What's the difference between obtaining free map here vs purchase online

[patrick17th]

I'm about to buy the new etrex 20x GPS device, primarily to play geocaching with my family (the best way to convince my kids that hiking is fun when looking for "buried treasure")

We just moved to Colorado few months ago, there's so much to see outdoor that we should be taking advantage of. Been researching on which device suits us the best then learned that maps are not preloaded on devices. We need to either download from GPSFileDepot or purchase the Micro SD card that already have preloaded map of certain region on it. The one I wanted is Colorado and it comes with Utah, its called "Garmin TOPO US 24K Colorado/Utah" and it cost $80.

My question here is what's the difference between the one I can download from here for free vs the one that I need to pay for?

[Boyd]

That is sort of like asking "what's the difference between home movies and Hollywood films".

The maps here are made by people as a hobby (I am one of them). The best of them will have some special feature that makes them stand out. Then there are many which have just been put together by formula from the same sources, using the tutorials on this site. Nothing wrong with that of course. Many of these are excellent and will be all that many people need.

To dig a little deeper, Garmin considers their map format proprietary and they have never officially published the specifics. They have special software to create their maps and they guard it very closely. It is not available to people outside their own network. So all the free maps here and elsewhere were created with reverse-engineered tools. These tools are far behind Garmin's proprietary tools. The author of the software used for most of the maps here ceased development of his program a number of years ago.

Garmin topo maps have elevation data (DEM) that will generate shaded 3d views and no third party maps can do this. Garmin's 24k topo maps also have routable roads that can give you turn by turn directions. It's possible for a third party map to provide this, but only a few of the thousands of maps here can do this because it invloves a lot of work.

Garmin 24k topo maps also have a rich set of POI's - things like restaurants, gas stations, stores, etc. They have to resources to purchase this data and the time to compile it into the map. None of the maps here have that kind of detail.

But the good thing is, the maps here are FREE. So what do you have to lose? Just download whatever looks interesting and give it a try. If you like it, don't look back and just get out and enjoy yourself!

If you do purchase a Garmin map, get the DVD version if possible. Garmin seems to be discontinuing these. But there are some big differences. They are more expensive, however if you actually compare them with the download and memory card versions, you will see the DVD version covers more states. But the big difference is, there are no restrictions on using the DVD maps, so you can install on all the GPS devices you own. You can also make backup copies to protect you investment.

The preloaded cards can be used in any gps, but they cannot be duplicated. They will only work on the original card, so if anything happens to that, you're just out of luck.

The download version give a little more safety because you can download them again if needed for 12 months following purchase. You can also make backup copies and they are not tied to single data card. However, they will be permanently tied to the gps they were purchased for. So if you decide to sell your GPS in a few years, you would not be able to install this map on your new GPS.

[Boyd]

Sorry if I got a little long winded there.

In making a decision, probably your first question should be whether you want a routable topo map. Most of the maps here are not routable. This means you will see your position on the screen but the gps can't give you walking or driving directions. You can select a destination, but the GPS will just draw a straight line to it from your current position.

Garmin's 24k topo series has routable roads, but their 100k topo does not.

[patrick17th]

Boyd, you made beautiful points here based on the difference between the maps found here vs buying through Garmin's product maps. As you said, its free here so I have nothing to lose here by trying it out and if it doesn't suit my needs that well, then I know the next necessary step to take 

I've just ordered the etrex 20x model this morning roughly after posting my first message here. Will be receiving it in couple of days from GPS City site in time to enjoy the spring break with kids navigating.

Thanks again for the specular explanations. 

[Boyd]

Glad I could help.

[Christian_Sky]

Patrick17th, thank you, as you saved me from starting a new thread because like you, I'm new to this and like you, I was wondering which maps would be good for the state of Utah. Boyd, great feedback. Thank you as well. I'm actually ordering the etrex 35 specifically for use during an upcoming trip to Moab, Utah, where I plan on spending time within the national parks both on foot and off road in a Jeep. By the sounds of it, the Garmin 24k topo Colorodo/Utah map may suit my needs. And I'll apologize in advance, Boyd, if you have answered this question many times...but with the Garmin 24k map I would assume since it is routable that I can plug in way points to say, find my way back during an extended hike. My question would be if when you say that most of the maps on this site are not routable, do you also mean that one would not be able to mark way points on these particular maps? I plan on doing some late night photography on some off the beaten path places and I just want to be able to basically retrace my path back. I'm wondering if these non routable maps would allow me to do that. If so, then I may just forgo purchasing the Garmin 24k Colorado/Utah topo.

[Boyd]

The GPS can use several different kinds of data. You might consider a map "system data". Then there's "user data" which consists of waypoints that you mark yourself and tracks that you record yourself. These can be done out on the trail, or in advance on either the computer or gps itself.

System data and user data are completely different things, and they exist separately. So you can use your waypoints and tracks on any map. Or you can even use them with no map at all. If you have no map or if the map isn't routable, the gps can guide you on routes in straight lines between waypoints. If the map is routable AND IF THE ROAD/TRAIL IS ON THE MAP, then the gps can give you turn by turn directions to follow the road or trail.

Now if you hike off-road to take pictures and you record your track, you will see it on the gps screen. This works with any map, and also works with no map at all. You could visually follow that line back to your car then, since your current position is always shown on screen.

Newer Garmin models like the eTrex have an "advanced track navigation" feature that lets a recorded track be used like a routable road/trail too. Here's some info on that: http://gpstracklog.com/2010/07/navigating-tracks-on-the-new-garmin-handhelds.html

[Christian_Sky]

Thanks, Boyd! Your feedback will be very helpful. Cheers.