I’ve built an AR app in unity, that is using some targets stuck on posts in outdoor exhibits, so there is a certain distance separating the user from the trigger, and that can’t be changed.
In any normal lighting conditions, the triggers work just fine. However if there is a bright sun illuminating the background behind the target (the target is shaded under a tree), it messes up with the pattern recognition, and the target won’t trigger the AR

If I lower my hand in view of the camera, even 1/10 of the frame height to cover a bit of the super bright background, the app will automatically recognize the target.
So I think it does have to do with the automated metering of the camera and how that affects the image recognition.
The question is, what can I do to remedy this? Is there a way to mask the camera image input so that it’s only revealing the center area to Vuforia? I’ve no idea how to help the situation.