Power Windows

A Power Window is the second method of Secondary Grading. While a Qualifier isolates an area based on its color data, a Power Window isolates an area based on its physical location on the screen. It is essentially a mask.

Types of Power Windows

Open the Window panel (the icon looks like a square with a circle inside). Oraphim provides several default shapes:

• Linear: A rectangle.
• Circle: An ellipse.
• Polygon: A custom shape where you draw the points.
• Curve: A freehand bezier curve for complex rotoscoping.
• Gradient: A linear fade from 100% to 0%.

Common Window Workflows

1. Relighting a Face

If an actor's face is slightly underexposed compared to the bright background:

1. Create a new Serial Node.
2. Add a Circle Window.
3. Position the circle over the actor's face in the Viewer.
4. Adjust the Softness parameter so the edge of the circle fades seamlessly into the background.
5. Go to the Color Wheels and raise the Gamma. You have successfully "relit" the actor artificially.

2. The Vignette

A classic cinematic technique is to darken the edges of the frame to draw the audience's eye to the center.

1. Create a new Serial Node.
2. Add a Circle Window.
3. Make it very large, covering the center of the screen, with a massive amount of Softness.
4. On the Window panel, click the Invert icon (it looks like a small black-and-white circle). Now, the node is affecting everything outside the circle.
5. Lower the Gamma and Lift to darken the corners of the room.

Combining Windows and Qualifiers

Power Windows and Qualifiers are not mutually exclusive; they are designed to be used together on the same node to create perfectly clean isolations.

Imagine you used a Qualifier to isolate a blue car to change its color. However, there is a blue street sign in the background that is the exact same hue. No amount of tweaking the HSL parameters will separate them, because the color data is identical.

1. On the same node where you built your Qualifier key, go to the Window panel.
2. Draw a Curve Window roughly around the physical location of the car.
3. Because both tools are active on the same node, Oraphim uses a boolean AND operation: the color change will only apply to pixels that are both blue AND inside the physical window you drew. The street sign is safely excluded.