
This is taken of a ditch near where I live. I saw this junk, just dumped there and thought about the symbiosis between the human and the nature...

First, I rotated the picture a few degrees and cropped it. Then I wanted to ephasize the illness of the whole by turning the picture into B&W, except for the rusty barrels and the brown water. I even enhanced the saturation of the barrels to make them stand out more. Mixing B&W with colour is a really easy thing to do and it works powerfully.
How it was done?

I used two layers, the original as the backround layer and a copied layer of the same image. The copied image on the top was turned into B&W just by desaturating it. Then, where the barrels are, I erased the top image with the eraser tool revealing the extra saturated colour image below, thus leaving everything else B&W except for the erased parts.