Adobe 12040118 - After Effects Standard, Руководство

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6. Adjust the Matching Softness controls to determine the width of the transition band between completely matched and completely unmatched
pixels or how smoothly the affected areas blend with the original image.
7. Select Invert Match if you want to invert the matte so that the white areas become black and the black areas become white. (The matching
color is black in the matte and is processed by the grain effect regardless of the Amount setting. The inversion doesn’t affect any other
settings.)
8. If you’re using both a color matte and a layer mask, choose one of the following from the Combine Match And Mask Using menu:
Screen Makes the matte white wherever either the mask or the color match is white.
Multiply Makes the matte white where both of the inputs are white.
9. Choose Final Output from the Viewing Mode control.
Generate a layer matte
In some cases, you may want to use a different layer or track as a mask for the layer that uses a grain effect. This type of mask allows unlimited
control over exactly which parts of an image are modified and by how much.
1. Apply a grain effect to the image.
2. In the Effect Controls panel, choose the layer that you want to use as a mask from the Mask Layer control in the Blend With Original and
Masking Layer controls groups.
3. Choose a masking mode from one of the standard track matte mode options.
4. If the masking layer is a different size than the current layer, choose one of the following from the If Mask Size Differs pop-up menu in the
Masking Layer controls:
Center Centers the masking layer over the current layer.
Stretch To Fit Resizes the masking layer to match the dimensions of the current layer.
5. If you’re using both a color matte and a layer mask, choose one of the following from the Combine Match And Mask Using menu:
Screen Makes the matte white wherever either the mask or the color match is white.
Multiply Makes the matte white where both of the inputs are white.
6. Choose Final Output from the Viewing Mode control.
Change the preview region
You can use the Preview Region controls group to change the position or the size of the preview region for a grain effect.
Because adding or removing grain can affect sharpness of detail, you may want to preview an area of fine detail, such as a human face or some
text. When you remove grain with the Remove Grain effect, a best practice is to preview an area where the grain is most clearly visible or most
objectionable, such as a large expanse of solid color.
You’ll achieve the best results by experimenting, applying small increments to each of several controls in the Effect Controls panel, and viewing
the results in the Composition panel after every adjustment.
1. After applying a grain effect, click the Center button in the Preview Region group of controls in the Effect Controls panel.
A cross hair is centered in the Composition panel.
2. In the image, click the desired center of the preview region.
The preview region redraws, centered in the new position.
3. To change the dimensions of the preview region, change the Width and Height values in the Effect Controls panel to the desired size, in
pixels. (Larger preview regions can result in slower rendering.)
4. Select Show Box if you want to outline the preview region in color. If you want to change the outline color, next to Box Color do one of the
following:
Click the color swatch and select a color in the Color Picker dialog box.
Click the eyedropper button, and click a color anywhere on the screen.
5. View the results:
To view the fine detail of the noise structure, zoom into the preview region.
To examine the noise in each channel independently, click the corresponding color channel icon in the Composition panel.
To increase the interaction speed and RAM preview duration, use the Region Of Interest feature in the Composition panel to reduce the
area that’s processed. (See Region of interest (ROI).)
To retain an image of the current frame in its current state, click Take Snapshot in the Composition panel. You can then click Show
Snapshot to view the most recent snapshot instead of the active composition, and to toggle between the current and previous states
of the preview region. This technique is extremely useful for evaluating subtle adjustments. (See Snapshots.)
To compare the preview region with and without the grain effect, click the Effect switch next to the name of the grain effect in the
Effect Controls panel to temporarily disable the effect. Click Take Snapshot in the Composition panel, click the Effect switch again to