The law of condensation
by Anatolii Mikhailovich
Basic idea behind this or similar method is a simple law of physics: condensation will happen if humid air ( even at a low percentage of humidity) is cooled down.
All you need is a colder surface when temperature of the air is going up, OR temperature of a surface going down when the air is trapped.
* Take a bottle made of thick glass outside (close lid), so that bright sunshine can reach it (or just leave it outside at dawn - least effective, or dig it out from a colder ground - most effective). Sun will make air in the bottle hotter faster than it warms up the glass itself - you'll get a few drops of water.
By the way, Israel uses pipes made of some slow heat conducting material and placed vertically near trees to help them get water condensation and grow in the climate when rain is really rare.
* A large ground hole, covered in plastic sheet with a stone on it placed just above the water bucket - as described in other people's posts. If you've got time to make it, you'll get more water than just from a bottle.
* Digg out a few stones - underground is usually cooler than air just above the ground. Place those colder stones in a plastic bottle with hotter air. It works, but gives only a few drops of condensation on the stones, and stones are dirty :(