@intro
Geotagging Essentials
Add GPS data to your photos -- automatically
In digital photography, how a picture looks is critical: a surprised expression on your wife’s face when you present her with an anniversary ring, or the kids jumping over a sprinkler...in their school clothes. As cameraphone pixel resolution increases to 5MP and beyond, the quality of the image is also important, as well as storage options, portability, and usability. For some photographers, however, the critical factor is where you took the picture, not how it looks. A police investigator wants to take snapshots of a crime scene and keep a record of the exact location, or a house hunter wants to take a series of pictures and know the address of each new home.
Geotagging (a.k.a., geocoding) is a process of adding GPS data to photos so you know where you took the shot. There are several key advantages to this. For starters, it means you can map out every photo and see where you took it, typically using Yahoo! Maps or Google Maps. This is helpful for archiving photos – you can go back and look at any shot and find out exactly where you were when you pressed the shutter button. It also shows you a record of your life: you were in London for a rock festival last year, and in Lisbon for vacation with the extended family in March. Combined with other photographic data, such as the date and camera you used, you can easily search for and find stored photos and enjoy a photo collection more.
Geotagging actually goes far beyond that basic description, though – it involves Web sites such as Flickr, programs like Picasa 2 and Panaramio, digital camera add-ons, GPS adapters, and cameraphones with built-in GPS features. There’s an automated nature to geotagging where you hardly have to think about the GPS coordinates. It’s a new concept that brings several disparate technologies together – digital photography, mapping, GPS data, and even RSS (real simple syndication). At the end of the day, however, it’s all about knowing where a photo was taken, which is especially useful three years from now when you can’t remember that one wooden bridge by the summer cabin, or where your firstborn took his first step.
In some ways, there’s a level of complexity to geotagging that can make your head spin. Adding the GPS data is easy; using it on your computer can be an interesting challenge. In this overview of how geotagging works, we’ll cover the basic concepts first, and then the gear and programs you can use to stamp your location on photos.
Geotagging
Basics
The best way to understand how geotagging works is to
explain the manual process. Using a device such as the Garmin eTrex and a
digital camera, you would first take the picture you want. Then, you would take
a second picture of the GPS device showing the latitude and longitude. As long
as you have enough storage available, you’ll have a
record of each photo’s location. Now imagine that the camera itself stamps the
photo with the coordinates so you can skip the second location photo – that’s
geotagging. Of course, no current camera on the market has built-in GPS. (Stay
tuned – this is a feature that many camera makers are developing.)
Instead, you’ll need a hardware add-on or a cameraphone that does support GPS. That way, as you take photos, the location data is added to each photo. When you load the images onto your PC, you can then see the GPS data in the properties of the file, or use a program that reads the data automatically and shows you the location on a map. Of course, using sites such as Flickr or Panoramio, or even desktop programs such as Windows Photo Gallery in Vista or iPhoto on a Mac, you can add basic location data yourself. So, say you went on a vacation to Italy: you could manually add that tag to every photo, and even group them according to a manual geotag. You can’t map these photos, because sites such as Google Maps need exact coordinates, but at least it gives you a rough idea of the location. Yahoo! also offers the Zurfer (zurfer.research.yahoo.com) “proof of concept” utility for smartphones that lets you add location data to your shots. Another handy use for geotagging: once you have stamped photos with coordinates, the data stays there in the EXIF portion of the image file, which means you can use it in programs such as Adobe Photoshop CS3. The EXIF data is a permanent record that stays with the image forever.
Hardware Options
Since no digital camera supports geotagging yet, there
are several products that either add GPS functionality to an existing camera,
and one particular cameraphone that has geotagging built-in – albeit with an
add-on software program.
Nikon
D2Xs Digital SLR and MC-35 Cable
Nikon offers a way to geotag photos using their high-end (and expensive) D2Xs
digital SLR (single lens reflex) camera with the MC-35 cable. Here’s how it
works. You first connect the cable to the camera using a proprietary interface.
Then, you can connect the cable to any GPS that has a serial interface, such as
the Garmin eTrex. (Note that there are two versions of the eTrex – one with a
serial interface and one with a USB port. If you own the USB version, you can
get a serial-to-USB adapter.) When you snap a picture, the camera reads GPS
coordinates form the cable and handheld GPS. It’s actually a lot of extra
gadgets to carry around, but it works well, and the D-SLR camera captures
beautiful images that no cameraphone could match.
