Geocaching with my TomTom Unit

[mhigley]

all i want to be able to do is punch in a latitude and longitiude point and have the gps direct me there. but what i have found is it will only take me there if it is near a road. Then even at that it does not get me close to the cashe. if there is any way i would like to know
Thanks

 

[canderson]

Isn't going to work for you. Didn't work for me when I started caching (some 3300 finds ago), either! The "road snap" feature won't allow you to wander off a road when finding a cache until you're at least 150' or more away from the road. Only then will it produce real coordinate data on the satellite screen, an even then, you don't get the nice electronic compass of a handheld. That's when I relegated my TomTom GO720 to getting me to the general area of the cache, and picked up a decent purpose-built handheld Garmin to get me to ground zero.

That said, your ONE3 is a great tool for setting up a caching itinerary for a day, and for keeping track of what's out there and how to drive as close to them as possible. Of course, that isn't always a good thing -- gotta picture a cache located closer to the interstate highway than the frontage road -- well, you've no doubt seen the problem before!

If you're interested in being able to load caches to your ONE3 (especially if you have a Premium membership at gc.com) or are interested in talking about a capable handheld to augment your ONE3 for caching, let me know and I'll spill all here.

 

[gatorguy]

Heck, try a Geomate Jr, specifically made for geocaching. It may do just one thing, but does it pretty darn well. Dead simple to use, accurate. Best of all, CHEAP! About $70.

@Canderson, opinion on OpenCaching.com?

 

[canderson]

Heck, try a Geomate Jr, specifically made for geocaching. It may do just one thing, but does it pretty darn well. Dead simple to use, accurate. Best of all, CHEAP! About $70.

For an adult, the GeoMate lacks features that a cacher will soon come to expect on a decent unit. They JUST finally allowed PQs to be loaded on these units (although I hear there's a few bugs in the beginning), and while that's not the only major issue, it's certainly a big improvement.

@Canderson, opinion on OpenCaching.com?

If you refer to the game that Garmin just started playing, best of luck to them. I don't know what the malfunction is between Garmin and geocaching.com, but neither seem to be doing each other any good at present. The way Garmin has structured their operation (total lack of review of all submissions), it looks like it's going to be quite the train wreck. While the current method of reviewing caches can be a pain at gc.com, Garmin's approach may only make things worse for all of us. The hobby has enough issues with land managers, etc., without making things more difficult.

It certainly hasn't picked up any traction here in Colorado. We've got about a zillion caches in this state, and a great many right in this area -- none of which have been recorded at the OpenCaching site yet. The only place I'm seeing them listed is down in the Colorado Springs area, and it's a tiny fraction of what's here to play.

 

[gatorguy]

Same thing I'm seeing here. Not a great start, but that doesn't mean it won't succeed I suppose. Like you I have no idea what prompted Garmin's move into geocaching support via OpenCaching.

 

[canderson]

Same thing I'm seeing here. Not a great start, but that doesn't mean it won't succeed I suppose. Like you I have no idea what prompted Garmin's move into geocaching support via OpenCaching.

A variety of interesting little tidbits to add up, not in this order, but ...

Garmin support for opencaching.com begins
Garmin changes GPS icon for geocaching button selection from gc.com icon to the old treasure chest
Garmin releases Chirp units without discussion with gc.com
GC.COM drops Garmin to bottom of fieldnotes list

Opencaching | Geocaching Categories
opencaching.com new mascot... - Groundspeak Forums
Get in the Ring, Round 2: New Opencaching.com Poll Its Not About The Numbers

 

[canderson]

As for actually finding a cache with a TomTom, I should add the following note:

The OP owns a ONE3rd which does not support firmware versions beyond 8.016. Firmware that old displays the "road snapped" coordinates, not the real coordinates, on the satellite page. It is for that reason that his particular TomTom is nearly impossible to use for most urban caches and a lot of others as well. It will show his position at 90 degrees to the nearest road until he gets quite FAR from the road and the TomTom gives up trying to snap him to the nearest road position.

I and others complained that if a person were actually reading raw coordinate data vs. looking at a map, what they REALLY wanted was the REAL coordinate data, not some tweaked set of numbers on a road nearby. Road snap is fine, but don't lie about the latitude and longitude!

I don't know if TomTom heard our complaints in this regard or not, but with the advent of Navcore version 9.XXX firmware, the lat/long coordinates position on the satellite page are TRUE, not road-snapped coordinates. TomTom units released since 2009 have either come with 9.XXX firmware as shipped, or for the most part can be updated to newer 9.XXX firmware from their original 8.XXX firmware. However you get there, if you can, 9.XXX provides real latitude and longitude data.

