Searching for loose gear and dropped eyepieces after a Star Party ?

Any tips for efficiently scanning a field for dropped and lost
equipment after a Star Party has been held? I figure a good metal
detector and maybe a small rake could be useful for locating
everything from lost eyepieces, mount parts and even an odd lens or
two.

Probably can fetch some nice change for this stuff on the classifieds
for an easy afternoon's worth of work.