This is a 43" diameter DIY grid free water parabola lens that can reach in excess of 1,000f The energy can be used to solar cook food. The water lens is running at about 80% of maximum power.
The water needs to be distilled, rain or R/O for maximum power. I used well water to demonstrate that it will work with groundwater. The popcorn was filmed with a Casio EXILIM Pro EX-F1. Main video Canon canon XH A1 Last siphon scene Canon 7d