Geotagging is the process of adding geographical location information to the metadata of photographs. It’s something I had been interested in trying for a few years. With GPS location information attached to a photograph, anyone can see exactly where it was taken using their choice of online mapping solution.
The cameras I was using didn’t include GPS facilities, Canon EOS 20D, 40D and 7D. This meant that I would need some hardware to actually capture the GPS data and then some software to apply the GPS data to the photos I took. As it was just something I was “interested in” rather than being something I had an actual requirement for, I didn’t want to spend a lot of money to accomplish this.
I looked at various dedicated GPS logging devices and it has to be said that these days they are tiny and not horrifically priced. However I didn’t want to spend £80 on a logger only to find that I had compatibility problems with my Mac or with the software I wanted to use. Also I didn’t want to add a potentially messy and time consuming extra step to my photo processing. So every time I looked into geotagging I ended up letting the idea slip.
Just recently I finally entered the 21st Century with acquisition of an HTC WIldfire smart phone running the Android operating system (version 2.1 for now with the promise of version 2.2 on the way). This phone has GPS hardware included so within the first few days of having the phone I started to investigate GPS logging applications for Android phones.
I soon discovered GPSTracker Lite, a freeware / donationware application by Gábor Telek. At the time of writing this article GPSTracker Lite is at version 0.7.1 and claims to work on all versions of the Android OS. I can only vouch for it working very nicely on my 2.1 powered Wildfire, so please take this into account if you want to try this for yourself.
When I go out to shoot and want to geotag the photos, I check that the clocks on my phone and my camera are in sync and then start up GPSTracker Lite on my phone before I start shooting.
The application faithfully records where I’ve been and will show me a map and various statistics about my journey relating to speed, altitude and distance travelled. It records all this information into a log file on the memory card of my phone. Data can be recorded in metric or imperial units and you can generate either a plain text file or a GPX format file. I use the GPX format as most geotagging software seems to readily import that.
When I stop shooting I stop GPSTracker Lite recording the data and connect my phone to my computer in order to read the generated GPS track file. I suppose I could just as easily email myself the log file direct from the phone, but I prefer to hook my phone up to the computer with a USB cable and read the file directly.
So, now I have all the GPS data from my photo trip and I have to attach that data to my photographs. How does GPSTracker Lite know when you’ve taken a photo? The very simple answer is that it doesn’t. This is why it’s important to make sure that the phone and the camera are reporting the same time. This system of geotagging works by taking the time stamp on each photo and working out from the GPS log where you were at the time the photo was taken. The better the sync is on the clocks the more accurate the tagging will be. As long as you’re not sprinting around the place taking your photos (if you are then you’re very fit and your camera kit is just nowhere near heavy enough) a few seconds difference won’t really matter, and it’s something that most geotagging programs can take account of anyway.
You also need to ask yourself just how accurate you want the geotagging to be. In my case it’s just for fun, I don’t really mind if the tagging is a few meters out. If your clocks are ten seconds out of sync then you might tag a photo with the position you were in ten seconds before you actually took the photo. Not a big deal for me. If it’s vitally important to you that your photos are tagged incredibly accurately then you are probably looking at a different league of geo-location precision anyway. Make your way to your nearest military hardware dealer and be prepared to pay a hefty price tag in order to get your geotag. The GPS harware built into a phone can be accurate to within about 10 meters, sometimes it will be spot on, other times it might show you standing in the middle of the river when you are stood shooting on the bank. This added to any fuzziness in clock sync will mean that this method will only ever be approximate.
Approximate is good enough for my purposes, so I’ll continue with the tagging process.
I use Adobe Lightroom for most of my photo processing and as the photo database for every shot I take. Once I get home with my photos I fire up Lightroom (currently at version 3) and import my photos as normal. I also plug my phone in so that I can read the GPS track log that GPSTracker Lite has created for me.
Once the photos are in Lightroom I use Jeffrey Friedl’s Geoencoding Plugin for Lightroom. I select all of the photos I want to geotag and then select FILE – PLUGIN EXTRAS – GEOENCODE. Jeffrey’s plugin presents a dialog where I can select the GPS tracking file I want to use and then just click the “geoencode images” button. There are various other settings in the plugin that can be played with, but for me it’s as simple as that.
Returning to my Library view in Lightroom I can now select any of the geotagged photos and using FILE – PLUGIN EXTRAS – VIEW LOCATION AT GOOGLE MAPS I can bring up an instance of Google Maps (or one of several other online mapping services, whichever you prefer) and see the location where I took the photo.
Many of my photographs end up on the Flickr photo sharing service, so the final step for me, after doing any processing I want, is to export the photos to Flickr.
One important note here, something that caused me a few minutes of confusion when I first tried this. Although the GPS metadata is now embedded in the metadata within Lightroom, you have to make sure that it is also included with the exported version of the photo.
To do this just select your chosen export method and make sure you add the “Shadow GPS Injector” to the export and tick the “enable” box.
I will be giving donations to both Gábor Telek for his GPSTracker Lite Android application and Jeffrey Friedl for his GPS Tagging Lightroom Plugin. Excellent tools which enable a photographer to geotag their photos at a reasonable price.