In this example, you'll be creating a simple animation that would change the amount of gray in an image over the span of 96 frames. You'll be manually setting keyframes using the tool UI.

To animate the amount of gray in an image using the Gray tool UI:

1. Click on the Gray tool and select the Amount attribute label, marking it for keyframing. A yellow rectangle appears on the tool node indicating that it has been marked for keyframing.
   
2. At the first frame leave the value at 1.00000.
3. Select the Set Keyframe button in the Tool Options (see Node-Specific Tabs) or the Player controls.

   A green line appears at the top of the attribute label, indicating that the attribute is now animated and has a keyframe at the current frame.

   
4. Move the time cursor in the Player navigation bar to frame 30.

   The green line changes to red to indicate the attribute is animated but has no keyframe at the current frame.

   
5. Change the value in the Amount field to .50000.
6. Select the Set Keyframe button.

   The green line changes back to red. Again, this indicates that a new keyframe has been added to the timeline.

7. Repeat steps 3 to 6 as required.
8. Select the Gray attribute in the Composition browser.
9. Select Frame or Frame All to view the curves in a Animation Editor (or press Home).