When sewing or writing have the light at your left, unless you are left-handed. This is to keep the shadow of your hands from the work.
Avoid a glare or light that is in streaks or bars of alternate dark and bright. Diffused, even light is best.
Have your eyes examined by a competent oculist immediately:
If you have headaches,
If the eyes sting or burn after using,
If print or other objects dance or blur,
If you must get close to your work to see it,
If near work tires your eyes or you,
If there is the slightest irritation or soreness about the lids or other parts.
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