Creating Garmin Custom Maps in Five Easy Steps

Despite the growing breadth of maps designed specifically for outdoor handhelds, sometimes the best map for a specific activity is only available in printed form or as a PDF or JPG file.  Running the latest beta software releases for Garmin Colorado, Oregon ( 200, 300, 400 and 550), and Dakota devices, using paper maps with Garmin outdoor handhelds is easier than ever with Garmin Custom Maps.  This unique feature allows users to combine Garmin map drawing technology with georeferenced map images, effectively putting a paper map inside your Garmin GPS.  Creating a Garmin Custom Map for your Colorado, Oregon, or Dakota device is easy with the following steps. However, please be responsible and only create a Garmin Custom Map from a map that is in the public domain, you holdthe copyright in, or you have permission to use from the copyright holder.

Step 1: Save the map in JPG format
Begin with the map you wish to use on your Garmin device.  If in printed form, scan the image at an appropriate resolution (Oregon & Colorado have a native solution of 155 dpi).  Garmin Custom Maps require the map be saved in JPG format. Since many maps are available in PDF, they may require conversion using GIMP or other suitable program.

Step 2: Create an Image Overlay
Using Google Earth to georeference your map, begin by locating the approximate area on Earth where your Garmin Custom Map will be located.  The closer the viewing window is to the location and coverage area of your JPG, the easier it will be to georeference. Once the location is set in Google Earth, use the menu to select “Add”, then select “Image Overlay”.

Step 3: Link the JPG
In the dialog box that follows, three important fields should be completed:
• Provide a meaningful Name. 
• Set the Link field to the path of the source JPG to georeference.
• On the Location tab, Draw Order can be adjusted if desired.  Draw order values less than 50 places the Garmin Custom Map below roads & trails, values 50 and greater places the Garmin Custom Map above most map features except points of interest & waypoints.

Step 4: Adjust the Boundaries
Before closing the New Image Overlay dialog box, you need to georeference the JPG.  The most common way to do this is adjust the green marks to adjust the corners (a), edges (b), center (c), or rotation (d) of the JPG so it matches the satellite imagery beneath.  It may be necessary to adjust the transparency (in the New Image Overlay dialog) to a level that allows adequate viewing of the JPG and imagery beneath.  Once you are satisfied with the alignment of the source material, select “OK” on the New Image Overlay dialog box.

Step 5: Send to Garmin
To send the newly created Garmin Custom Map to your Colorado, Oregon, or Dakota it should be saved to the device.  To do this, right click on your Garmin Custom Map in the “Places” section on the left-hand side.  From the popup menu, select “Save Place As”.  Use the following dialog box to save your Garmin Custom Map to your Garmin handheld device, placing the file in the /Garmin/CustomMaps/ directory.  Be sure to save the file in the KMZ format.  If preferred, the file can be saved to a microSD card, in a /Garmin/CustomMaps/ directory for use with Garmin handhelds.

Once saved to the device, the Garmin Custom Map will appear as part of the map.  By default, Garmin Custom Maps are enabled on the device, but can be disabled under the Map Setup menu (select Map Information).

To discuss Garmin Custom Maps with others, please visit our Garmin Custom Maps developer forums.

 

Make the Perfect Handheld with Profiles

Garmin handheld customers often enjoy using their devices for multiple activities.  Many times, these activities utilize different features and require unique settings.  Imagine a customer wishing to use a Dakotato bike along roads with City Navigatordata but route direct to nearby geocaches.  Sometimes, multiple family members share a single GPS unit but each has preferences unique to how they use the device.    With the addition of profiles in Garmin Colorado, Oregon, and Dakota devices, switching between customized usage modes and individual users is easier than ever before.  These devices come preconfigured for common activity types (Geocaching, Fitness, Recreational, Marine, & Automotive).  Default profiles optimize settings and applications for the given activity.  Users can also easily edit or create profiles to customize everything from what maps are drawn to what applications are in the main menu.

 

Another great feature of Profiles is the current profile is constantly updated, so changes or preferences adjusted in the device are automatically stored with the profile.  There is no need to setup profiles, simply use the unit normally and set your current profile to your current activity (Geocaching, Fitness, etc.) or user (i.e. Brad, Tom, etc.). 

To create a new profile, select “Profiles” from the setup menu.  At the bottom of the list, select “<Create New Profile>”.  This will create a new profile (“Profile X”) and set it as the current profile.  From this point, any changes to the device setup will be associated with the new profile.  Be sure to give the profile a fitting name by selecting “Profile X” from the list of profiles, the select “Edit Name”.  Consider changing the background in display setup to easily recognize the current profile.

 

Never Lose a Track Point with Archived Tracks

Recording a tracklog is among the basic features available on every Garmin handheld.  Sometimes recorded tracklogs play critical roles in helping users TracBack® safely in challenging weather conditions.  Other times tracklogs may record the perimeter of a field (useful for calculating the area of the field).  For many users, a tracklog is simply a great way to record a memorable outing.

A common misconception is the necessity to record a point every second to generate the most accurate tracklog.  Unfortunately, this leads to significantly more points than necessary to represent adequately an activity.  Extra points typically provide no added benefit but reduce the recorded length of an outing and negatively impact device performance (such as map drawing, elevation profile plotting, and TracBack navigation).  For these reasons, Garmin encourages customers to utilize automatic tracklog recording.  Adjusting the interval (from Least Often to Most Often) allows users to adjust the granularity of recorded logs while ensuring the most representative points are retained. 