Sony
GPS-CS1
If you already own a Sony digital camera such as the CyberShot
DSC-S500, you can add geotagging data to photos with the Sony GPS-CS1. It’s a
bit funky how this product works, however. As you take photos, you carry the
GPS around with you. Then, when you load the photos onto your computer, you
connect the GPS using a USB cable. The GPS reads data and time stamps on images
and syncs them to where you were at the time of the photo, and embeds the GPS
data into the image. You have to use the Picture Motion Browser software
included with the camera, and only works with Google Maps through a proprietary
link – so Flickr users are out of luck.
Nokia
N95 and ShoZu
The Nokia N95 is one of the powerful smartphones on
the market. A slide-out keyboard and a second slide-out music controller make
it compact and user-friendly. The three killer features, though, are the
built-in GPS, Wi-Fi, and a 5 megapixel camera that lets you adjust tonal
quality and zoom. Used together, the provide the best
the best solution on the market for geotagging. It won’t work out of the box,
however – you will need the free ShoZu cell phone utility (www.shozu.com). ShoZu is the “middleman”
program that lets you add GPS data to the photos and transmit them
automatically to Flickr.com or some other photo management site.
Once installed, you do have to fire up the GPS mapping program to let the N95 find satellites. Configuration takes place partly on the Web at Shozu.com and partly on the phone. There’s also a somewhat obscure setting in ShoZu for enabling GPS (its under Setting) and in Flickr, for reading EXIF data from imported images. It’s entirely seemless once you configure it: you snap a photo, ShoZu uploads the photo to Flickr, and then you can view the image son a map just by clicking a link.
Software Options
Geotagging is partly a process of adding GPS data to photos, and partly using
those photos with a software program, a photo management site, or an online
mapping tool. Once you see the exact spot you took a photo on a map, you’ll
want to geotag just about every photo you take (and convince others to do the
same!)
Flickr.com
Flickr is by far the best site to use for geotagging because it directly
supports the feature, both through an API that connects to your phone over the
Internet, or by reading files that have been geotagged. It’s quite impressive:
using ShoZu (www.shozu.com), you can
transmit geotagged photos to Flickr automatically. Snap the shot, then visit
your Flickr page and you can then see the photos and click a link to see them
on a Yahoo! map (Flickr is owned by Yahoo!). Or, when you import photos that
have the EXIF data for GPS coordinates, Flickr automatically reads the
longitude and latitude and shows you the name of the city where you snapped the
photo.
Google
Maps
Google Maps (www.maps.google.com) also
supports geotagged images – through an RSS feed from a photo management site,
and directly from Picasa 2. It’s a bit confusing to use RSS at first, because
you need the complete RSS path, and then you have to add the string “&georss=true”
to the end, and paste it into the search field. So, for example, if you use
Flickr.com, you would use the following syntax:
Google Maps is a powerful tool because you can zoom in incredibly tight to see the location of your photo – e.g., was it near the swimming beach or the city park? A hybrid view shows you satellite images and street indications in one view. Combined with the new Street Maps feature – which is only available in a few American cities but expanding eventually – you can match up your photo with the 260-degree panoramic shots built-in to Google Maps, which is fun and useful at the same time.
Picasa
and Panoramio
In Picasa 2 (www.picasa.google.com), it’s much easier to see maps – you can load your geotagged photos into the manager, and then select a menu option to see the image in Google Maps. Google also offers a tool specifically designed for geotaggers: Panoramio (www.panoramio.com), which lets you map photos either by typing in the location manually or by having the site read the EXIF-embedded GPS data. The only problem with these two programs is that they do not have the strong following of a site such as Flickr.com, which lets you see your geotagged images and compare them to other those of other users near the same location – and even chat through an internal messaging system about photography, the weather on a certain day, or any other topic. (Flickr has become as much a social networking site as a photo manager.)
Conclusion
Geotagging is a hot topic – adding location data to photos is sure to catch on
with digital camera users and photo enthusiasts, as well as those who enjoy
tracking GOS data with a handheld gadget. Camera makers will have to follow
suit with GPS add-ons and built-in GPS capability – so that someday, all of our
photos are GPS enabled.