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SCL Photo Podcast 22: Geotagging!

SCL PodcastGeotagging, or embedding the location of where you took a photograph in the exif data, and why you should think about doing it!

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Show notes:

Featured Posts:

New Fujifilm S5700 S700 Guide.

Photowalk 50 - The Church and The UFO.


My Notes:

Today I want to talk about Geotagging, the technique where you embed or add the exact geographical position where you took a photograph. I'm talking about the latitude and longitude and sometimes altitude and direction, into your photographs.

I've planned on revisiting Geotagging in an episode for awhile, but I wanted to talk about it this week in response to the latest episode of Photonetcast, where the team have an interview with Mike and Charlie from ATP, who make Geotagging products. It was a great show, but the pro and semi-pros on the show were a bit skeptical about the benefits and uses of Geotagging, so I wanted to share some of my ideas on the benefits of Geotagging now, and maybe how it it could be used in the future.

OK, lets start off with the technicalities of Geotagging, how it works. The first step is always to make sure the time in your camera is correct. Then you simply walk around, carrying a small GPS receiver. The GPS receiver just listens for the Navigation Satellites, gets a lock on at least three, then performs simple triangulation to work out the lat and long. It then just stores this on it's internal memory (or a memory card), along with the time. It keeps on doing this as you walk around. Some models of GPS trackers also record altitude and direction. When you get home you simply load your photo's onto your computer, the GPS log from the receiver, and a piece of software looks at the time you took the photographs, checks the GPS log for the corresponding lat / long, then adds that to the photo's exif data, which is part of the .jpg file format. Some units can do this in the unit, without a pc, some require special software, but all rely on that basic principle of recording lat / long position and time, then syncing that to the time you took your photographs.

The process is simple for .jpgs - a bit more complicated for RAW. This is because camera manufacturers RAW files, the uncompressed data from the sensor is in proprietary format - that is it's different from camera maker to camera maker, and even from model to model, so it's very difficult to have devices and software to embed the data, but there are plenty of software applications out there that can do it, it's just that all the GPS Photo Taggers I've used don't come bundled with that software, but they should do soon.

Right, so that's the nuts and bolts out of the way, what's the point in Geotagging?

First up, when you tag your pics and upload them to Flickr or Picasa, you can look at them on a map, and let others look at them. Interesting enough by itself - you can share great photographic spots with others, get an idea of the environment with Satellite Views. I think its great to look at all the images you've taken at a particular area on the same map. See what your habits are. Do you always visit the same places, with the same views, are their areas around where you shoot that you haven't visited? Introduce other peoples photos on the same map, and you get other peoples perspectives and favourite spots, encouraging you to try different things.

One thing I do is produce Google Earth .kmz files - these are track files with embedded photographs, so you can view not only the pictures I've captured, but the exact path I took on that photowalk in 3d on Google Earth. It's pretty simple at the moment,and the areas I visit pretty boring - but imagine 3d tours, with embedded photos, of say your holiday trip to the Grand Canyon. We'll soon see automatic 3d slide-shows, with maybe embedded video and audio too - what a fantastic way to archive and share not only the photographs of a trip, but the experience of traveling around too. Instead of sitting through a boring slide show, you'd have 3d landscapes, where you photo's are rendered onto the scene, then you'd move on to the next image...

You can already submit Geo-tagged images to Panoramio, the people who look after the embedded photographs in Google Earth. You can have all of your own Geotagged images in your local copy of Google Earth on your PC, but if your photograph gets accepted into Panaramio it goes into the version of Google Earth that everyone gets - how cool is that! Imagine in a few years when they'll be millions of photos on Google Earth - then we'll have the ability to render those photos onto, or into 3d structures, like Google Street View - but on a Global Scale. Then think about what a resource it will be in the future - where you could look at various "skins" of Google Earth Photographs based on time - see how New York looked in 2008 compared to 2015 - brilliant.

Sometimes with new techniques, like Geotagging, to understand the potential benefits its easier to look back at old Photographs and wonder what it would be liked if they were Geotagged, and what we could learn from them.

Imagine if we knew the exact location, to the nearest yard or meter, where American Civil War, First or Second World War Photos were taken. How much of a resource would that be to historians? You could visit the exact spot where Capa photographed the Soldier being shot during the Spanish
Civil War, or where he went ashore during the Normandy Landings? I know that in some historical photographs there can be a building or land-mark to get a geographical fix from - but think about landmark events where there were lots of people taking photographs, say the Kennedy Assassination. You could easily recreate exactly where each photo was taken, and at exactly what time. What a boon for crime investigators.

On a Historical theme I was watching a Time Team Archaeological program last week where there first task was to find an old buried WWI bunker. They had photographs of it, but didn't know exactly where, so had to use aerial photography and ground radar to work out where to start digging. With a Geotagged photo they could have found it instantly.

There's lots of practical and commercial uses for Geotagging. If you're a surveyor, architect or engineer, just take a photograph of where you are and it's location is forever stored, with the image, especially in environments where the Geology changes fast, like the Arctic or desert conditions.

The military undoubtedly use GPS in many situations. Laying a land-mine? Photograph and tag it for later removal. Troops moving across a battlefield could take pictures of unexploded armaments to pass to clearance experts. Obviously reconnaissance teams would use Geotagged Photographs for intelligence purposes.

Ah, I know you're thinking, so other professions might find great uses for Geotagging, or people in the future, but I'm shooting commercial work - so what's the point?

Well, some programs now, and many in the future will be able to store and sort images by location information. Often we can recall what an image looks like, and that gives us a clue to where it was taken, but without any idea of the date or folder it might be in. Say you're trying to find a shot of the car set-up you did maybe last year, on that track at Laguna, but you haven't got a clue where it is on your hard-drive. Just ask your PC to show you all the photo's taken with a mile radius of Laguna Speedway racetrack. Voila, there it is!

I guess what I'm trying to get across is that even if you're not interested in Geotagging to share your images on a map, or for the historical record, you should do it because we just don't know what wonderful ways will appear in the next few years to take advantage of that location information in Photographs - and you're better off embedding that info now, even if you don't know what use you (or others) might make of it in the future - maybe even decades into the future.

Oh, one more thing - it's no good having all this digital location info in your pics if you print them out - so why not think about writing the lat / long and date on the back of prints you do - for the next generations to use.

In a later episode I'll talk more about specific hardware and software you can use for Geotagging - in the mean time if you're interested in learning more, go to robnunnphoto and check out the Geotagging link under the main picture at the top of the page.

New End of Year Photo Assignment - "Shape Interrupted!"

We haven't had a photo assignment on the group flickr photo pool at, but I thought it was time for a new one. If you live in the Northern hemisphere the weather probably isn't all that good to be going out shooting - but maybe this will give you some ideas for new photographs.

The theme will be "shape interrupted", so shoot any two photographs on that subject, and upload it in medium size on the thread I've created on the robnunnphoto Flickr group.

Just for fun, no prizes I'm afraid, and we'll run it until the end of the year.

Technique challenges (No Time Limit):

No Sky Landscapes

Fill The Frame!

Dawn / Dusk shots

A Landscape Style Shot With Strong Foreground Interest

Remember to email me your photos if you'd like to me work on them for the Photo Workbench.

To contact me, just click on the link near the top of the page under the big picture.

Thanks for listening, see you on Flickr!

Join the Flickr Group!

Cheers, Rob.

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