on one of my cars i have these water spots or light acid rain marks on my hood that can only be seen under certain lighting conditions like flourescent, parking garage lights ect
Depends on whether they're still just "marks" or if they've progressed to actually etch into and eat away the clear coat. If they've gone that far then you might be out of luck since you now have to actually remove clear coat to level them. I bought a car that has an extreme problem like that on the hood. If it bugs me enough I"ll go find out how much clear coat I have and then decide if I can get them removed - which would probably take wet sanding to start the process. For my purposes it might be faster and safer to just pay the $500 to have the hood repainted!