Well using a laser to evaluate the validity of the overhead vapor trails (laced with chemicals or not) has been effectively remedied an impractical choice due to the ineptitude of some ignorant individuals (you are now classified a terrorist to point a laser in the sky.. give me a break! .. The power level of pointers are in the class IIIc range, they are as about effective a blinding weapon as saline solution when pointed at an aircraft .. not much to report about) You are left with more expensive means to evaluate the problematic situation besides the fallout from the vapor.. to (...)