Compare the Grain

There are several ways to set up the viewports or images to compare the grain of two images:

• Use the Compare tool. You can also compare different grain settings on the same image to see which you prefer.
• Show the composite. If the two images are both in the composite, you can compare the grain if, for example, there is a matte on the front image or layers are arranged a certain way.
• Use multiple viewports. You can show the images in separate viewports, but make sure that the zoom for both is the same.

Once you can see both images (or clips), you can compare the grain, and decide on the size or color adjustments to apply.

While comparing the re-grained image to another operator using the Compare tool, you can use the Match Grain picker on the compare region. (You should not do this if you are comparing it to stored settings for the same image.)

Note: Grain is applied to the entire image (that is, the image that is visible with respect to the alpha channel) even when you are using the Compare tool. In other words, processing takes the same amount of time regardless of how much of the target image you are viewing.

Sometimes, you may need to reapply the original grain to a de-grained clip (for example, if you de-grained it get a better key). You can do this by comparing and matching the original clip to the de-grained clip across every necessary area of the image.

Note: You can also use this method to build a very accurate Add Grain setup from a grainy clip: de-grain it, match the grain, and save the setup to be used on other clips.

Using the Compare Tool

Compare your re-grained clip with one of five stored settings or an operator. This is very useful as a means of comparing the original (if saved in a store) and modified images.

The Compare tool includes an AB button, the Compare list, and three compare tool options in the Toolbar.

To use the Compare tool:

1. Click the Compare (AB) button.

The Compare tool options appear in the Toolbar.



2. In the Add Grain Controls, do one of the following to pick a comparison source from the Compare list:
• To compare to a stored setting, select the Storage number relative to your stored settings.

Note: To compare a store, you need to have previously stored settings.

• To compare to another operator, select Operator from the Compare list, and select the operator in the Operator Picker dialog.

Note: To select a Footage operator that is not in the current workspace, select Open Footage and use the browser to navigate to the desired footage. The Footage operator is added to the Footage Library.

3. In the Toolbar, do one of the following to draw a comparison region:
• Select Rectangle to draw a rectangular area in the viewport.
• Select Split Vertically to use a vertical region and then click or drag in the viewport to create a vertical limit at that point.
• Select Split Horizontally to use a horizontal region and then click or drag in the viewport to create a horizontal limit at that point.

Note: Alt-click or drag (Windows) or Option-click or drag (Macintosh) to toggle between a horizontal and a vertical split.

4. Enable Invert Region to toggle the comparison region between the inside and outside of the drawn area.
5. Enable Show Region Limits to show an outline around the comparison region. This option is only available when Rectangle is selected from the Compare Region list.

Note: To reset the Compare tool, select None from the Compare list in the Color Correction Controls.

6. You can continue the process by adjusting the luma of the grain.