The form of the face looks natural but tends to appear backlit when shooting against bright backgrounds such as the sky, and this causes the face to appear dark.
Raising the camera to a position where you look up also makes your expression appear bright and clear. A good tip is to raise your chin, not just your gaze, and face the camera.
When you don’t want to photograph your face, place THETA on top of your head. Your hand will appear a lot in the shot but you can shoot while hiding your face and body.