There's no evidence that reflective tape scares birds away. Only social media posts and rumor say it does. Bottles of water don't scare flies or dogs with full bladders, either.
There is an occasional problem with a bird actually striking...
Focusing was not an issue ... a 5 second exposure was.
But there's really no need to select a focus spot, unless you have a subject very close to the drone and a larger distant background (something which is rarely done in drone photography)...
Thanks .. that's not why the pic wasn't brighter, but it explains why the camera used such a long exposure time to get proper light levels.
.. that and the aperture being stopped down to f11.
But if you try the settings they should give very good...