Adding visibility masks to images If a paint object has a visibility mask, you can erase to a clear back- ground. Also, Canvas can protect transparent areas when you paint or edit in the image. You can add a visibility mask to a paint object that was created with an opaque background in Canvas or imported from another applica- tion. Paint objects can look the same whether they have visibility masks or not. However, a visibility mask changes the way that the Eraser tool works and the effect of deleting or moving a selection. Create options The Create Image dialog box has options for new images. File Size. The amount of memory required by the paint object, based on resolution, size, and image mode. Black & White mode requires the least memory; CMYK Color requires the most. Mode. Choose an image mode. See “Image modes for Canvas paint objects” on page 31.621. Background. Choose Trans- parent or Opaque. Opaque creates an image filled with opaque pixels. You can select a color from the adjacent palette. To specify a custom color, see “Creat- ing custom colors in pop-up palettes” on page 18.320. Transparent creates a clear image with a visibility mask. When you choose this option, the color palette is not available. Width and Height. Type the paint object’s width and height. In the adjacent menus, choose pixels and enter relative dimensions, or choose a unit of measure- ment and enter absolute dimensions. Res. Enter the image resolu- tion. Choose pixels per inch or pixels per centimeter in the adjacent menu. Auto. Click Auto to calculate the resolution based on half- tone screen frequency.
Canvas 8 Help: Painting and image-editing (5 of 46)                                                 Page #591