a nice article about reflection and car paint.
www.fxguide.com/article482.html

this is a really good tip for beauty reflection
''Then there was a second stage consisting of beauty lighting. "This is the stage that makes it look not only real but beautiful and here the team used techniques learned from their experience with car commercials," says Morton. So the team used long digital lighting boxes, "which is what makes a car look so great, producing these long gradated reflections".''