How to ensure consistent visibility of the actor in a moving car shot in a wide open space?

[Ruth Vilas]

I was watching a scene with a car shot where the actor is sometimes barely visible and sometimes not. While this could have been intentional, I’m curious about what steps could have been taken to ensure the actor is properly lit and visible throughout the whole shot. I understand that having the car pass by darker elements outside (like trees) can block skylight reflections, but what if the scene takes place in a wide-open space with no trees or buildings? What techniques or considerations could have been used to achieve consistent visibility of the actor?

Polarizing and pushing light in at eye level would be enough? 

* I read about dps using a net stretched over the top like a shelf to control reflections and lighting on the windshield, not a lateral window. 

Edited March 10 by Ruth Vilas

[Stewart McLain]

Roll down the window?

[Stephen Baldassarre]

A circular polarizer on the lens will help but you'd also need a fairly strong light mounted directly above the camera and probably replace the window with one that has an anti-reflective coating.