Seeing Qstarz

A while ago, I wrote an article entitled So, where was this taken?, in which I discussed the problems of remembering where you had taken particular photos and concluded that the answer was to use a geotagger (see the article for details). There are quite a few such devices on the market and I finally plumped for the Qstarz BT-Q1000X because of its long battery life (currently up to 42 hours) and because of the good reviews I had read.

Unfortunately, the unit I received didn’t work. I lost confidence in the make and model and returned it against a refund. That wasn’t the end of the story, however, because I was still having difficulty placing some of my photos and so I decided to give Qstarz one more chance. This time, I am happy to report that the unit functions perfectly. It is quick to lock on to the satellites (even indoors) and faithfully records my position at intervals (I have set this to every 10 seconds).

When I get home, I connect the device to the computer’s USB port (which also recharges the battery) and run the supplied software, having downloaded my photos from the camera to the PC.

The software then inserts the latitude and longitude of each photo into its EXIF data. This is a very accurate position (including up to 4 decimals of a second). This is my position when I took the photo, of course, not the position of the possibly distant object that I am photographing.

The software also produces a plot of my track on a section of Google map. I walked a track this morning so as to have something suitable to show you. Here is the track as produced by the software. (Click to see a larger version.)

My track on Google maps
My track on Google maps

While the track itself is accurately shown, the position of the photos (indicated by the camera icon) is less so. Several photos are shown to have been taken in the same place when in fact there was a distance of several meters between them. However, these positions are good enough just for locating the area where your photo was taken and if you feed the EXIF coordinates into Google maps, you get a more accurate position for each photo. (Remember that if your longitude is west of the meridian, you have to add a minus sign to the longitude!)

You can also project your track onto Google earth as shown here.

My track on Google Earth
My track on Google Earth

The same remarks about the positions of photos as made above apply here also.

On both maps, you can click on the camera icon to display the photo(s) taken at that point.

Part of a photo's EXIF data, showing inserted latitude and longitude
Part of a photo’s EXIF data, showing inserted latitude and longitude

There is another annoying inaccuracy. As long as I am moving, the unit tracks my position correctly enough but if I remain still in one place for a while, a phenomenon called “drift” appears. This causes spurious loops on the track as if I had been walking backwards and forwards time and again crossing my stationary point. These fictitious movements can be discounted, of course but it does spoil the look of the track should you wish to record this for later viewing.

The 10-second interval is perfectly adequate when you are exploring on foot. I don’t know how well this would work if you were taking photos from a train or other fast-moving vehicle. You can only change the interval via the supplied software so you cannot change it in the field.

I don’t usually want to know the location of my photos to within a few meters. Knowing the town or, at a pinch the street or square, is usually good enough. So far, the Qstarz looks perfectly capable of delivering this level of accuracy and more.

My difficulty usually comes from moving from Place A to Place B during an outing. I may then have a struggle to know which is the last photo at A and which the first photo at B. By typing the latitude and longitude of the photos into Google maps, I can completely resolve the uncertainty.

I can switch on the device, check that it has found the satellites (the orange light flashes on and off), drop it in my pocket and forget about it until I return home and geotag my photos.

If I discover anything further of importance, I will let you know.

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About SilverTiger

I live in Islington with my partner, "Tigger". I blog about our life and our travels, using my own photos for illustration.
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10 Responses to Seeing Qstarz

  1. Hm…this seems very cool. Just yesterday I took a photo of a church in a city I wasn’t that familiar with and had to do a weird google search to find where it was so I could see when and where the sunset would hit it. If I had something like this, I wouldn’t have had to do that. Thanks for sharing.

    • SilverTiger says:

      There are now several models on the market, all with different characteristics (e.g. replaceable batteries v rechargeable built-in batteries) so it’s worth looking to see which suits one’s pattern of activity best.

      I wanted something that would run for at least a day before recharging and would record a whole week’s travel. I think that only the Qstarz BT-Q1000X fits that description. I was disappointed when the first unit simply didn’t work but this one seems to be fine.

