Walker Effects Manual

Glow

The Glow effect is an advanced plug-in for generating beautiful blooms and glowing regions. It provides a wide array of options such as built-in masking, levels, size, colorizing and other expert features.

Glow works by extracting a region of the source layer, blooming it, and then re-compositing it over the original. Selection of glow regions can be achieved using a channel matte or a color key. Additionally you can use masks to control where the blur is applied.

View Mode

To help work with the various components of Glow, the View Mode offers isolation of specific features and helps you see what is happening at each stage. Each View Mode will enable only relevant effect controls, while others will become disabled temporarily. Only in the Composite View Mode will all controls be active.

Glow Source

This View Mode displays the selected Layer unmodified. If the layer is set to None, then the layer on which the effect is applied will be used.

Glow Selection

Use this View Mode to see the areas that will be glowed. The glow selection is controlled by the Match Color settings or the Matte Channel settings, depending on which mode is chosen.

Glow Mask

Use this View Mode to see the Mask by itself. If the Mask is not enabled or invalid then a red X will be rendered instead.

Glow Only

This View Mode displays the fully processed glow layer by itself. This is useful to see exactly what the glow is doing and can even be used as an output option to use with other effects.

Composite

The Composite View Mode outputs the final result of Glow. In this mode, all effect controls will be enabled and the glow will be applied to the source layer.

Glow Layer

The Glow Layer specifies the input layer and options for building the glow.

Layer

This specifies which layer to base the glow on. Typically, this is set to None and the layer which the effect is applied is used. However any layer in the composition can be used to build the glow.

Selection Method

Rather than glowing the entire image, Glow uses a selection to build the glow. There are two methods for selecting the image region:

Match Color Key

This method uses color keying to define the image region to glow. When using this mode the Match Color, Tolerance, and Feather controls will become enabled.

Use Channel Matte

The other method of selecting the glow region is to use a channel as a matte. A channel can be used with levels to pull a precise region from an image. For example, you could use the luminance channel to generally apply glow to the lighter areas of the image.

Match Color

When the Selection Method is set to Match Color Key, this color specifies the color to key from the Layer. Any color matching this will be included in the glow.

Matching Tolerance

You can increase the range of the selection with the Match Tolerance. Starting from the Match Color the Tolerance expands the search region to include more pixels.

Matching Feather

The Match Feather can also be used to increase the selection region. However the feather fades in pixels based on their closeness in matching creating a softer matte.

Channel

When the Selection Method is set to Use Matte Channel, this menu will be enabled. The selected channel is used to determine what areas of the image will be glowed. You can use Levels to fine tune the selection region.

Invert

If this checkbox is enabled, the glow region will be inverted. This works for either Selection Method.

Premultiply With Alpha

When Premultiply With Alpha is on, the selection region will be multiplied with the Layer's alpha channel. This works for either Selection Method and may be useful when the Glow Layer has transparency.

Levels

The glow selection can be further adjusted using the Levels controls. These controls work similarly to the standard Levels effect.

Input Black

As the Input Black is increased, the channel becomes darker. Visually it appears as though the darker areas grow, eventually overtaking all pixels. The Input Black and Input White values can be moved closer together to create contrast.

Input White

Opposite of Input Black, Input White increases the range of white pixels. As the value is decreased, the brightness of the image increases until the whole image becomes white. When the Input White value is less than the Input Black, the channel will be inverted.

Gamma

The grayscale levels between white and black can be biased towards either end of the spectrum using Gamma. At the default value of 1.0, the interpolation from black to white is even. Gamma values less than 1.0 bias the gray levels towards black, creating a darker image. When the Gamma value is greater than 1.0 the gray values are pushed towards white brightening the image.

Output Black

The Output Black value clamps the channel value at the specified level. For example, if the value is set to 45, then no pixel in the resulting channel will be darker than 45 (measured in bits per pixel).

Output White

The Output White level limits the maximum brightness of the channel. For example, if Output White is set to 128, then no pixel in the resulting channel will be greater than 128.

Render Order, Levels First

This checkbox allows you to control whether levels are applied to the glow before or after its blur is computed. Applying levels before blurring produces quite different results than blurring first. With the checkbox off, the levels will tend to affect the glow falloff directly whereas with the checkbox on, levels will affect the spread and reach of the glow but the falloff will remain normal.

