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Maps & GPSs

How maps and GPS data are used in Mountain Meanders.  
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NB Mountain Meanders does not assume a user has a GPS unit and a GPS is not necessary for navigation

The information below is relevant to both GPS and non-GPS users and explains how routes are marked on both paper and GPS maps. 

With the increasing availability of GPS's,  in cell phones as well as in dedicated GPSs, GPS use is becoming more common although still not widespread.  So although a GPS is not needed, those with a unit will find a range of resources available which can add interest to the mountain experience.  (Navigation is only one of many GPS uses, and not necessarily the most important!).  Those interested in finding out more may like to read "
GPSs in the mountains – the good, the bad and the ugly 

Using a GPS and mapping software, can be simple and easy ... or complicated! The simple and easy which many GPS users stick to is to simply keep a record of the walks they have done and possibly display on one or other map.  Mountain Meanders has 'meandered' over the years the site has been under construction using a number of different GPS units and mapping software.  The notes below capture some of this experience, but potential GPS users should not be put off by this apparent complexity.  KISS is a good approach! 

Dedicated GPS vs Smart Phone?  The availability of GPS receivers in smart phones is rapidly changing the GPS and mapping environment. Just as smartphone cameras are making many stand alone cameras obsolete, so are GPS enabled smartphones making dedicated GPS units obsolete.  From a hiking perspective, the main drawback of smartphone based GPSs is limited battery life. GPS use drains smartphone batteries and few can operate for more than 8-10 hours while tracking vs many days with a dedicated GPS unit.  Besides lower cost, the other advantages of smartphones are: bigger, higher resolution screens, better maps for free and ease of sharing tracks. 

Dedicated GPS vs Smart Phone performance.  Preliminary tests with a limited range of smartphones has shown quite a high variability in performance compared to a dedicated GPS like a Garmin. There generally tends to be more jitter, especially in difficult terrain (ravines, trees, south facing slopes, etc), but given that the GPS functionality effectively comes for free as part of a smartphone, it's hard to complain.  Unless one is a (wealthy) perfectionist (or need the longer battery life) it would be hard to justify the outlay on a dedicated GPS.  If you have one, keep it, but if not don't bother.  Smartphone GPSs will also undoubtedly get rapidly better.  

Android mapping: On an Android phone, one particular application stands out.  It is the Open Source Street maps (OsmAnd) and the associated Contour Line plug in. This provides detailed off-line street  and contour maps of the entire world for $2 (yes, that is two US dollars!!) It is an amazing resource, better than Garmin maps and better than Google Maps because it works off-line (after downloading) and hence can be used where there is no cell reception and incurring no data charges. OsmAnd is particularly good for Table Mountain and the Peninsular as, unlike Garmin maps, it already has most major (and many minor) paths marked.  Furthermore, the paths are apparently routable. (Not tested and and not recommended - use at own risk!) 

Maps: Two kinds of maps are usually provided, one for those who don't have a GPS or mapping software, and one for those who do.  The former are in either Adobe pdf or jpg (picture) files which can be downloaded and printed.   Those who have mapping software may prefer to download the GPS tracks and make their own maps.

Open Source Maps (OSM): OSM Street Maps provide a potentially useful resource as additional tracks can be added easily, especially if combined with a transparent contour set such as that available from MadMappers.  The OSM maps are available in Garmin format from http://garmin.openstreetmap.nl

Track and route marking: A major problem with Garmin Mapsource is that it has very limited track drawing capability. A solid black line or ugly thick coloured lines is all it can manage. The successor to Mapsource, Basecamp, is better, but still limited. One function where Basecamp excels is producing printed maps of an area to any scale and size up to A0 size on an ordinary A4 printer by tiling.  It automatically provides accurate tile alignment and overlaps so that all it needs is a simple trim and paste to create a large format map. The fixed 1:50 000 scale of the SA Topographical maps is inadequate for many mountain uses. 1:20 000, 1:10 000 or even 1:5 000 are much easier to use. Importantly, Basecamp provides the ability to produce a map at whatever scale is necessary or desired.  

Although tools exist to draw better maps, they are complex or expensive... or both.  Recently (2010) a neat package has been released called gpx2img which converts gpx (or Garmin gdb) files into a transparent Garmin img file which can be loaded into Mapsource or Basecamp and a GPS.  At the same time, the style of a track can be changed so that dashed and dotted lines can be used.  (Lines could also be coloured but these do not transfer well across different print, screen and GPS media, so simple black lines seem better, especially as colour printers are not in common use.)

The following notation is used: 

 Map  Description  Likely grades
 Jeep track or major path e.g pipe track  0 
 Defined path  0, 1 and 2
 Scrambling route or off-path  2, 3, 4 and 5

(0)  Jeep track, contour path
(1)  Walk
(2)  Easy scramble
(3)  Moderate scramble
(4)  Difficult scramble
(5)  Rock climb
Marking of grading on maps:  The grade in () is used on maps to mark the grade in situ. (This is work in progress - not widely implemented yet.)  This has overcome a concern that, by marking scrambling routes on a map, a user may assume it is an easy path.  Making the grade directly visible reduces this risk.  Long routes can also be marked at a number of points, or the approach can be marked with a different grade if this links up with another route, etc.  All in all this has proved very useful and solved a number of problems. 

         Note: The conversion of maps to use this notation is in progress (as of April 2011) and will take some time.... any volunteers? 

        You can also create your own maps using gpx2img and use the TYP file available here to convert tracks to the dashed and dotted formats. (It is not automatic - some manual editing is required, but it is easy.)  One small current problem with gpx2img is that it adds labels to all waypoints and tracks.  The developer has undertaken to release a new version "soon" (May 2011?)  that adds a flag to turn these on and off.  Not a problem on a small area, but results in a lot of clutter on a big area like all of TM. (It is only in Mapsource that this is a problem - in the GPS labels can be turned on or off.)

To display the map produced by gps2img together with any other Mapsource map (for example to overlay the tracks on the SA Topographical) a second step is needed.  MapSetToolKit is one tool for doing this. (See also Free Geography Tools and Maps 'n Trails for more information.) Looks a bit intimidating, but it manages all the complex stuff remarkably easily. MapSetToolKit is also an excellent tool for managing mapsets in Mapsource or Basecamp which are otherwise "black boxes". 

PS The reason for using the [A], [B], etc route name notation is so that the routes stay sorted "geographically" rather than alphabetically.  It is also a help for organising all the data that underpins Mountain Meanders. 

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CustomWaypointSymbols.zip
(26k)
Tony Heher,
Apr 4, 2011, 5:15 AM
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Dash4.typ
(1k)
Tony Heher,
Apr 4, 2011, 4:57 AM
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