Geotagging maps your photos

The shoebox of photos and folders of old negatives have been replaced by the virtual piles of pictures we take, fail to label, and leave unsorted on our computer. The problem has gotten so bad, the comic strip "Cathy" devoted a recent week to the topic.

Every digital picture we take has a dimension to it that should help in sorting: a embedded time stamp that notes when the picture was taken (as long as your camera's time is set correctly).

What if we could add another dimension — a set of coordinates that tells us where we took the picture? We can. Geotagging puts a pin on a map when we take pictures.

Think of geotagging as a new view into where you've been, one that doesn't rely on your memory.

Geotagging pairs location with time to help sort out where and when a picture was taken. Depending on hardware, the latitude and longitude — and sometimes speed, direction and altitude — are attached to the photo.

Although geotagging dates back several years, two recent entrants into the field make it a casual activity. I tested the Eye-Fi Explore, a new model of the original Eye-Fi storage and Wi-Fi photo transfer card; and the iPhone 2.0 software, on both an original iPhone and the iPhone 3G, which embeds location data.

Eye-Fi Explore

The Eye-Fi Explore ($130, www.eye.fi) is a 2 GB Secure Digital (SD) memory card with a built-in computer that manages an on-board Wi-Fi radio. The basic features work the same as the original Eye-Fi ($100) I reviewed last year (Personal Technology, Nov. 10).

The two extras in the Explore model are Wi-Fi-based location finding through a partnership with Skyhook Wireless, and photo uploading via Wayport, a national Wi-Fi hot spot operator that powers the networks in most McDonald's. (The first year's service is included with the card; it's $19 per year thereafter.)

The Eye-Fi card appears to a digital camera exactly like any other SD card. You simply take photos, and the Eye-Fi accepts the data from the camera as it should, but simultaneously takes another kind of snapshot: It records a list of the names and signal strengths of any Wi-Fi gateways in the vicinity. These Wi-Fi snapshots are used later.

Whenever the Eye-Fi Explore detects a network you've configured via included software, or finds one of Wayport's locations or an open network, the card tries to start uploading photos.

Eye-Fi uses Skyhook Wireless's technology to produce GPS-like results. Skyhook has trucks that drive around cities all over the world to record the public names and signal strengths of regular Wi-Fi base stations.

Skyhook is limited to towns and cities; it can't provide information in rural or wilderness areas, and it doesn't have worldwide coverage yet. But it's often better (and faster) than a GPS receiver in cities with tall buildings — so-called concrete canyons.

When an Eye-Fi Explore spots a network it knows, the card sends the Wi-Fi snapshots it has taken, receives Skyhook's educated guesses, and pairs that information with photos, geotagging them for upload.

In my testing around Seattle, the Eye-Fi generally performed well, pinpointing my position within a few hundred feet, or sometimes even just a few feet. During one bike ride, the Explore decided I was in Hamburg, Germany, rather than the Emerald City, but that was a rare glitch.

A bit harder was finding networks to upload photos. Wayport has 10,000 hot spots in the U.S., but 9,000 are McDonald's. The rest are hotels, and very few are in Washington state. (wayport.know-where.com/wayport/)

And, despite McDonald's ubiquity, the fast-food chain is not well-distributed throughout Seattle. I am not a fast-food snob, but it took two weeks of testing before I was within range and had the time to stop into a Wi-Fi-equipped Mickey D's to confirm uploading worked without extra effort; it does.

One side issue with turning on support for Wayport uploads is that you must also agree to allow photos to upload through "open" networks — those without a password or login screen, which typically are simple personal access points not secured with a password.

The legality of using someone's network without permission is dubious, depending on the state (and country) in which you live. This option shouldn't be tied with perfectly legal use of Wayport's network.

iPhone 2.0 Location Services

Apple added location awareness to the iPhone in a January 2008 release for the original "2.5G" model that uses relatively slow cellular networks. The iPhone determined location using a combination of triangulation of cellular towers and Skyhook's Wi-Fi calculations.

With the iPhone 2.0 software, the iPhone's built-in camera adds geotags if you choose. This software was released in early July for all original iPhones, and is the operating system on all iPhone 3Gs.

The iPhone 3G has a GPS receiver built in, alongside its support for faster data connections. The 3G uses assisted GPS, in which a cell tower and Wi-Fi positioning help the receiver lock onto satellite signals in seconds instead of minutes.

Location Services, as Apple calls it, can be turned on or off systemwide through the General section of Settings. With the option turned on, every program that could grab your location asks permission when it wants to use coordinates, whether to find you a nearby restaurant or geotag a photo.

I've tested both the original iPhone and iPhone 3G's geotagging ability. The original iPhone works about as well as the Eye-Fi in sticking a pin in a photo's location. The iPhone 3G with its real GPS hardware provides fairly precise mapping, especially outside.

While you can download photos from the iPhone via a USB dock or cable, and then upload them to an online service, software developers have released several upload packages via Apple's App Store, many of them free, including a SmugMug application and third-party programs for Flickr viewing and uploads.

This is a nifty option. You can take pictures and have them automatically upload and appear in your online galleries and on your map as you travel about.

Unfortunately, Apple's current software release (2.0.1 as of this week) doesn't allow these applications to upload full 1200 x 1600-pixel photos taken with Apple's Photos program.

Developers have thus chosen to let you take pictures within their programs for best results, as they can capture and transfer full-resolution images with all the correct tags. This is clearly a bug, not an intended limitation, and Apple needs to fix it.

The iPhones old and new still suffer from a low-resolution (2 megapixel) fixed-focus camera of mediocre quality. Add a bit of focus, better optics and a bigger image sensor — like the cameras in some Nokia phones — and a future iPhone could be a powerful geotagging tool.

Geotag, you're it!

Geotagging is definitely moving toward something that anyone with a camera could use.

What's still to come is sophisticated desktop application software that can integrate with maps and other information online, but give you a fast and multilayered view into your photographic past.

Just as better desktop and application search can do away with organizing files and e-mail into folders, so too could we shed our digital shoeboxes in favor of where and when with geotagging.

Glenn Fleishman writes the Practical Mac column in Personal Technology.