.

 

Caveats:

I have read that the OSM map is a snapshot from ~2006 census data files, and there are some known inaccuracies in the data, especially in the Western US. OSM seems to be fine for me here in the NE, but buyer beware.

This IMG file is not transparent, so I can't see any other IMG files at the same time. I received directions on how to make it transparent, but I haven't yet.

This IMG file has no topo contours (and since it isn't transparent, I can't see the contours from my other IMG file, even with both of them enabled).

This IMG file is not a routable map.

________________________________

 

The only way that I found to test out maps was to download them and try them out on the GPSr. For me, here in New England, I eventually decided to pay the $$ for the Garmin 24K Topo Series, and I'm happy with my decision. And I tried a LOT of free maps before that, most of them from gpsfiledepot.

 

Regards

 

Dave

 

[+Alexode]

Cheers guys! A Garmin 62s will now be ordered on Friday (payday), and I'll have a look at the different options.

Reason I was asking was because the guy in the store said I had to buy maps for it, asked how much it cost, and he replied "$300". I asked if that was for Europe, Norway etc. He answered "this county"... I left

[+Glenn]

The salesman who was trying to get you to buy maps for the 62s either had no clue what he was talking about or trying to increase his commission. You can download and install maps to that GPS for free! You can find instruction on how to do this at http://www.gpsfiledepot.com/tutorials/how-to-load-maps-on-my-garmin-gps-unit/. You can also download the maps from that website and a few others. The instruction are the same no matter what website you download your maps from.

[tr_s]

The only way that I found to test out maps was to download them and try them out on the GPSr. For me, here in New England, I eventually decided to pay the $$ for the Garmin 24K Topo Series, and I'm happy with my decision. And I tried a LOT of free maps before that, most of them from gpsfiledepot.

 

Agree, paid for topos generally can't be beat. The fact the information has been reviewed by a centralised organization is worth some cash. This doesn't mean all of it is correct, but often has some degree of truth to it. The pay for topos for the county I live in do indeed have trails on them so rough they probably shouldn't even be on the map, but at least there is some notion to that a trail has been there, at some point far back in time. On OSM I encountered blatantly wrong / bogus information several times in a week. Still a cool project, and it's muuuuuch better than no map at all - but trust it as you do Wikipedia...

[team tisri]

As far as I know any GPS will work without maps... it will simply point you directly to the cache (or any other position on the earth for that matter)

 

The maps add details that can be helpful (ie: it's across a river, highway, mountain....)

 

They can also give driving guidance if they are routable

 

DD

 

^^ this

 

The GPS will tell you where you are and where your destination is. Assuming you're looking for a cache it will tell you the distance and bearing to the cache. If you've put maps in it that support routing it can tell you that instead of being 1.3 miles in a straight line it's 2.4 miles by road and which roads to follow to get there.

 

If you've got maps that don't support routing, or no maps at all, the GPS will still tell you which way to go to get to the cache. It just won't tell you if that's the best way to approach, if there's a river or a ravine in the way.

 

That said even if you've got maps that support routing unless the cache is on a recognised route the GPS will have to take a best guess when it comes to getting from the known routes to the cache. What it will probably do is route you as close as it can get, then just draw a straight line from there to the cache. That can cause issues - some time back I was using maps that didn't feature trails and attempted to navigate to a cache. The GPS took me on a route I hadn't expected, but luckily I realised what was going on before I went badly out of my way. What it had done was navigate me as close as it could get by road and then directly from that point to the cache. Unfortunately the nearest road to the cache was on the south side of the river, and the cache was on the towpath on the north side. Needless to say the last 300 feet or so would have been tricky...

[team tisri]

The only way that I found to test out maps was to download them and try them out on the GPSr. For me, here in New England, I eventually decided to pay the $$ for the Garmin 24K Topo Series, and I'm happy with my decision. And I tried a LOT of free maps before that, most of them from gpsfiledepot.