Even using our automatic recording method, users consistently request increased tracklog capacities, especially customers taking multiple-day excursions without access to their favorite desktop application to archive each day's tracklog.  In our eTrex and GPSMap 60 products, we also began allowing users to archive older trackpoints onto the memory card.  By reading the card (in mass storage mode or through a card reader), the archived trackpoints are available in GPX files.   To enable this feature, select Data Card Setup from the Track Setup page, then enable the Log Track To Data Card checkbox.  On these devices, users can create saved tracks, which filters active tracks to a small representative subset of trackpoints. 

Colorado, Oregon, and Dakota devices, have significantly more internal memory than previous generation devices.  This extra internal memory enables these units to store complete, unfiltered copies of the active tracklog for every saved track, an advancement over filtered saved tracks from previous devices.  The extra memory also allows automatic archiving of older trackpoints, providing users assurance that should the 10,000-point active tracklog fill completely, older trackpoints will be available for review when the device is connected to a computer (through mass storage mode).  To access archived trackpoints, look in the Garmin\GPX\Archive folder.

Managing Location Data with BaseCamp

After using a Garmin handheld for a period time, users realize value in the data collected by their devices.  Stored waypoints to mark important locations; collected track logs record hikes along scenic trails or perhaps property boundaries for surveyed land.   Still other users plan hikes and trips at their computer and send the location-related data to their handheld GPS for use during their excursion.

Garmin's BaseCamp application is designed specifically for handheld GPS enthusiasts.  Along with supporting our topographic content, BaseCamp interfaces with handheld Garmin GPS devices and manages location-based content to get the most from each device.  This free desktop application for PC and Mac is available for download and easily extracts waypoints, tracks, and routes from a GPS and organizes the data on the computer; BaseCamp even enables transferring data back to your GPS - simply select the information to send to the device and BaseCamp handles the transfer.

BaseCamp works with every Garmin handheld, but newer devices such as the Dakota series and Oregon 550 devices do even more with BaseCamp than previous products.  Earlier mass storage devices imported and exported routes, waypoints, tracks, and geocaches using a GPX file format. However, these newer products share the GPX files with programs like BaseCamp, allowing BaseCamp to edit or remove location data from Garmin GPS devices - two features previously difficult to achieve on desktop applications.

This new functionality is particularly useful because it allows users to collect data in the field, expand on the location data at a computer, and immediately benefit by having the changes reflected on the device.

APRS® Support in Colorado® and Oregon®

Of the digital modes in use by Amateur Radio operators, a popular one on 2m is the Automatic Packet Reporting System (APRS). This unique system allows users to exchange data about what is going on around them, including other users' positions, repeaters, weather stations, ham fests, hospitals, emergency operations centers, search and rescue teams, and more. To participate, most amateurs usually use three pieces of equipment: a radio, a TNC or tracker (a specialized TNC with specific support for APRS), and a GPS receiver with NMEA support. The Colorado and Oregonrequire a serial data/power cableto communicate with a tracker. For connection details, see the tracker's documentation. The interface mode on the GPS unit should be set to NMEA In/Out and waypoint output should be enabled on the tracker. After connecting the radio to the tracker and tuning it to 144.390MHz (the APRS frequency in North America), waypoints will start to appear on the Garmin handheld.

Seeing waypoints on a map presents a good spatial representation of people and objects relative to the device’s current position, but Garmin’s new Additional Waypoint Information NMEA sentence ($PGRMW) allows the tracker to update a waypoint's altitude, symbol and comment. In addition to a more effective visual presentation, waypoints (such as a training session) can now be updated with details that make them more useful (the date and time).

 

Currently, the Tracker2 from Argent Data Systems supports the $PGRMW sentence but we look forward to more device manufactures and hobbyists taking advantage of this added capability.

Further Reading: 
Garmin Proprietary NMEA 0183 Sentences Technical Specifications 

APRS is a registered trademark of Bob Bruninga, WB4APR

 

Waypoint Averaging

A common misconception of many outdoor GPS device users is they need to average every waypoint they mark.  However, modern advanced GPS chipsets do significant amounts of calculations and filtering before reporting a position, diminishing the benefits of short-term averaging.   For many waypoints (campsites, houses, trailheads, etc.), averaging is unnecessary because even in the most challenging GPS conditions, the waypoint will likely be within 30ft of the ground truth.  In some circumstances, such as saving a geocache location or marking a waypoint in dense tree cover, it is beneficial to gain additional confidence the marked location is as close to ground truth as possible.

We recently completed detailed research on various waypoint averaging techniques and their respective benefits.  Our research culminated in an improved multi-sample averaging technique which outperforms the traditional short-term averaging.  The first implementation offering the multi-sample technique is offered as a new application on our Oregon® platform.

Traditional Short-term averaging involves averaging a location over a few minutes.   This technique removes large temporary errors in GPS position and is most beneficial when conditions are challenging (such as dense tree cover) but can not mitigate errors from the current satellite constellation.  For best results in difficult conditions, our research found short-term averaging should be done for at least 5 minutes, preferably 7 to 10 minutes.  Oregon’s application indicates how long it recommends averaging based on current conditions.

Multi-sample averaging involves returning multiple times to collect short-term average samples, mitigating errors from the current satellite constellation and allowing a waypoint to converge to ground truth as additional samples are added.  For multi-sample averaging, our research uncovered two important factors in achieving the greatest error reduction: the number of samples collected and the elapsed time between samples.  For optimal results, at least 4-8 samples should be collected spaced at least 90 minutes apart (allowing the satellite constellation sufficient time to change).