For geocaching purposes, you'll need to set your TomTom's coordinate display (adjusted from the "Configure" button on the "GPS Status" satellite page) to the "Minutes (d?m.m')" (which gives you dd mm.mmm display) format that matches the posted coordinate format for geocaches. As I recall, that is NOT the default format for any TomTom model.

Those attempting to untether from the car and take a 9.XXX TomTom into the field to actually find a cache wont' find it as easy as with a decent handheld, even with real coordinate data. You'll have to keep your sense of N/S/E/W while you keep watch on the up/down ticking of the coordinate data on the display. A rough guide to distance in our part of the world is as follows:

For every 0.001 N/S difference between where you're standing and the cache coordinates, you're going to need to move another 6' or so. For example, if your latitude shows 40?01.335 and the cache is located at 40?01.340, you need to move 5 x 6' (about 30') further north.

For every 0.001 E/W difference between where you're standing and the cache coordinates, you're going to need to move another 4' or so. For example, if your longitude shows 104?59.520 and the cache is located at 104?59.540, you need to move 20 x 4' (about 80') further west.

OK - some obvious issues. Your TomTom is NOT water resistant, much less waterproof. It's NOT a purpose built handheld for backcountry use. Do NOT drop it in the drink. Further, your TomTom has nowhere near the battery capacity of a decent handheld. If you get a couple of hours out of it between charges, consider yourself lucky. Time can be extended through the use of external USB 'power boosters' like this one Amazon.com: New Trent Super-pack IMP500 5000mAh External Battery pack for 3G iPad, iPhone 4 4G, iPhone 3G 3GS, iPod Touch (1G 2G 3G), Motorola Droid , HTC Android Phones, Blackberry (curve, bold, tour, storm) Brand new: Electronics that will give you almost 4X additional run time. However, if you own any of the newer GO series (e.g., the GO740 or later) there isn't a simple USB/USB connection.

 

[gatorguy]

Pretty darn thorough post Canderson. Well done, and I'm sure a big assist to some TomTom owners not ready to commit to a handheld for real geocaching until they know for sure they'll enjoy it.

 

[canderson]

Aw heck - tweren't nuthin. Am working on a much fuller version.

 

[canderson]

TomTom Caching, Part 1

Geocaching With Your TomTom


Navigating in-Vehicle With a TomTom

One of the nice things about the TomTom automotive GPS products is that they were some of the earliest units to allow end-user customization and 3rd party applications. TomTom seems to be headed the other direction now, closing down access to the file system and locking down menus, but the key feature for geocaching with a TomTom remains – easy creation of custom POI files. [Note: this was written in January of 2011 before the newest 1XXX, 2XXX and Via TomTom models were provided this feature over web access, but in anticipation of that feature release].

Custom TomTom POI files are in a special format, and always have a filename suffix of “*.ov2”. A custom POI can also have an associated icon unique to that POI type, and it comes in the form of a *.bmp” image file. The root names of *.ov2 and *.bmp files must match. So if you want to create a custom icon as well, a file called geocaches.ov2 must be accompanied by a corresponding image file called geocaches.bmp. As a reminder, TomTom icon images must be 22x22 pixels in size, and saved as 24 bit color depth *.bmp files. There are tutorials on the web for creating your own icons. If you don’t need or want a custom icon, your TomTom has a selection from which you may choose.

You can create POI files from individual or Pocket Query *.gpx files acquired through the geocaching.com interface. My preferred tool for this purpose is GSAK (Geocaching Swiss Army Knife) available here -> www.gsak.net. It handles not only this task, but many others as well. Using macros, I can even take my PQ of an area and that of a friend, and compare them to see which unfound caches we have in common – a function often requested at geocaching.com, but as yet not delivered.

Premium members at geocaching.com have access to the Pocket Query system. I won’t try to detail the setup and execution of a Pocket Query, but it’s well worth the annual membership at geocaching.com, and is worth the entire price of the membership. Suffice it to say that you can download the results as a ZIP file, and the contents of that file are used to build your TomTom POI.

While some may consider it a bit of overkill, I build four different POI files for my TomTom units each week with new Pocket Query data. The first and most important of those is the POI list of caches in my area that I have not found. I then build a second POI file of my own caches, a third consisting of the caches I have already found, and a fourth of caches that I have found but that have subsequently been archived. Each has its own little icon on the map display to keep them straight, and I can turn each category on and off like any other POI on a TomTom. I’ll place my four hand-built icons here if you wish to steal any or all of them.

After loading your *.gpx file(s) into GSAK, it’s a simple matter of using the GSAK “File / Export” function and selecting “TomTom POI file” as your output format type. GSAK will create the *.ov2 file with whatever root filename you specify, and the filenames can be in the ‘long’ format. For example, mine are geocaches.ov2, mycaches.ov2, foundcaches.ov2, archivefoundcaches.ov2. Each has one of the above *.bmp files associated with it. For basic use, all you really need is one file of your unfound caches, and calling that geocaches.ov2 keeps it easy to spot in your POI list.

