Paintball markers are likely a better choice, but very high cameras will still be out of reach. And then there is the issue of finding the cameras, but something like http://www.jet-protect.com/CS300Klanding.html can help...
It was discussed on Bruce Schneier's blog, on which the topic of camera detection comes back regularly.
https://web.archive.org/web/20100611052640/http://nexgadget.... https://www.schneier.com/blog/archives/2010/04/detecting_bei...