Yes, common sense tells us that lenses will condense the sun-rays, and that can burn out film (or damage the sensor of your camera, or even your eye). I am aware of this. But we wouldn't have these nice photos if we didn't some times take the risk.

Fantastic photography Jaro! I need to learn how did you make it!

Thanks! Composing a shot is not difficult, but some times we will have to work for getting it right. I took a couple of photos just trying to get this angle right, but it paid off. :)