Rhyzome is correct ... as a photographer, I'm well-aware that tourists to the Grand Canyon are encouraged to buy their photographs from the Gift Shop, because it is virtually impossible to take good photographs of the Canyon, the years of smog from L.A. has permanently 'hazed-over' the Canyon ... and, it has been this way for quite a few years ... I don't advise against rainwater for it's pollutants, I don't recommend it, just because you have to add calcium and magnesium, plus the hassle of gathering it, so why not just make it easier, by using other water sources ?? ... :smokin: