Complex sentence: While at the island LeRoy goofing around unwittingly takes photographs of the base and of Chaz (thereby identifying him) with an infra-red camera and leaves the tear-off part of the negative on the C-47's floor.
Split into simpler sentences: While at the island LeRoy, goofing around, unwittingly takes photographs of the base and of Chaz (thereby identifying him) with an infra-red camera. He leaves the tear-off part of the negative on the C-47's floor.