A number of variables may affect the ability of students to perceive, and learn from, instructional materials. The objectives of the study presented here were to determine the projected color that provided the best visual acuity for the viewer, and the necessary minimum exposure time for achieving maximum visual acuity. Fifty volunteers--undergraduate students at Duquesne University in Pittsburgh--participated in the study. All subjects were given eye examinations for visual acuity and color deficiency (Graham-Field Acuity Test and Ishihara Color Vision Test), and Kodak photography equipment was used to project a series of 208 stimulus slides with black backgrounds which were randomly presented at both pre-set and subject-controlled intervals. Each series of slides varied in the color of the symbols and the symbol gap direction, and three different hues of four colors representing the widest portion of the visible spectrum--red, blue, green, and yellow--were used. The findings indicated that white is the best color to use when designing instructional materials, followed by middle yellow, dark yellow, light yellow, light blue, middle red, light green, dark red, dark blue, middle blue, middle green, and dark green; the longer the amount of time a visual is on a screen the more likely it is to be seen; and, in general, a subject's ability to corrrectly perceive a message, regardless of color, increases as the time of presentation of the message increases. (CGD)