  2. Ancient Brit says:

    I still can’t locate the reference for using geotaggers to create artwork that’s only visible when the track is published, superimposed on a streetmap, but I did find a bunch of other references that might be of interest (not that I think you’d be interested, but readers might be):

    http://en.wikipedia.org/wiki/Geotagging
    http://en.wikipedia.org/wiki/Geocaching
    http://en.wikipedia.org/wiki/Geodashing

    and a website that’s the focus for one group of geotagger-based games:

    http://www.gpsgames.org

    You name it, someone will find a way to turn it into something you’d never imagine. Like the guys who ramp up the sound systems in their cars to such a level that not only can no-one fit in the car, but you can’t stand near it either because the volume is soooooooo loud:

    http://www.popsci.com/cars/article/2003-06/car-stereo-can-kill-you-cool

    Yep, some people have way too much money and time on their hands. 🙂

    • SilverTiger says:

      I suppose this is evidence of human inventiveness at work. The late great Richard Feynman used to compare science to play and I think play often leads to discovery.

      At first sight it seems mad to turn your car’s stereo system to a loudness that is (literally) damaging to the occupants’ hearing (“Disco on wheels,” says Tigger as yet another goes by or, more annoyingly, halts at the traffic lights near us) but I think perhaps it derives from human obsessiveness that always seeks to push things to the ultimate which always eludes us, of course.

  3. Reluctant Blogger says:

    Goodness me! I had no idea such things were possible. Not that I would use it as I take so few photos. I have recently been going back through my photos and labelling them to make them searchable and often I have had no idea where they were taken – even down to the country sometimes.

    I don’t need one of these devices, I just need to be more organised at downloading them and labelling them within a shorter time of taking them.

    Can you not snap the lines to the roads? I use mapometer for my runs and it has a snap to road option which makes it much easier to use.

    • SilverTiger says:

      When you move about as we do, it isn’t possible to work out your route on a map afterwards. On the ground you can do certain things such as photograph street names, borough notice boards and station names. Otherwise it becomes tricky especially when a short bus ride is indistinguishable from, say, a lunch break. I sometimes have to do a lot of detective work to locate photos and this all takes time.

      In any case, I don’t see the problem. The Qstarz maps where I go and – more important for my purposes – puts the latitude and longitude on each photo. Its location is then recorded for as long as the photo lasts.

      I don’t think it matters how many or how few photos one takes. Memory is fallible, and it’s often hard to remember when and when an old photo was taken.

      There’s very little difference between carrying a geotagger and, say, a mobile phone with GPS capability, except that the geotagger suits my purposes a lot better.

  4. Peter Harvey says:

    I have read your two pieces about geotagging with great interest. I didn’t even know that such things existed, but now I have decided to get one as I have the same problem as you when taking photos on the move.

    As I understand it, this is a device that sits in your pocket and keeps a record of where you have been, and this record can then be uploaded to a computer and plotted on a Google map. Additionally, it will add geographical co-ordinates to the EXIF data of the photos that you take.
    That is the point that I don’t understand. If the Qstarz is operating independently of the camera, how does it know afterwards where which photo was taken? I can see that it could be done with timing, but that would require very accurate synchronisation to be useful for photos taken from a train for example. How does it work?

    • SilverTiger says:

      Yes, it works by means of the software comparing the dated/timed entries in the log with the dates/times of photos in their EXIF data. My log is set to an interval of 10 seconds which is good enough for my purposes and economical enough to give me about 7 to 8 days of logging in one log. You have to make sure that your camera’s clock is set accurately, though it is possible to make allowances in the software, e.g. if you forget the clocks have gone back/forward.

      The geotagger’s log contains not only positions but also data such as velocity, which helps with the accuracy of the derived positions. The problem doesn’t arise in trains because the metal case surrounding you prevents to device finding the satellites anyway!

      It will presumably work on, say, an open-top bus or a boat, though, and I think it unlikely that the speed of these vehicles would introduce serious errors unless you are working to surveyors’ precision. (In that case, you would need something more accurate than a geotagger.)

      Most of the time, I get the actual street and a pretty good position in that street. That’s plenty good enough for my purposes as my usual problem is identifying the actual town!

      You can now buy cameras with geotagging built in (and some camera phones also have this) but as these only tag each photo, I prefer a standalone device, as you can use this to geotag many sets of data from different cameras.

  5. Peter Harvey says:

    Many thanks. One detail. You talk about setting the camera’s clock. Does the device pick up its own time from a satellite, or does that have to be set as well, synchronised with the camera?

    • SilverTiger says:

      Yes, it picks up the time from the satellites but, to be honest, I don’t know what happens when you change time zones. This is something I will have to check before I travel abroad.

      The battery on my current unit has turned out to be faulty and I have had to return it for replacement. Assuming the replacement is good, I will write a follow-up post on geotagging and will try to include in that a definitive reply about the clock-time.

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