User Guide

Chapter 5: Painting And Image Editing
Using TWAIN-compatible scanners
Scanner manufacturers created the TWAIN interface to standardize interaction between scanners
and computer software. Scanners that comply with the TWAIN standard provide a “source manager”
file, which translates scanner information into data that Canvas can use. You must install the TWAIN
scanner software on your system before you can select the scanner and scan images in Canvas.
If you aren’t sure whether a scanner is TWAIN-compatible, consult the scanner documentation or
contact the manufacturer.
To select a TWAIN scanner:
1. Choose Image | TWAIN Import | Select Scanner. In the Select Source dialog box, a scrolling
list contains the names of all TWAIN scanners for which Canvas can locate a data source.
2. Select the scanner you want to use and click OK. The Select Source dialog box closes and the
scanner you selected becomes the active scanner.
To acquire images using a TWAIN scanner:
1. When you scan an image, it appears in the active Canvas document. Open an existing
document or choose File | New to create a new document.
2. Choose Image | TWAIN Import | Acquire Image.
3. In the dialog box, select the options you want to use.
Click Prescan to view a preview of the image. You can verify that the image is aligned and
completely visible and reposition it if necessary.
Depending on the available options, you can adjust scaling and brightness of the image.
4. Click Scan to begin scanning. When the scanner finishes, the scanned image appears in the
active Canvas document.
Choosing a scanning resolution
Digital images are composed of square pixels, and pixel size is a major factor affecting image quality.
The resolution of an image is expressed as the number of pixels per (linear) inch (ppi), or pixels per
centimeter. Smaller pixels result in higher image resolution, which generally indicates better image
quality. With scanned images, the resolution is also a measure of how much information has been
captured from the original artwork.
At relatively low resolution, such as 75 ppi, lines, edges, and character shapes in an image can
appear jagged (see "About digital images and resolution" on page 448).
Use the following questions to help you decide an appropriate resolution when you scan images.
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