Is it better to adjust the television set to room lighting or room lighting to the set?

Adapt the set's brightness and contrast to room lighting -- not room lighting to the set -- after the room lights have been turned on.

Is it all right to wear sunglasses while watching television?

Generally, no. Sunglasses may shut out too much light for good vision. If worn when not needed, they tend to make it difficult for the viewer to adapt promptly to normal light. If you are bothered by brightness, consult with an eye care practitioner about the possible need for lenses more appropriate to TV viewing.

What about color television for viewers with color vision deficiencies?

Color deficiency (i.e. color blindness) is generally not a barrier to enjoying color television. However, viewers with color deficiencies may disagree with others as to the "proper" color adjustment. A color TV picture properly adjusted for most people may appear too green to a protanomalous (weak red) observer, or too red to a deuteranomalous (weak green) viewer. When the set is adjusted to "correct" its color, the resulting picture is usually unsatisfactorily tinted for other viewers. Viewers who are severely color deficient, the so-called "red blind" or "green blind," will see little or no difference in widely different color mixtures, and will not be bothered by most color adjustments.