Levels and Curves in Photoshop

Levels and Curves in Photoshop can be used to make dramatic color corrections. See the Tutorial below

This photo has too much of blue. Green should be visible where the buffloes are. Photoshop can correct this.

Go to Image>Adjustments>Levels

The Levels dialogue box opens.

Choose the eyedropper tool on the extreme left. Then click on a light spot in the image as I have done.

Some of the green now shows up.

Now go to Image>Adjustments>Curves

Choose the Green Channel from the dropdown box. RGB is the default.

Now push the diagonal line where I have marked with an arrow. This will lighten the image.

Now see how the image has changed. The bluish tinge has gone. The waters look the colors it should and the grass looks green.

Go to Image>Adjustments/Brightness/Contrast to bring up this dialogue box. I have adjusted both the brightness and the contrast.

This is how the finished image looks.
Also see here.