External monitor

If you use an external monitor, this suggestion may be helpful.
nIf possible, arrange the monitor so the top of the screen is
slightly below your eye level when you’re sitting at the
keyboard. The best distance from your eyes to the screen is
up to you, although most people seem to prefer 18 to 28
inches (45 to 70 cm).

Avoiding fatigue

nChange your seated position, stand up, or stretch whenever
you start to feel tired. Frequent short breaks are helpful in
reducing fatigue.
nAllow adequate workspace so that you can work comfortably.
Place papers or other items so you can view them easily while
using your computer. A document stand may make reading
papers more comfortable.
nEye muscles must work harder to focus on nearby objects.
Occasionally focus your eyes on a distant object, and blink
often while you work.
nClean your screen regularly. Keeping the screen clean helps
reduce unwanted reflections.
Chapter 1: Setting Up Your PowerBook Duo 25