3 Tips For Using Water To Enhance Your Images Page 2
Tip #3: Rainbows
You'll find rainbows when you are between the sun and water droplets of the right size. We most often notice them during clearing storms when facing away from the early-morning or late-afternoon sun, but they can also appear in waterfalls and sprinkler spray--anytime the sun angle and water drop size are right. Keep your camera ready when storms clear, and keep an eye out for rainbows anytime there's water in the air.
Water can give you some great photos. But it can also damage your camera, lenses and other photo gear. Take care not to get your gear wet, unless you're using gear that was designed specifically for that purpose. If you want to experiment with rainy-day or ocean-spray photos, buy a waterproof single-use camera, and use that--it should withstand just about any wet situation, and if it doesn't, you're out less than $20.
To get long exposure times in brighter light, stop the lens down, and use a slow film or a low ISO setting on a digital camera. You can also use a neutral-density filter to reduce the amount of light reaching the film or image sensor, but ND filters are quite expensive.