One of the features introduced in our latest release (FoCal 2.10 Beta 1) is automatic lens database updates, and today we’ve released the first update to improve accuracy and fix unresolved lenses.
A bit of background…
Figuring out which lens is attached to a camera is a bit more complicated than you might expect!
The Nikon F-mount was introduced 60 years ago – back in 1959 – and extended over time to meet new requirements introduced by the addition of autofocus, metering and aperture control. The Canon EF mount came later in 1987 and was fully electronic. But up until the introduction of digital cameras in the late 1990s, there was no real need for the camera to know exactly which lens was attached, just some characteristics that were necessary to control and take the shots. Digital cameras brought a file system and with that image metadata containing information about the shot. Today we expect the lens name and details to be associated with each image we shoot.
The camera manufacturers used very basic codes to identifying lenses, and offered little help to third-party lens manufacturers (e.g. Sigma, Tamron etc) who ended up reusing some of these codes in such a way that it’s impossible to differentiate between certain lenses.
FoCal’s Lens Database
During the development of FoCal 2.9, we totally reworked the way we used information to determine which lens was attached to the camera. Using a combination of camera reported information, lens characteristics and some heuristic analysis we have hugely improved the accuracy and uniqueness of each recognised lens.
We added the feature to allow you to report a misidentified lens and we’ve had hundreds of reports raised (thank you!) which has helped us improve the database. The database was built-in to FoCal 2.9 (and 2.9 MR1) so it would only be updated with a new release of FoCal software, but with the release of FoCal 2.10 (Beta 1) we’ve made it so that the lens data is updated automatically.
How to Update the Lens Database
To update the lens database, just start up FoCal and it’ll do the rest automatically behind the scenes. At the moment, the new database is loaded on startup so you’ll need to restart FoCal to get it to use the new data.
You can see the version of the database under Settings > Version Information. FoCal 2.10 Beta 1 was released with database version 33:
Today’s update is to version 48:
If you’ve reported a misidentified lens, have another go and you should hopefully find it resolved correctly with this update!
As mentioned above, there are a few lenses that can’t be uniquely identified. On Canon, the one that crops up most is the early Sigma and Tamron 24-70mm f/2.8 lenses. There are a few more on Nikon (especially around distinguishing between teleconverted lenses) but we have made a recent code update which should help to resolve these in the future as we get more information.
We will be adding the option to choose the correct lens from a short list when we can’t determine which lens is attached – this will be coming in a future software release.
We’re not expecting any issues with this update, but would love to hear feedback to check it’s working as expected. Feel free to leave a comment below or use the Send Feedback button in the Settings tab of the software.