eTrex 20 vs Smartphone for trail groups

[eaparks]

In following all of your discussions here; from a long term trail managament perspective I would agree with the other recommendations to use a vector map / maps.
 
You could have a lot more flexibilty in managing the project/s.  You could have multiple maps with different information with all maps being transparent and enable each vector map as you desire.  One could be for topo (your 2 ft. contours or whatever), another for exisiting trails, and still another for future trails and view all of the maps at one time or disable any map you didn't want to see.  By using a custom .typ file you can get creative on the colors and look of the various trails by difficulty, property boundaries, one way trails, or any other distinguisable ideas AND ALL Garmin GPS that one can put maps on can utilize your maps.
 
The raster map/s would limit you for future expansion as the map gets more and more complicated.

[PHeller]

The ability to turn on and off layers is pretty cool.

Because I experimented with GPSMapEdit only briefly, I never utilized the ability to display different features with different patterns or colors.

Sounds like your saying I need to download GPSMapEdit again and learn how to use that program.

[Boyd]

Note that GarminDNR (I think MNDNR is just a variant on this) doesn't really make "maps". AFAIK, it just creates .gpx files. These files can contain routes, tracks and waypoints - point and line features in other words, but not polygons. Garmin vector maps are .img files and have much, much greater capabilities.

The raster based "custom maps" may work fine for you. Just keep in mind the limitations I mentioned above. Their size is very limited. For example, using one foot per pixel source imagery, you can only cover an area about 2 miles x 2 miles. At 10 feet per pixel, you can cover 20 miles x 20 miles and so forth. That resolution is well suited to a USGS 24k topo map for example. Maps covering an area much larger than this are going to look pretty crude when you zoom in.

[Seldom]

Their size is very limited. For example, using one foot per pixel source imagery, you can only cover an area about 2 miles x 2 miles. At 10 feet per pixel, you can cover 20 miles x 20 miles and so forth. That resolution is well suited to a USGS 24k topo map for example. Maps covering an area much larger than this are going to look pretty crude when you zoom in.

10 feet per pixel is probably OK for a 24k topo DRG, but you'd need to get down to 2 feet per pixel or smaller to resolve a 3 foot wide bike path or sidewalk on an orthophoto.

[Seldom]

Sounds like your saying I need to download GPSMapEdit again and learn how to use that program.

The nice thing about GPSmapedit is that it does a lot and doesn't cost much.  The not so nice thing is that there's no manual, so to learn how to use it you are restricted to third party tutorials and experimenting with the menus and buttons.

[Boyd]

If you want to make high resolution vector trail maps, you may run up against the limits of Garmin's 24 bit coordinate format. I brought this up here: http://forums.gpsfiledepot.com/index.php/topic,1335.msg8387.html#msg8387

I found that a raster based map was a better solution for the project described in that thread, as raster imagery doesn't have the 24 bit coordinate limit. But the area I was mapping was quite small.

[PHeller]

Boyd, would the smaller eTrex even be able to display at high resolution? Or would it require it more so?

[Boyd]

There would be no difference between the way the new eTrex or Oregon handle map files (both raster and vector). The Oregon has a higher resolution screen (400x240 vs 240x160 on the eTrex), so you would see more of the map on the Oregon and need to pan around on the eTrex to see the same area. But the way the files are interpreted would be the same.