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Geotagging with external GPS receivers now possible (updated)

GPS receivers: Holux, QStarz, Transystem

A few weeks ago, we released app and firmware updates that enable a handful of external GPS receivers to be paired directly with the Unleashed, to provide GPS location data for geotagging without the need of a smartphone.

This is great news for those customers that were unhappy with their smartphone’s location precision, or simply prefer a more independent geotagging solution. This might be to extend battery life of the smartphone, or to enjoy longer battery life of external GPS receivers, especially on long trips off the grid.

The compatible GPS Receivers are:

  • Holux M-241 Plus
  • QStarz BL-1000ST
  • QStarz BL-1000GT
  • QStarz BL-818GT *new*
  • Transystem GL-770

After pairing one of these GPS receivers with your Unleashed through the app (Menu->Your Unleasheds->Edit Unleashed->Accessories), you will see new GPS Modes in the first picker of the GPS settings. In addition to “OFF” and “Smartphone”, you will now also have the options “External GPS only” as well as “External GPS with smartphone fallback” (We hope the new icons make it clear which is which). The first new option will exclusively use GPS data from the external GPS, and not of the smartphone, whereas the second option will use the external GPS while it’s available and providing valid data, but will automatically fall back to using the smartphone location otherwise.

We’ve also added a few new LED colors/sequences to make using the Unleashed without the app a little easier:

  • Lightblue: when an Accessory (such as a GPS receiver) is connected, but the app is not connected, the led will slowly pulse lightblue instead of turqoise.
  • Red blink: alternating with the normal sequences, the Unleashed will blink red to show that there is an error, until now mostly GPS related errors. You can then start the app to see details about the error, or simply check that the the external GPS receiver has a Fix and is connected. Some of these errors are:
    • External GPS receiver not connected (even if it then uses Smartphone fallback)
    • GPS data not valid (even if using last known position)
    • GPS accuracy too low

Comparing the receivers

The Holux has the Unique feature that it uses a single AA battery, for which you can buy replacements anywhere in the world. At the same time battery life is not as good as with the rechargeable Li-Ion batteries of the other options. The QStarz devices provide a little more data than the other two receivers [update: Transystem caught up], and we’ve implemented a neat little feature where you can use the POI button on the Receiver to trigger the camera. But they are also the most expensive. We recommend the BL-1000ST rather than the BL-1000GT, since the Unleashed will not make use of the 10Hz update rate, so it is not worth the extra cost. The BL-818GT doesn’t support the triggering functionality, as it lacks logging, and thus the button is not for POI saving. The Transystem device is more affordable than Qstarz, while providing just as precise position data, but has a quirk that it uses a non-standard USB-A to USB-A charging/data cable. So don’t lose that!

Right from the start, we had planned to make the Unleashed directly compatible with external GPS receivers, but technical challenges forced us to decide against pursuing backwards compatibility to GPS receivers using Bluetooth Classic. Unfortunately, at the time of Launch that basically left us with no options, since virtually all GPS receivers used Bluetooth Classic. However, in the past few years, the above devices were released, so we put a lot of effort into making the Unleashed compatible with external accessories in general, and added support for each of the GPS receivers one after the other.

While we had to reverse engineer Holux’s Bluetooth Protocol (and we got the Date portion wrong for a while), QStarz was kind enough to provide documentation that allowed us to implement support for their devices much more quickly. Transystem went one step further: They used a standard protocol defined by the Bluetooth SIG, and when we found a small issue with their implementation and had additional wishes, they swiftly made changes and added support for those in a firmware update. So a big thank you to both QStarz and Transystem for your support!

So, finally, the Unleashed now enables direct geotagging with external GPS receivers for Nikon as well as Canon DSLRs!