Mask

Layer masks can be used to control what areas of the image glow is applied. The Mask group is only active when a valid Path is chosen. Paths must be closed. Whether the Mask is active or not is indicated by the word 'On' or 'Off' next to the Mask group name. When Use All Paths is enabled, the name of the Mask group will change to reflect the current usage of paths (ie 'Mask On: Using[1,2,3]).

Important: Masks used by this plug-in should be turned off in the Timeline Window by setting their mode to None. Otherwise, the mask will be applied to the layer by After Effects as well. Furthermore, none of the mask controls in the Timeline Window are used. All settings regarding masks are controlled within the effect.

Path

To specify a mask, select the desired path from this menu. You may also choose to Use All Paths, in which case this control will become disabled. Only closed paths are valid.

Use All Paths

With this option, it is not necessary to explicitly select a path. Instead, all available closed paths are used. The paths used are indicated by number in the name of the Mask group control.

Uniform Feather

Enabling this checkbox means that mask feathering will be equal in the horizontal and vertical directions. Only one Feather slider will be provided. When this checkbox is unchecked, there will be two sliders for feather: Feather X and Feather Y. Note that the feather controls in the Timeline Window are ignored by the effect, and when using multiple paths they are all given the same feather amount.

Feather

This slider controls the size of the feathering in pixels. The feather is actually rendered by After Effects using the built-in masking tools, and will perfectly match results you get with standard masking. You can turn off Uniform Feather in order to control the feathering amount independently on the X and Y axis. In this case, to sliders will appear: Feather X and Feather Y.

Invert

When invert is on, the Mask will be rendered inverted. So rather than color being filled inside the path shape, it will fill all areas outside the closed path.

Mask Mode

To control how the Mask interacts with the Matte you can specify the Mask Mode. The default Mask Mode is Multiply, which produces the most commonly expected result. However, you can use any other mode to subtract, add, or otherwise affect the Matte with the Mask. When the Matte is Off, the Mask Mode will be disabled.

Opacity

The Opacity controls how much the Mask affects the Matte. With a value of 0, the Mask is not rendered, and at a value of 100 the Mask is fully applied. Note that Mask Opacity behaves differently than the mask opacity in the Timeline Window.

Colorize

When creating a glow, you can use the original input colors of the Glow Layer or you can use the following controls to tint and colorize the effect.

Enable

To enable Colorize, this checkbox must be on.

Color Presets

A collection of built-in presets make easy work out of colorizing and provide great starting points.

Number of Colors

Colorize supports either 3 or 5 colors. When set to 3 colors the Mid-Shadow and Mid-Highlight controls become disabled.

Color Controls

Each color targets its respective range of the image. The Shadow color, for example is mapped to the darkest areas of the image, while the Highlights are mapped to the brightest. Keep in mind that with Glow, the darker areas are transparent and will have less effect.

Colorize Opacity

The amount of color applied is controlled by the Colorize Opacity. At a value of 0, no color is applied to the glow, while at 100 the color is fully applied.

Cycle Mode

The Cycle Mode determines how values are handled beyond the normal value range when the Cycle is used.

Cycle

The Cycle offsets the input phase of the Channel. This essentially cycles the grayscale gradient, wrapping it around. This can be useful for shifting colors through the image, or to alter the mapping created by a channel such as Hue. The Cycle Mode can be used to determine how the values are wrapped.

Size

The Size controls how much the glow is bloomed. Size is used in conjunction with Intensity to control the visible amount of glow.

Note: In earlier versions of Walker Effects, this group of controls was called 'Blur'.

Quality

This menu allows you to decide what type of blur is used for comuting the size. You can choose from Fast Blur or Gaussian. When set to Automatic, the effect will render the Gaussian Blur for best quality and Fast Blur for draft quality.

Uniform Blur

This checkbox controls whether the glow is applied equally in the horizontal and vertical directions. If it is turned off, separate sliders for Size X and Size Y will become available.

Preserve Transparency

When this option is enabled the alpha channel of the original layer is preserved. Otherwise the glow region has it's own alpha and may extend beyond the edges of the original alpha.

Composite Mode

This is the final composite mode used to apply the glow over the original layer. The default mode Screen & Dodge is a proprietary composite mode to Walker Effects ideally suited for compositing special effects. A long list of other modes are also available for creating practically any type of glow you need.

Opacity

The final glow opacity is controlled by this slider. If set to 0, Glow will have no effect on the original layer.

Blend With Original

Use this slider to blend the result of the effect with the original input layer. If Blend With Original is set to 100, the effect will not render.