Hi all,
I've been experimenting with light painting for a while now, and I seem to struggle to get a smooth, even exposure on metallic cars.
Does anyone have a tutorial on how best to achieve this? I'm able to get something just passable on low res (Instagram and facebook) but at full res I'm just not happy. Help!! 
For example, in the image below I'm struggling to get the shadows on the doors to be smooth and gradational (although its hard to see in this pic due to low res):