Another “TomTom-friendly” program that can handle conversion from *.gpx to *.ov2, but not as quickly, is Tyre, available here -> Tyre. After firing up Tyre, open your *.gpx file by selecting “File / Open” and from the “Files of type:” drop-down, select at the bottom, select “Garmin GPS Exchange Files”. Once your *.gpx file is loaded, select “File / Save As” and in the “Save as type:” box, select “TomTom POI Files”. Tyre will create your *.ov2 file using the name you supply.

Sadly, I know of no equivalent tools for the Mac. The above are all Windows-based applications.


Once you have your *.ov2 POI file built (and any *.bmp file you may have borrowed or created), just slide them right over into your big map folder on your TomTom and they’re ready to select and use from your TomTom. Mine are all located in the folder called North_America_2GB.


One nice feature of the TomTom is itinerary planning (although beware – this feature is NOT available on many of the dumbed-down EasyMenu TomTom models, all of which I’d avoid for their lack of front-panel functionality. Models employing this less desirable interface at the time of writing include all of the following: Ease (Start2 in Europe), XL335SE, XL335LE, XL335LM, XL350, XL350T, XL350M, XL350TM, (XL IQRoutes2 in Europe), XXL550, XXL550T, XXL550M and XXL550TM.) In addition, I would note that the models specified above will NOT allow you to directly enter coordinate data for navigation purposes! NOT good for caching!

You can built itineraries for your caching day using caches from your POI file. Scout out a decent route on the geocaching.com site, and you can enter each of up to 48 caches in an itinerary and execute it. Your TomTom will take you from cache to cache. I usually delete each cache from the itinerary as I arrive since you often won’t drive close enough to the actual cache location to cause it to be removed from the itinerary automatically. If you plan a monster day of more then 48 caches, just create a second (or third?!?) itinerary of 48 more.

 

[canderson]

TomTom Caching, Part 2

Finding Ground Zero With a TomTom

I’ve had questions asked both in geocaching and TomTom forums about trying to find a geocache (not just navigate to the area) with a TomTom automotive GPS. While certainly not ideal, some automotive GPS units can be used for this game. Some are hopeless.

Automotive GPS units incorporate a feature often referred to as “Road Snap”. The geolocation of roads is often not very precise (yet), and the real position of a road vs. the position recorded for that road in the map set of a GPS don’t always match. The reason that your little icon always seems to remain on a road is a function of Road Snap. The GPS takes your current known position and compares it to the map data. It then displays your icon’s position on a road on the map as close to your calculated coordinates as possible. This prevents your icon from wandering off the road all the time and producing a display that would have you thinking that you were having frequent off-road excursions all the time.

Like other GPS brands, TomTom also incorporates Road Snap in their units to keep your icon displayed on a road whenever possible. This is good. However...

All TomTom models are capable of displaying coordinate data. On many TomTom models, this is accomplished by pressing on the satellite bars on the righthand side of the screen. On some more recent models, you must navigate to the GPS Status page from the menu system. You would think that this coordinate data could be readily applied when searching for a geocache. But...

TomTom GPS units would traditionally display not the actual raw coordinate data as calculated, but the Road Snap “corrected” postion data on the coordinate display found on the GPS Status (satellite) display. As a result, if you were to watch the coordinate data as you walked away from a road, your latitude and longitude would continue to display a position ON road to a position closest to your actual position, 90 degrees perpendicular to the road. Clearly, geocaching requires knowing where you ARE, not where you might be on the nearest road. Until you wander quite far away from the road (I’d guess 150’ or more for most models), your coordinates are NOT indicative of your actual position. This was true all the way up through TomTom firmware versions 8.XXX.

[FONT=&quot]Many older TomTom models do not support firmware beyond some version at 8.XXX. As explained abnove, firmware that old or older displays the "road snapped" coordinates, not the real coordinates, on the satellite page. It is for that reason that his particular TomTom is nearly impossible to use for most urban caches and a lot of others as well. It will show his position at 90 degrees to the nearest road until he gets quite FAR from the road and the TomTom gives up trying to snap him to the nearest road position.

I and others complained that if a person were actually reading raw coordinate data from the satellite page as opposed to looking at a map, what they wanted was the REAL coordinate data, not some tweaked set of numbers that represented an alternate position on some road nearby. We told them many times, “Road Snap is fine for the map display, but don't ever lie about the latitude and longitude!”

