Getting a great photograph can often be about catching the right light.
For the picture below I was in Padley Gorge. The weather hadn't been great with a persistent cover of cloud, so I had changed tack from landscape photography to looking for macro subjects. However the sun broke through creating a beautiful dapple light on the brook. A quick change of lens and this was the result. The sun spotlights the bottom of a cascade showing the water coloured by the peat. The colour is fantastically transparent as the peat particles form a colloid in the water allowing light through. It's an effect just like your cup of tea before you add milk.