Emphasis Through Contrast in Color

As noted in Mary Stewart's Launching the Imagination, contrasting color can create emphasis, with the dominant color becoming the standard, and other colors becoming the exception (86). I learned this while working on a timelapse photomontage project. I use aerial photos of a particular area over 18 years of urban development. The oldest photo provides a kind of background because it is in black and white, with patches of more recent photos being in color (this was not an aesthetic choice--this was how the aerial photos were taken). In the original photos, however, there was insufficient contrast. The color photos had a sufficient amount of gray that it was difficult to distinguish between black and white vs color, therefore making it difficult to distinguish older from more recent. I ended up darkening the black and white portions and lightening the color portions. to make greater contrast between the two.