Think that those are not answers for his question. If you are above city, in atmosfer level, than you go for travel-descend, you can see buildings in that city. That is not sensor sharing, cause you will not see anything else that might be in that city. As for items you see that are out of your vision/sensor range, do not know why is it so, some gamplay reason probably. Anyway, yes, items that are on the ground you will always see, regardless of your vision range.