How to get the best tonal contrast
The best tonal contrast contains complementary colors (opposite colors) and high saturation. Two colors on the opposite sides of the color wheel creates contrasting colors. The saturation of the colors affect how prominent it is over tonal contrast.
Contrasting hues
In the image below, the color contrast is good because the colors are almost opposite of each other. The image is loud and grabs attention.

The image below has low color contrast but it still looks great because it has good tonal contrast. Also, low color contrast is not always bad. Low color contrast makes the photo quieter and well for the scenery photo below.

You can make your photos more striking by increasing the color contrast. Below is an example that compares the color contrast. With less color contrast, the image will look dull and quiet. High color contrast makes photos look striking.

Saturation
The color saturation affects the intensity of the effect. The more vibrant the colors, the more color contrast. A color photograph can be separated into tonal information and color information. When you combine those two, you will end up with a regular color photo.

How prominent the color contrast is depends on how high the color saturation is. With less saturation, the tonal contrast becomes more noticeable. With more saturation, the color contrast takes over.


Simplicity
Color contrast also works better with fewer and larger color masses. In the image below, the checkboard pattern has weaker contrast because similar colors are separated and there is an even number of colors (50% orange, 50% cyan). The image on the right has stronger contrast because there are only two areas and more of one color than the other (75% orange, 25% cyan).

When you introduce other colors into the photo, the color contrast will decrease. Even though yellow and purple are main colors in the left image below, the introduction of other colors (beige, red, and blue), makes the photo less dynamic. The image on the right is an example of good color contrast. There are few colors and more difference in mass between the two complementary colors.
