Taking pictures using a Nokia N900

Photo with Geotags

Photo with Geotags

I’m still impressed by the features, the versatility and the usability of the N900. I’m also still impressed by the quality of the built-in camera. It does not beat my Canon A650, but it gets close enough to leave the Canon at home when riding the bike. Plus the 5MP images are more handy than the quite huge 12MP images of the Canon.

I still need to figure out how to cope with its focus and exposure settings, though. Most people might be pleased with the results of the auto mode, but I’m not. There are limits for automatisms, and in such cases you need to help the camera manually. Of course this requires more knowledge about photography at the user’s end.

Here are some wishes for the further development of the (excellent) camera application anyway. Try to find out the main difference of the following photo compared to the one on top of this posting:

Photo without Geotags

Photo without Geotags

Got it? Yep, the latter photo has not geocoding information embedded. How comes?

When you take a picture, the camera application grabs the current location information (latutude and longitude), connects to the internet and contacts a server to get a location name by doing reverse geocoding. After this process was successful, both the geocoordinates as well as the location’s name are added to the meta data section of the image file. That’s just great and makes it unnecessary to do the geocoding by correlating some tracklog to the photos after the trip. Thanks to anyone involved.

Recently I’ve been hiking along the german-french border. The phone indicated that it will connect to a french provider (actually »orange«) if necessary. To avoid roaming costs, I set the N900 to offline mode, which, according to the manual, disables cellular, WLAN and bluetooth connectivity. The GPS subsystem, however, still was working, which was a good thing to keep my navigation application up and running. In offline mode, the camera behaves as follows:

  • While taking a picture, it asks whether it should disable the offline mode to do the aforementioned reverse geocoding. There’s nothing wrong with that, except for the fact that it shows this as a modal dialog each time you take a photo. The dialog comes up right at the moment when you press the camera button half down to focus the object to capture. As the dialog is modal, you can’t take the picture before you have cancelled the dialog. That’s really a showstopper when you try to capture a moving target.
  • During my last test, the dialog was not shown while the button was pressed down halfway, but when the image was being processed. That’s better, as it does not prevent you from taking a picture. It still kept asking for each individual image, though.
  • If you cancel the dialog, the camera won’t connect to the web to do the reverse geocoding. However, it subsequently also denies to write the latitude and longitude to the image file, though a GPS fix is present.

This triggers the following requests:

  • Do not alert the user while he’s interacting with the camera application, e.g. alert about missing web connectivity while the image is being processed, not while the user is taking the picture.
  • Write latitude and longitude to the image’s metadata if a GPS fix is present, regardless whether the reverse geocoding was successful or not.
  • Alert the user only once a session, not for each individual picture.

The camera application remembers the last used mode persistently. The Canon, however, automatically falls back to auto mode each time you switch it on. IMO it would be great if the N900 behaved the same. In case you want to take a snapshot and you notice that you are still in video mode, which you used three days ago, it might be annoying :) .