Results 1 to 18 of 18

Thread: A short GPS Primer

Threaded View

Previous Post Previous Post   Next Post Next Post
  1. #1
    Senior Member Farmsky's Avatar
    Join Date
    Jan 2008
    Location
    Gloucester, NSW
    Posts
    964
    Thanks
    138
    Thanked 193 Times in 85 Posts
    Rep Power
    253
    Reputation
    1181

    Default A short GPS Primer

    This information is littered with 'my opinions' on certain subjects and products. Reader beware

    - - - - - - - - -

    There are two fundamental forms of GPS mapping systems.

    Vector maps

    All street navigators use vector mapping. The streets, roads and landforms etc are encoded in software as points, lines, and polygons stored and displayed using their mathematical constructs. The advantage is that the map data (stored in memory or on SD card) is relatively small and the resulting image is crystal clear at any zoom level. As the zoom level is increased or decreased, map features are 'added or removed' automatically, so that screen clutter is managed. Map pre and post planning may be supported (depending on the product) via PC software. Vector maps may be routable ie they can be programmed to provide directions with 'turn by voice' directions.

    Navteq or Sensis?

    Australian vector mapping and poi data is produced by either 'Sensis' or 'Navteq'. The main GPS players; Garmin, TomTom and Navman use Sensis .... for a good reason. Sensis is the most accurate and up to date dataset; with better speed and lane information etc in the Cities, highways and rural areas. Navteq is claimed (by some) to have a better rural dataset. I have my doubts, however in all fairness they both have particular strengths and weaknesses. Navteq is the 'cheaper' map used by the low volume suppliers such as Navigon (it's an excellent street navigator btw) and the 'all so rans' such as R66 etc.

    City street navigation vector maps are generally useless in the real bush. TomTom, Garmin, Mio, Navman, Navteq or Sensis, it makes no difference, they're all as good and bad as each other.

    If you're up the Strzelecki .... you need an 'off road map'. Purpose made Australian off road topographical vector maps are currently available for Garmin and Magellan GPS's. Read more further on.

    As Garmin's mapping format is open source, anyone can build a Garmin map. Now that's good news. A number of countries, with enthusiast support, have developed sophisticated free auto-routing Garmin maps. Singapore and New Zealand have developed leading edge free Garmin turn by voice vector maps.

    However for most soft roaders, a standard issue street vector map will do the job just fine.

    Raster maps

    Many off road navigators deploy raster maps. The major raster mapping softwares used in Aussie are Oziexplorer (PC and car mount variants) as used by the Hema Navigator and MemoryMap. The VMS tourer uses a variant of MemoryMap call iTopo. iTopo uses proprietary map encoding. A one off license of around $100 is required to convert maps to MemoryMap format.

    Raster maps are simply an image of a paper map. They are viewed on screen as a moving map image. They are best viewed at only one zoom level for the sharpest image. Raster maps are not routable. You can create routable tracks of your own.

    However anyone can make a raster map, so the mapping database is huge. 1:25k mapping (or better) where available, will give the very best track information and details. The full Hema paper mapping series is available in digital form.

    There are many free and commercial sources of quality raster mapping.

    Many consider Des Newman's (PC version) and OziCe (PNA/PND version) to be the king of commercial raster GPS software. There are competitors (CompeGPS, Memorymap, Fugawi etc), however IMO Ozi is consistently the most featured and versatile of all.

    Garmin

    As mentioned above, the beauty of Garmin over other GPS street navigators is that the map software is open source. That means that 3rd parties can produce Garmin compatible maps. Australian purchased, street navigation Garmins, come standard with Garmins City Navigator 2009 (new maps have just been released). City Navigator is a Sensis mapping product, which is excellent for towns and cities. No good in the bush though as noted above.

    Oztopo and Garmin Topo are the two commercial mapsets that will take you off-road with a Garmin. Garmin Topo is 1:100,000 map based with fixed 20m contours and is auto routing for remote tracks. Nice, however you cannot turn contours off, which may make the screen a bit busy at times. 10m contours, (and the ability to turn contours on and off to make maps easier to read - two mapsets) and 1:25,000 topo map detail makes OzTopo the current vector off road favourite for many. However it is not auto routing.

    Shonky Maps is a wonderful (not auto routing) free mapset for all of Australia based on Natmap 250k data. Dooghan's Contours v2.0 is a free transparent overlay giving 10m contours for all of Aussie. You can meet them on this forum from time to time.

    The Open Street Map ( ) project (enthusiasts like you and me) is slowly but surely mapping Australia and this is providing . More .

    Hint: You'll need Mapsource so read a bit further on.

    Garmin screens are nice and bright!

    So there are a few good reasons to buy Garmin.

    Marine, Handheld, Bush walking and Geocaching GPS

    This surprisingly, is a quite a spec_ialist area. Best to bone up and ask questions of the many expert enthusiasts here.

    One street navigator perhaps worth a look at in this category (long battery life and waterproof) is the Garmin Nuvi 500.

    Cross-over GPS's

    These units run both vector and raster mapping software and maps. Brief information on a short selection of these units follows.

