Have you ever tried to make a fire using a magnifier with pine needles as tinder? One of the tricks to successful fires using the solar method is to use tinder that is fibrous, dry and compact, yet loose enough for air flow. Pine needles alone are not dense enough to transfer heat, but if you grab a bunch together, about an inch in diameter, then bind it tight with a green strand of tall grass, and trim the end flush, it works. This allows a surface upon which to focus the light from the lens or reflector. You begin by focusing the light on the sheared surface, and when smoke begins to appear, very slowly begin to spiral outward, increasing the size of the spot to continue the combustion process. When it begins to produced substantial smoke, blow at the center of the smoldering pit to increase it’s size. Usually, a generated a coal is transferred to more tinder, but you will find that just continuing to blow on the bound pine needles will ignite the entire bundle itself.