Contrast in Photoshop
Contrast is where an element of a picture stands out more than the rest, because of the colour. There are contrasting colours like blue and orange, or red and green. Contrast usually compliments the subject, but sometimes your subject doesn't contrast with the background already. This is where photo-shop can help. By creating a black and white photo-filter, you will cause your whole picture to become black and white. Then using the brush, on black, you can put colour back into your picture. Change the colour to white to make the picture black and white again. But to do this you must have the photo-filter layer selected.