    Chinese imported PNA's/ PND's will generally perform a cross-over function, as access to the WinCe operating system is straightforward; enabling access to the operation of raster GPS software.

    Hema Navigator

    Not in your life. The street mapping software is Route 66. It uses (cheap) Navteq mapping and the GPS engine is simply horrible.

    The off-road mapping uses a version of OziexplorerCE. It is excellent.

    VMS Touring

    Well worth a look. It uses the excellent iGO8 street mapping software and Sensis mapping.

    The off-road (raster map based) navigator, iTopo is considered a more intuitive system than OziExplorer for a beginner.

    The VMS product can be purchased with an AV input for a rear view camera. Sweet!

    Magellan Crossover

    I'm no expert on Magellan GPS. You can purchase off-road Magellan topo mapping (vector format and said to be the very best topo map currently available) so that's a big plus, and like Garmin Topo it's Navteq based. 8 hour hand held, 'out of the car' battery life is a bonus.

    CompeGPS TwoNav

    Long awaited but it's on it's way and it promising big things for a little bundle.

    And lastly TomTom with ttMap

    Yup TomTom's gone raster. Check it out and on this forum.

    Garmins Mapsource

    IF you have a Garmin ... almost any Garmin street or handheld navigator .... or even if you don't; here's how to get hold of some nice free topographical maps for outback trip planning.

    1. Download and install Garmin's Mapsource. how. It's free and legal. You can now view Garmin maps on your PC. Download and install if you want moving Garmin maps on your laptop in conjunction with your GPS or GPS mouse.

    2. Download free Garmin topographical maps of Australia. some more info. It's a big download so best to use a download manager to ensure a corruption free download.

    You can plan and develop your own routes, tracks and waypoints in Mapsource for upload to your GPS.

    Mac users are not forgotten. Garmin's (free) will help you with maps and tracks 'n thing. Review . After that review, I'm still confused, but then it's probably a Mac thing.

    And there's now a free 5m (yes 5m!) transparent 'contour only' map available Contours 3.0 and . Thanks Dooghan.

    Shonky is great in the Aussie bush, but there is little detail in towns and cities. The OSM project is slowly mapping Australia and is very very good for many city and town areas; not so good in the bush. Routable are now available. Have a and see if your area is mapped. If not why not do some mapping.

    To load these great maps and contours to your GPS via Mapsource have a look at this .

    Note: If you only need Shonky maps, a quick and dirty solution is to download the ready made version (there's no need to fiddle with Mapsource). Get hold of an SD card, create a folder in the root of the SD card called Garmin and place (gmapsupp.img) in there. Shonky 'gmapsupp.img' is a 413.95 Mb download (434,061,312 bytes).

    Other Free Stuff

    a fulsome list of the many free GPS applications available

    Moving maps on your lappie

    Yeah the big screen! nRoute (free) enables moving map (and turn by voice directions with suitable maps) via your laptop or netbook coupled to a suitable GPS. nRoute works readily with your handheld Garmin GPS (not a Nuvi), however you will require an emulator if your GPS device is non Garmin. There's good info in the forums on how to achieve this. is the latest commercial offering augmenting the older but free nRoute. Unfortunately, to date there is no Ausssie offering. OziExplorer is probably the best option for raster maps.

    - - - -

    Note: The downloads are quite large, so the use of a to ensure complete, error free downloads is highly recommended; 'Down Them All (Firefox)', Download Express, Free Download manager etc.

    Now that lot'll keep you quite busy till tea time.

    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    Note: This is a quick off the top of my head primer.

    If I have missed key info, data or products it was unintentional.
    Last edited by Farmsky; 01-09-09 at 07:09 PM. Reason: added ttMaps :)

  2. The Following 19 Users Say Thank You to Farmsky For This Useful Post:

    + Show/Hide list of the thanked

    bazzle01 (22-11-11),bigfella08 (01-12-09),Coldamus (05-11-10),covert (22-10-09),Fernbay (01-09-09),hollowman (02-12-09),hyundai (19-08-12),Jards88 (18-09-09),jba_driver (30-06-10),jimmyc (26-05-12),johnno02 (14-12-09),jonnyath (04-08-12),phoenix (20-10-09),randersn (03-02-10),snibs (01-09-09),timbo43 (08-05-10),Triggy (10-04-10),tristen (29-10-09)

  3. Look Here ->

Similar Threads

  1. ASUS F5R Laptop with short battery life
    By JK200SX in forum PC Hardware and Printers (including 3D Printers)
    Replies: 4
    Last Post: 26-06-16, 07:55 PM
  2. TT Cut Short Report
    By ATTITUDE in forum General Chat
    Replies: 2
    Last Post: 29-06-09, 08:09 PM
  3. Tall Meets Short
    By Conor in forum General Chat
    Replies: 0
    Last Post: 13-04-09, 09:10 PM
  4. Red Bull short film
    By rosekelin in forum Introduce Yourself
    Replies: 1
    Last Post: 01-08-08, 12:16 PM
  5. WTB: Somone to do a short 15 Second Flash Animation
    By urban_s0ulja in forum Buy Sell and Trade
    Replies: 3
    Last Post: 22-06-08, 03:28 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •