How to Use OziExplorer with Digital Maps and GPS DevicesOziExplorer is a powerful desktop mapping program that lets hikers, surveyors, field workers, and outdoor enthusiasts view, manage, and navigate using raster maps (scanned or downloaded) together with GPS track and waypoint data. This guide explains how to prepare digital maps, calibrate them in OziExplorer, connect and use GPS devices, plan routes, and troubleshoot common problems.
1. What OziExplorer does and when to use it
OziExplorer displays raster maps (TIFF, JPG, PNG, etc.) and overlays GPS tracks, waypoints, and routes in real time. Use it when you have:
- Custom or scanned topographic maps not available as standard online maps.
- Specialized maps (hunting maps, forestry maps, paper-to-digital conversions).
- A need to store, edit, and analyze GPS tracks on a PC.
Key strengths: supports many GPS formats, detailed map calibration, extensive waypoint/route editing, and export/import options.
2. Preparing digital maps
- Choose map images: scan paper maps at 300–600 dpi or download high-resolution images (TIFF, PNG, JPG). Prefer lossless formats (TIFF/PNG) for best quality.
- Crop and clean images: remove scanner borders and improve contrast/brightness if necessary using an image editor (GIMP, Photoshop).
- Reduce file size (if huge): split large maps into tiles or downsample slightly—keep enough resolution for your intended zoom level.
Tip: Keep both an original high-resolution file and a working copy for calibration.
3. Calibrating maps in OziExplorer
Calibration (georeferencing) tells OziExplorer how map pixels correspond to real-world coordinates.
Steps:
- Open OziExplorer and create a new map (File → Load Image → choose your map).
- Add calibration points (control points): click a recognizable location on the map image, then enter its real-world coordinates (latitude/longitude or UTM). You can type coordinates manually, pick from a GPX/KML file, or use a GPS fix.
- Use at least three well-spread control points; more points improve accuracy and allow for higher-order transformations.
- Choose a map projection: if your coordinates are lat/lon, use geographic; for UTM coordinates, choose UTM and the correct zone.
- Save the calibration with a matching .map file (OziExplorer creates associated files storing calibration and settings).
Practical tips:
- Pick control points far apart and near corners of the map to reduce distortion.
- If you have grid or tick marks on the original map (latitude/longitude or UTM grid), use them for precise points.
- After placing points, check the residual error for each control point and adjust if any are outliers.
4. Loading and organizing maps (map sets)
- Create Map Sets to group tiles/adjacent map images into a single navigable area (maps → Map Sets → Create). This lets you pan seamlessly between adjacent images.
- Use consistent naming and folder structure: keep images and their .map files together.
- Use the MapInfo fields to add metadata (scale, source, date).
5. Connecting a GPS device
OziExplorer supports many GPS receivers via serial (COM), Bluetooth virtual COM, or USB (drivers create a COM port). It also imports GPX/NMEA files.
Steps to connect:
- Connect your GPS to the PC and note the COM port number (Device Manager on Windows).
- In OziExplorer, go to Configure → Communication → GPS and set the COM port and baud rate (common rates: 4800, 9600, 38400; check your device manual).
- Choose the GPS protocol if required (NMEA, Garmin, etc.). Auto-detect may work.
- Click Connect; OziExplorer should begin receiving position fixes, showing your real-time location on the map.
Troubleshooting:
- No data: check COM port, cable/driver, and correct baud rate.
- Garbled data: wrong baud or protocol.
- Bluetooth: ensure the GPS is paired and assigned a COM port.
6. Displaying and using GPS data
- Live position: OziExplorer shows current position as an icon; configure update rate in settings.
- Tracks: record tracks from the GPS to OziExplorer (File → GPS → Receive Tracks) or let the device record and import later.
- Waypoints and routes: send and receive via File → GPS → Send/Receive Waypoints/Routes. Use formats supported by your device.
Practical usage:
- Follow a route by loading it in OziExplorer and using the “Follow GPS” mode; the map centers on your position and optionally rotates.
- Use the “Go To” feature to navigate to a waypoint; OziExplorer calculates distance and bearing.
- Save GPS logs as .log, .plt, or GPX for import into other tools.
7. Planning routes and analyzing tracks
- Create waypoints interactively: right-click on the map → Add Waypoint; edit coordinates and properties.
- Build routes by ordering waypoints; save as .wpt/.rte or export to GPX for your GPS.
- Analyze tracks: view speed, ascent/descent, distance statistics; export for further analysis.
Examples of export formats: GPX, KML, CSV, Ozi’s native formats (.plt, .wpt, .map).
8. Advanced features
- Geo-referencing with higher-order polynomials: useful if the source map has distortions.
- Map rotation and scaling: align maps more precisely when scanned skewed.
- Map calibration using online georeference services: import known coordinates from Google Maps or other sources if permitted.
- Batch calibration and scripting: for users processing many map tiles.
9. Common problems and fixes
- Map misalignment: add more control points, especially near problem areas; check projection settings.
- Poor GPS reception: ensure antenna has clear sky view; try increasing update interval or logging on the device.
- Large map performance: use tiled maps or reduce image resolution for smoother performance.
- Incorrect units: verify projection/coordinate system (lat/lon vs UTM) and units (degrees vs meters).
10. Example workflow (step-by-step)
- Scan map at 300 dpi and save as TIFF.
- Load TIFF into OziExplorer.
- Add at least 4 control points using known lat/lon coordinates from benchmark points or GPS.
- Save the .map calibration file.
- Create a Map Set if the map covers one tile of a larger area.
- Connect GPS via COM port, set protocol and baud, click Connect.
- Record track while you navigate and add waypoints as needed.
- Export recorded track to GPX and analyze in other software or share.
11. Resources and next steps
- Consult your GPS device manual for correct COM/baud and protocol settings.
- Back up original scans and .map files.
- Practice calibrating small maps to gain confidence before committing large map sets.
If you want, I can: calibrate a specific map image if you provide it and three known coordinates, create a sample route from two points you give, or provide step-by-step screenshots for a particular GPS model.
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