In Nemesis, the Enterprise was able to detect B4's parts from quite a distance and get a general location for each of them. Yet a tricorder could not detect any of the parts until the tricorder was nearly on top of a part!
Maybe, I missed or forgot something like some kind of energy dampening field that was effecting the tricorder. But if there was a dampening field should it have also effected the ship's sensors?
accuracy of ship sensors and tricorders
Moderator: Vympel