In the previous installment of this series
we began a look at the specific layer blending modes and how
they affect various color combinations. Let's finish up the
list.
As in Part 2 of this series, we'll use a
test pattern. Remember that the bottom color is the base
color, the overlying color is the blend color, and the
product of their interaction is the result color. Here are
the base colors:
The Spectrum gradient runs across the top of
the image, with a black-to-white gradient immediately below.
Solid bars of black, 50% gray, and white are next, followed
by red, green, blue, cyan, magenta, and yellow fading to
white. These gradient and color bars will be used as the
base colors to show how each blending mode affects the
interaction with a range of colors and tints.
The blending colors, on a separate layer,
are the Spectrum gradient and a black-to-white gradient.
When the layer blending mode is set to
Normal (assuming 100% opacity), the blend colors block the
base colors.
In Part 2 of the series, we explored the
following layer blending modes: Dissolve, Multiply, Screen,
Overlay, Soft Light, Hard Light, Color Dodge, Color Burn.
We'll now look at the remaining layer blending modes.
The Darken blending mode evaluates the top
and bottom colors. If the top color (the blend color) is
lighter than the bottom color (the base color), then the
result color is darkened. If the blend color is already
darker, it is unchanged. In the following figure, notice the
overlap of the two grayscale gradients. You can see the
points where the gray values are near-equivalent,
represented by the diagonal white line.
The Lighten blending mode is the compliment
of the Darken mode. If the lower color is darker, it is
lightened. If not, it is left alone. In this figure, look at
the overlapping grayscale gradients and note the dark
diagonal line.
Difference compares the brightness values of
the blend and base colors and subtracts the lesser values
from the greater. Blending with black produces no change
(the brightness is zero and subtracting zero from any number
leaves the original number.) Blending with white produces
inverted colors. The results can be stunning. Take a look at
the diagonal black line in the upper-left of the following
image. That represents the place where the two overlapping
gradients had identical values. Also on the left, in the
middle of the image, look what happens when the Spectrum
gradient crosses the neutral gray bar. Interestingly, only
gray and CMY result.
Exclusion can produce results similar to
those of Difference, but often less dramatic. In the
following image, you'll see that blending with neutral gray
had a radically different result (only gray remains, not
CMY). Also compare the lower-right quarter of the Exclusion
and Difference samples. Blending the lighter side (right) of
the grayscale gradient with the horizontal RGB and CMY
gradient bars results in beautiful inversions of the base
colors.
Hue works with the saturation and brightness
of the base color and the hue of the blend color. In the
image below, the saturation values of the black, gray, and
white bars and the grayscale gradient prevent the blend
color's hue from having any effect. In contrast, the
grayscale gradient on the upper layer (to the right) has a
tremendous effect on the underlying gradients.
Saturation uses the hue and brightness of
the base color and the saturation of the blend color. The
saturation of the upper grayscale gradient (vertical, on the
right) eliminates any color. However, notice the impact of
the vertical spectrum gradient (left) on the underlying
grayscale gradient.
Color maintains the brightness value of the
base color and uses the hue and saturation of the blend
color. Black and white as base colors are, of course,
unchanged.
When using the Luminosity blending mode,
Photoshop works with the hue and saturation of the base
color and the brightness of the blend color. Note that
blending color over grayscale values has an impact (left),
while blending grays over grayscale (right) leaves the
blending colors unchanged.
In the next installment of this series,
we'll look at blending modes that are not found in the
Layers palette.