 

Agree, paid for topos generally can't be beat. The fact the information has been reviewed by a centralised organization is worth some cash. This doesn't mean all of it is correct, but often has some degree of truth to it. The pay for topos for the county I live in do indeed have trails on them so rough they probably shouldn't even be on the map, but at least there is some notion to that a trail has been there, at some point far back in time. On OSM I encountered blatantly wrong / bogus information several times in a week. Still a cool project, and it's muuuuuch better than no map at all - but trust it as you do Wikipedia...

 

If only it were that simple.

 

The downsides of the central management of the maps include them being permanently out of date with typically no means of correcting your copy even when you know it's wrong, having to pay and pay and pay again for each successive update, and a lack of detail in more remote areas and on trails.

 

I used to use the Garmin UK Topo maps and found that they were mostly good but lacked a lot of detail where trails where concerned. Sometimes a trail would be marked on the map when what was on the ground was little more than a dirt strip worn in the grass. Within a mile was a gravel track leading from the road to the parking area, easily wide enough to take two cars, that wasn't on the map.

 

A lot depends what you want to use the maps for. Given any map has to be verified on the ground using that tried-and-tested approach known as "looking where you're going" I find the OSM maps far more useful for hiking and cycling than the topo maps, in the UK at least. In the US the 1:100k topo maps are often so bad they are all but useless, next time we're heading that way I'll grab OSM maps.

 

I don't trust the routing in the OSM maps enough to use them for driving but even there the paid-for maps aren't a guarantee of success. Roads change, new roads are built, and the old maps fall out of date. Only last year I found myself on a section of interstate in the US that wasn't on my map, simply because it was built in 2010 and my map was from 2009. So even having paid for a map it was no help at all, it couldn't tell me what road I was on or where I should turn off it.

[Forkeye]

Is there any noticable speed differance between maps loaded into internal memory on an Etex 30 and those loaded on an micro sd card installed into the same unit, either in power up time time or in map drawing time.I have some maps which are copy written to a certain sd card ,I can load other Garmin maps onto the card as well,but cannot transfer the copy written ones off the card to internal memory,though they can be viewed and loaded form Mapsource / Basecamp they must go onto the card or they will be locked.Also does the Etex 30 transfer sd card maps into internal memory on power up?

[tr_s]

 

If only it were that simple.

 

 

Yes I think you are mostly right with this lengthy post. What I wanted to get through was simply that a publicly generated map will have its pitfalls as there is no verification process. Encyclopedia britannica vs Wikipedia pretty much. Wikipedia and Openstreetmap contains lots and lots of useful information you won't find anywhere else, but a large dose of skepticism is probably good when using the data.

 

Funny that you mention wilderness areas though - in Sweden OSM ain't so popular so the pay-for topos (based on the state survey board) contain much more useful info like trails in backcountry/mountainous areas. OSM coverage there is spotty at best but far better in populated areas. I'm doing what I can to enhance that though, and contribute data to the OSM project.

[+Atlas Cached]

 

If only it were that simple.

 

 

Yes I think you are mostly right with this lengthy post. What I wanted to get through was simply that a publicly generated map will have its pitfalls as there is no verification process. Encyclopedia britannica vs Wikipedia pretty much. Wikipedia and Openstreetmap contains lots and lots of useful information you won't find anywhere else, but a large dose of skepticism is probably good when using the data.

 

Funny that you mention wilderness areas though - in Sweden OSM ain't so popular so the pay-for topos (based on the state survey board) contain much more useful info like trails in backcountry/mountainous areas. OSM coverage there is spotty at best but far better in populated areas. I'm doing what I can to enhance that though, and contribute data to the OSM project.

 

All good points, but no person should ever rely 100% on their GPS for routing, regardless of the map source.

 

Garmin releases CityNav map updates 4 times a year and they are still missing information regularly!

 

I use maps from Switchbacks.com as I find them to be more useful and informative than any paid for map available.

 

Maps can be off, or incorrect, and due to atmospheric conditions or other mechanical issues, the GPS can be incorrect as well.

 

Let us not all remember, the GPS is a tool, to help guide you, but only an assistant. The most important tool you have is between your ears, and it should always override the GPS

 

I am surprised at how many posts there are from people complaining that they cant find a cache (etc) after they went directly to where their GPS directed them.

 

"Turn left now!"