Monday, September 11, 2006

Geotagging with the Magellan Explorist

If you read back when I start writing on GPS about a year and half ago, I didn't have in my mind the two basic functions one should look for in a GPS unit (back then I was distracted by moving maps, color and high res screens). Now I would look for:

  • battery longevity and
  • tracking capabilities

That’s it.

I told myself (and you) that I wasn’t going to learn another UI, I wanted to hang to some sort of common interface, for me at least. PocketPC and Windows Mobile seemed like a good platform at the time.

Power Hunger

PDA hardware sucks juice at an enourmous rate. I did try the 1,500mA battery extender for the Toshiba e755, but stuff as usual won’t perform if built with materials costing below a certain price point.

I tried to replicate that with software on a power hungry platform and failed miserably.

I will start making use of GPS now on a dedicated gadget, a dedicated tool instead of multiple options of none.

Explorist

The Magellan Explorist 210 is (Thales/Magellan cheapest model) currently selling for about $150 (S&H included) at RedOrbit. Simple, B&W, low-res but it has everything one needs for navigation. Period.

It has no expansion for SD Card but has 22Mbytes of internal memory, from which about 20% gets used by its firmware. It can hold 2,000 waypoints, 1,500 more than the cheapest Garmin (old entries get replaced by new ones if you ran out of space). It has a rugged body in live colors.

I already let it drop from the bike (yes, they do sell a bike holder for about $40 bucks) and just got a barely visible scratch. Thales got bought recently by Shah Capital Partners which hopefully knows what they got on their hands. It is good stuff.

With this I’m giving up color, resolution, screen size and a “common” user interface for 18 hours of use on 2 AA.

The Explorist is a well designed product (still missing dedicated Mac packages) that includes a Geocaching Manager and a software package to read/transfer data from its own MapSend topographical and street level maps.

You get a basic map data with the model itself. I can see highways, city names and where the water should be. For another 75$ or so you can get a CD with 3D Topo images of the whole US (or unlock the DVD with maps that ships with the product). You can zoom down to 100 feet on its US BaseMap.

I like the response time of the digital compass, because I never got anything even close with any combination of GPS card and software on the PDA. It obviously uses the GPS data to tell time and it has a very basic and easy to follow sequence of commands.

By plugging its USB cable to a PC running Windows you see its internal memory as a directory structure from where you can drag and drop text files ready for use by any ASCII editor.

GeoTagging

After riding for a while in Capitola for some pictures during its Art & Wine Festival I could grab the .loc file from the the current tracking session or Active Trace log. The plan was to geotag the pictures I was taking with the location data from my track.

Software can batch process a whole image directory looking for pictures taken within a given time interval. You need to convert the original .loc file to .gpx format/file with GpsBabel.

The minimalist Grazer then will edit the EXIF headers of the matching pictures with their corresponding latitude, longitude and altitude. You can see the results with the freeware Exifer (the author asks for a postcard for registration).

Now I can upload those images to Flickr or some other site with geotagging capabilities and a map interface.

[Update: According to this post, you can turn on "Read GPS data from Exif header" on Flickr by going to this link, after that new photos while uploaded should have their location info extracted and used. I can see the Exif data for a particular photo including GPS data. So far I haven't been able to use that data to place a photo on their map.]

[Update 2: A workaround involves providing GpsTagr with the corresponding .gpx file based on which your Flickr photos should be geotagged, that did the trick of setting up the location for each picture and displaying them on a map. Remember to sync the camera clock with your GPS time.]

The search is over. Let the real work begin.

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