I think the main reason that they look so dim in the picture is because of the angel of the it. The center car is looking directly at the angel eyes, while the Z4 and 7-series are facing forward, and not the camera. Its well known that the headlights need to be viewed directly and not from an angle.
It would be best to re-take the pictures with the 3 cars facing the camera in an orientation like this.
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_^ - camera
the 3 lines are the angles the cars are on all facing the camera directly
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