Add Grain effect
The
Add Grain effect generates new noise from nothing and does not take samples
from existing noise. Instead, parameters and presets for different
types of film can be used to synthesize many different types of
noise or grain. You can modify virtually every characteristic of
this noise, control its color, apply it to the image in several
ways, even animate it or apply it selectively to only a part of
your image.
This effect works with 8-bpc and 16-bpc color.

Original (left), and with effect applied (right)
The
distribution of the added noise over the color channels does affect
the overall color of the resulting image. With a dark background,
the noise tends to add to the image visually, so a red tint or more
noise in the red channel gives a reddish hue to the image. With
a bright background, the noise tends to subtract from the image
visually, so a red tint or more noise in the red channel gives a
cyan color. The result also depends on the Blending Mode control
in the Application controls group.
Note: The actual grain of your image may vary from the film presets,
because of factors such as exposure and scanning resolution.
You can use the controls for the Add Grain effect to do the following:
To reproduce the grain of a particular film or photographic
stock, choose the film type from the Preset menu for the Add Grain
effect in the Effect Controls panel.
To adjust the intensity and size of the applied grain and
introduce a blur, adjust the Tweaking controls group for the Add
Grain effect in the Effect Controls panel.
To modify the color of the added noise, adjust the Color
controls.
To define how the color value of the generated noise combines
with the color value of the underlying destination layer at each
pixel, choose a Blending Mode in the Application controls group.
To define how much grain is added to each tonal area in your
image and the midpoint, adjust the Shadows, Midtones, Highlights,
and Midpoint values in the Application controls group.
To animate the added grain, adjust the properties in the
Animation controls group.
To apply the effect to the entire image, choose Final Output
from the Viewing Mode menu.
Tweaking controls for Grain effects
The Match Grain and Add Grain effects
share a group of Tweaking controls. You can use these controls to
modify the intensity and size of the noise and to introduce a blur,
all of which can be done across the three channels or individually
for each channel. You can also change the aspect ratio of the applied
grain.
Note: The values of the Tweaking controls are relative
to the noise sampled in the source layer: a value of 1.0 leaves
that property of the source noise unchanged, while higher and lower
values alter the applied noise.
Adjust any of the following
controls in the Tweaking controls group:
- Intensity
- Controls the amount of variation in brightness and color
strength between pixels in the generated noise, which determines
the visibility of the noise. Increasing the value does not change
the position or size of each grain but makes the grain appear to
pop more; lower values give a more subtle muted appearance.
- Channel Intensities
- Controls the contrast between pixels in the generated noise
separately for each channel. For example, you may want to add more
grain to the blue channel to emulate film.
- Size
- Adjusts the size of the generated grain in pixels.
- Channel Size
- Adjusts the size of the generated grain in pixels independently
for each channel.
- Softness
- Sets the amount of softness in the grain.
- Aspect Ratio
- Controls the ratio of the width of the generated grain over
a constant height of 1; this setting is useful for emulating the
effect of anamorphic lenses or for aesthetic effects. A value higher
than 1 stretches the grain horizontally; values smaller than 1 squash
it horizontally.