Custom gradients are the key to many of the
coolest Photoshop tricks and effects. If you produce
photo-realistic work or simulated 3D, gradients are vital.
Capturing those subtle shadings that exist in reality
requires precise gradients.
The Gradient tool, which shares space in
Photoshop's Toolbox with the Paint Bucket, is actually a
collection of tools grouped together in one icon. After
selecting the Gradient tool, take a look at the Options Bar.
You'll see buttons that allow you to select from among the
five variations of the Gradient tool. (All five tools can
use any gradient color scheme.)
LINEAR GRADIENT TOOL
When you drag a gradient, the colors will be distributed
perpendicularly to the angle of drag.
Notice that the distribution of the gradient
within the selection starts at the point from which the
gradient is dragged and ends at the point where the mouse
button is released. In the top example, the gradient begins
and ends with transparency. The gradient itself is therefore
restricted to the area over which you have dragged. In the
middle and lower examples, the gradients begin and end with
colors. The area before the beginning of the drag is filled
with the first color; the area past the end of the drag is
filled with the last color.
RADIAL GRADIENT TOOL
The gradient will be drawn in a series of concentric circles
from the start of the drag outward to the point at which the
mouse button is released.
(Notice that one of the seven black-to-white
gradients was dragged at an angle conflicting with the other
six. This produces a visual anomaly, a conflict in the
"light source" that is creating the shading.)
ANGLE GRADIENT TOOL
The Angle Gradient tool wraps a gradient's color pattern
around the starting point of the drag. This is best
demonstrated using a circular selection
The insert in the lower right corner shows
the gradient used with the Linear Gradient tool. The
Transparent Rainbow gradient starts and ends with
transparency. In the circle, notice how the transparency
(seen as white) is both to the left and right of the
line-of-drag. The colors of the rainbow are wrapped
clockwise around the line-of-drag.
The Angle Gradient can be very effective for
shading, when used with an appropriate color scheme. In this
example, the gradient both begins and ends with black.
REFLECTED GRADIENT TOOL
The Reflected Gradient tool does exactly that: it reflects
gradients. The same gradient will be drawn in either
direction from the point from which you drag.
In the top example, the Transparent Rainbow
gradient was dragged from the center. Notice that the color
patterns to the left and right are mirror images. On both
sides of the center point, magenta is the first color. In
the lower example, a simple white-to-black gradient is used.
(A linear gradient sample of each appears in the boxes below
the examples.)
DIAMOND GRADIENT TOOL
The Diamond Gradient tool reproduces the gradient's color
scheme in four directions from the point from which you
drag. The line-of-drag establishes a corner, and the
gradient is duplicated at 90-degree angles around the center
point.
OTHER GRADIENT TOOL OPTIONS
In addition to selecting how the gradient will be created,
you are offered the choice of blending mode and opacity. All
of the standard modes are available, as well as the Behind
blending mode.
Other Options Bar choices for the Gradient
tools include Reverse, Dither, and Transparency.
REVERSE
When checked, this option simple flips the color scheme of
the gradient. (Sharp-eyed readers may have noticed that a
number of Photoshop's default gradients have been reversed
in the examples above.)
DITHER
Dithering allows Photoshop to subtly mix two colors where
they meet. This helps prevent "banding," which can be
defined as visible stripes of color. An exaggerated example
shows the impact.
TRANSPARENCY
Several default gradients have built-in transparency,
including the Transparent Rainbow used above. When this box
is not checked, the transparent areas will be filled with
the neighboring color(s).
The Transparency box was checked for the
first and third samples, unchecked for the second and
fourth. As you can see, without transparency, Photoshop
filled the extreme left and right of the Transparent Rainbow
with the first and last colors. In the lower pair, the
transparent areas are evenly filled with the two neighboring
colors.
In the next installment of this series,
we'll look at editing the color schemes of existing
gradients.