The app for iOS and Android that is available in their respective "App Store" is only for updating firmware on the TAP adapter. There is a separate app (only available for Android here:
http://techartpro.com/0831-LM-EA7-Config.apk) that allows you to change the list above (e.g. I have a 100mm lens so I might change ƒ/29 = 100mm instead of 90mm). None of the apps allow you to set the
active focal length being used with the adapter. The only way to change this is to follow the steps outlined in the instructions.
Example when changing to 35mm focal length:
- Set camera f-stop to f/22
- Press shutter button so that the shutter fires (takes a photo)
- Set camera aperture back to f/2.0
- Delete photo taken (optional)
After that, the recorded focal length will be 35mm in the exif data. This is also fed to the IBIS system in the camera. It's all a bit clumsy and I wish there was an app that allowed to change the active focal length from the phone. Unfortunately, this would increase battery drain (something the TAP already suffers from) as it would require the bluetooth module in the TAP to remain active listening for connections. I stopped worrying about what focal length the TAP writes to the exif data and just manually set focal length when I change lenses for IBIS only. It's easier and faster. I set C4 to bring up the IBIS focal length setting and it takes considerably less time to change focal length.