I'm doing sound on a film that will feature mountain climbers. The director want's to capture ambient sounds as we shoot safely from the bottom of the mountain. He's expecting the climbers to be about one thousand feet above us. So my question is, can anyone recommend a wireless lavalier system with a reliable operating range at that distance? We will be in the middle of nowhere, so interference from other signals shouldn't be much of an issue. I use Sennheiser G3 systems now and I'm quite certain they will not cut it.
Cheers,
Jeff