Grayscale vs Black-only Line Art
A grayscale image is a black and white image with shades of gray. Black would be the darkest shade of gray and white the lightest shade with many shades of gray in between. A vectorized grayscale image can include soft highlights and shadows. A black and white photograph is a sample of a grayscale image.
Line art is an image that consists of lines without any gradation of shade or color. Areas of solid pigment and dots can also be used in addition to lines. Line art can use lines and objects of different colors, although line art is usually monochromatic.
When preparing line-art using spot colors this would also mean 100% of each solid spot color:
- No percentages of color
- No soft highlights, no soft shadows
- No color gradients, no color blends
- No shades of color
- No fading color
- No halftones
Vectorizing a Grayscale Image
Depending on the process your vector file will be used for, your original grayscale image may be vectorized as a grayscale image or it may need to be changed to line art.
Vector programs enclose each color, or with grayscale images each shade of gray, within a separate "object". I've vectorized this grayscale image and added a red outline around each different shade of gray so that the objects are visible.
The vectorized grayscale image has a multitude of different color objects, too many for certain processes. For example, for vinyl-cut signs, sign makers would need to cut each object out, this image is too complex for this particular project. A simplified vector line art version would work better. Other processes that require vector line art would be engraving, specialty printing, and plotters.
Ask your supplier whether they can use a vector grayscale image or whether you need to provide vector line art. If your original image is grayscale or multi-tone and your new vector image will be used for many different projects, it would probably be a good idea to have two versions of your image; full color/grayscale, and line art format.