The Ft2 cooker and the mini Ft2 testing a new type of solar distiller.
You need a dark glass inner jar as the container for your materials. It fits inside a larger clear glass jar which not only helps contain and concentrate the heat, but also acts as the collector. Of course you need a top cover otherwise all your good stuff would be lost into the atmosphere. I like to use glass or ceramic as shown by the white bowl setting on the larger collector.
As the concentrated sunlight from the reflectors heats the dark jar vapors will form and start collecting as little droplets on the inside of the clear drawer and top cover. When the unit gets hot enough these drops will fall to the bottom of the larger jar. I like to keep the white bowl cover empty until I see moisture gathering. Then I put some water into the bowl and it provides cooling which helps the drops form more quickly. Note that this thing will even continue to work for a while after the sun goes down and this is probably because of the residual heat .
When it cools you remove the inner container jar and then pour out the contents of the larger jar which have collected throughout the day into your Stash.
If you want to just eliminate moisture, then put a top cover on with a hole in it and this will concentrate your solution and allow the vapors to escape into the atmosphere. This works great for desiccating and drying any herbs or plant material that you want to dry.
The three mirrored reflector (Ft2 cooker) is inexpensive, easy to build, and very portable. I prefer glass because of its great reflectivity and the fact that it lasts a very long time unless you accidentally crack or break one of the mirrors. It is always a good idea to put some kind of backing onto the mirror. You can use plywood, or plasticized cardboard, and a little bit of glue. Even if you cracked the mirrors it is still quite usable even though it may not be as aesthetic as you like. Many of my reflectors have cracked mirrors but I am not ashamed of that nor do I think I will have seven years of bad luck. Oh wait, with all the cracked mirrors I may have several lifetimes of bad luck. But anyway it is wonderful to be using free sun energy and playing with something that you don’t have to constantly tend to.