The Trace Tool
The Trace Tool is the main tool used to create a mask.
The Trace tool has the following options:
- Feather: Lets you blur the edge of a mask, like a soft brush edge setting for the [Mask Brush] tool . The Feathering range is 0 to 10, with 10 being the softest. By default, feathering is set to 0, which turns this feature off.
You can use feathering to mask a blurred object behind the one that's in focus, or to mask the edge of a translucent item, such as a curtain.
You can also use the [Feather] tool to blur the edges of a mask after you've created it.
- Opacity: Lets you mask areas translucently. The Opacity range is 0 to 100%, with 100% (the default) being completely opaque.
You can use opacity to mask an object that is seen through a transparent or translucent area, such as a wall seen through transparent drapes or a couch behind a glass table. You use opacity when you define the mask for a highlight matte object .
- Straight Edges: Ensures that all new vertices are sharp and all new edges are straight, unless you choose a different vertex type from the right-click menu. Existing vertexes and edges are not changed.
When you don't check Straight Edges and you add a vertex in the middle of a line, you can click and drag that vertex (which is a sharp vertex). If you create a new vertex and drag, that vertex automatically becomes a smooth vertex.
- ** Hide Outline on Drag:** Turns off the display of the mask outline each time you drag the mask shape to adjust it.
Use the Edge tab to define the edges of an object :
- Sensitivity: Adjusts the edge definition. Lowering the sensitivity causes only the highest-contrast areas to be defined as edges. Raising it causes more edges to appear, but they may interfere with the true edges of objects.
- Display: Adjusts the appearance of edges from opaque to transparent.
- Recalc: Displays the Extract Edges from Image dialog box, where you can set options for defining default edges .
The right-click menu contains commands that let you choose different vertex types:
** Smooth Vertex:** A vertex with Bezier handles. The control points at the end of the Bezier handles are always equidistant from the vertex and 180 degrees from each other.
** Straight Vertex:** A vertex with Bezier handles. The control points at the end of each Bezier handle are always 180 degrees from each other and may have differing distances from the vertex.
Corner Vertex: A vertex with Bezier handles. The control points at the end of each Bezier handle are freeform.
Sharp Vertex: A vertex with no Bezier handles. This is the traditional vertex used in previous versions of Image Authoring. If a sharp vertex is surrounded by Bezier curves, there are no straight lines on either side of that vertex.