I don't know if TomTom heard our complaints in this regard or simply thought better of their previous approach to coordinates, but with the advent of version 9.XXX firmware, the lat/long coordinates data on the satellite page are TRUE, not road-snapped coordinates. TomTom units released since 2009 have either come with 9.XXX firmware as shipped, or for the most part can be updated to newer 9.XXX firmware from their original 8.XXX firmware. However you get there, if you can, 9.XXX provides real latitude and longitude data.

For geocaching purposes, you'll need to set your TomTom's coordinate display (adjusted from the "Configure" button on the "GPS Status" satellite page) to the "Minutes (d?m.m')" (which gives you dd mm.mmm display) format that matches the posted coordinate format for geocaches. As I recall, that is not the default format for any TomTom model and will require that you configure this accordingly.

Those attempting to untether from the car and take a 9.XXX TomTom into the field to actually find a cache won’t find it as easy as with a decent handheld, even with real coordinate data. You'll have to keep your sense of N/S/E/W while you keep watch on the up/down ticking of the coordinate data on the display. A rough guide to distance in our part of the world is as follows:

For every 0.001 N/S difference between where you're standing and the cache coordinates, you're going to need to move another 6' or so. For example, if your latitude shows 40?01.335 and the cache is located at 40?01.340, you need to move 5 x 6' (about 30') further north.

For every 0.001 E/W difference between where you're standing and the cache coordinates, you're going to need to move another 4' or so. For example, if your longitude shows 104?59.520 and the cache is located at 104?59.540, you need to move 20 x 4' (about 80') further west.

OK - some obvious issues. Your TomTom is NOT water resistant, much less waterproof. It's NOT a purpose built handheld for backcountry use. Do NOT drop it in the drink. It’s not ruggedized, so don’t drop it PERIOD. Further, your TomTom has nowhere near the battery capacity of a decent handheld. If you get a couple of hours out of it between charges, consider yourself lucky. Time can be extended through the use of external USB 'power boosters' like this one Amazon.com: New Trent Super-pack IMP500 5000mAh External Battery pack for 3G iPad, iPhone 4 4G, iPhone 3G 3GS, iPod Touch (1G 2G 3G), Motorola Droid , HTC Android Phones, Blackberry (curve, bold, tour, storm) Brand new: Electronics that will give you almost 4X additional run time. However, if you own any of the newer GO series (e.g., the GO740 or later) there isn't a simple USB/USB connection.[/FONT]

 

[gatorguy]

Canderson, correct the spelling in the thread title and make this a sticky! Very nice. (Still easier with a nuvi tho, and feel free to edit out this comment before "sticking" )

 

[canderson]

Canderson, correct the spelling in the thread title and make this a sticky! Very nice. (Still easier with a nuvi tho, and feel free to edit out this comment before "sticking" )

If I "sticky" it, I'll just take the two major posts and start it up fresh.

The only Nuvi models that are actually easier to use for caching than a TomTom (apart from the fact that they'll take a *.gpx directly without the *.ov2 conversion) are the 500 and 550. Those really are more hybrid units, and almost usable in the field as well as the car. Trying to use ANY automotive GPS in lieu of a purpose-built handheld is going to be a serious compromise, as is trying to use a handheld unit as an automotive GPS (largely an issue of screen size, even if you have the very rare unit that gives audible directions instead of a simple "beep" to let you know you've got to so something). I still recommend that anyone serious about caching own one of each.

 

[gatorguy]

I disagree with part of your last post. Iif I enter coordinates for a cache in a park, I don't get "No Route Found" on a nuvi like I will with a TomTom. It will give me driving directions to the nearest road, and show a highlighted path from there to the off-road location. That seems easier to me. And with a (free) transparent map overlay of trails like I have on my nuvi, sometimes you can even see the walking path to the cache.

But a true handheld off-road navigator is a heckuva lot better as you said. And most of those will give you driving directions as well with the appropriate map.

 

[canderson]

I disagree with part of your last post. Iif I enter coordinates for a cache in a park, I don't get "No Route Found" on a nuvi like I will with a TomTom.

Need to look at that situation more carefully. I know full well it will happen if you mark a favorite far enough off-road or enter coordinates for such a position in a "Navigate To". But I've searched for a LOT of caches in large parks (esp. in the mountains), and for some reason, have never been "bounced" with a "No Route Found" by a POI that situated that way. My TomTom shows the route on-road for as far as it can, and then it just shows an arrow pointing off the road into the area that aims at the final location.

Since I load all of the caches to be found in a POI file, my TomTom has never given me that kind of grief, even when I use those POI points in an itinerary. So it's always been my impression that POI are treated better in this regard, and that's how the caches are being stored. What's your caching handle, BTW? I'm operating as ecanderson.

 

[dhn]

Corrected spelling in thread title and generalized about the TomTom model.