- Joined
- 15 May 2004
- Messages
- 6,898
The water drops act as LENSES which could burn spots in your paint.
As I was a little boy I tried to get a thin paper catch fire by the sunlight with a convex lens which they normally use in philately (stamps). A water-drop is konvex unless you wipe it off. Exaggeration: The bundled light can burn a hole in the paint. That's what I was talking about.
Acid rain together with road- or industry-dirt will hurt the paint too.