My favourite subject, canoeing... I mean, raster graphics.

When I look at these raster images of great places to canoe, a voice starts to ask, "what are you doing in front of this computer, why aren't you out there paddling?"

The voice has a point. But we need to get through this page on raster graphics first. Maybe later we can devote an entire page to canoeing, and call it, euphemistically, "Other Interests".

Raster graphics, you will recall, are the other way that computers have to express graphic information.

(Another name for "raster graphics" is "bitmap images". These terms can be used interchangeably.)

Instead of defining entire shapes and assigning them location and colour, as in vector graphics, raster graphics divide a picture into many square-shaped dots called pixels.

Each pixel is assigned a specific colour, and when assembled like a mosaic, the pixels form an image.

The more pixels there are, the more convincing and precise the image appears. Of course, more pixels also require more data.

Raster graphics excel at conveying a sense of tangible, natural reality. They literally mimic how we see the world around us, with all its subtlety and ambiguity.

The way my mind wandered earlier attests to the evocative power of raster graphics in illustration.

Working in a raster environment involves skillful and imaginative editing of imported information. The available editing tools are powerful and can be exciting to use.

Computer applications that produce raster graphics are called painting programs or image editors. I use Adobe Photoshop^® for my work.

Perhaps raster graphics is my favourite subject after all, as fond as I remain of canoeing.