User Guide

Chapter 5: Painting And Image Editing
Black & White image mode
Black & White image mode is used for scanned line art and black-and-white (“bitmap”) images,
which contain only black and white pixels. Images in Black & White mode require the least amount of
memory and disk space.
To convert to Black & White mode:
Grayscale mode images and Multichannel mode images are the only images you can directly convert
to Black & White mode. If an image is not Grayscale, convert it to Grayscale mode first if you want to
convert it to Black & White mode.
1. Select the paint objects and use the Image Mode menu on the Properties bar or choose Image
| Mode | Black & White. The Select Halftone Method dialog box lets you choose a conversion
option.
2. Select one of the following:
Pattern Dither: Canvas “screens” the image, rendering its tones as patterns of tiny
dots, using a fixed pattern similar to a traditional halftone screen
Diffusion Dither: Canvas “screens” the image, rendering its tones as patterns of tiny
dots, using a process that creates a random pattern effect.
Threshold: Canvas converts the image to a high-contrast, black-and-white image. Pixels
of lightness values from 0 to 128 become black, and pixels of lightness values from 129
to 255 become white.
3. Click OK.
When you paste a selection into a Black & White image, Canvas uses diffusion dither on the
selection.
Grayscale image mode
Grayscale mode is appropriate for images scanned from black & white photographs or when the
image will never be printed in color. In Grayscale mode, pixels use 256 brightness levels to represent
a range of shades from pure black to pure white. Grayscale uses 8 bits per pixel and requires less
memory than most color modes.
If you convert a color image to Grayscale mode, Canvas discards all color information.
437