A rotary control (120) is illuminated through a controlled illuminated indicator provided by a light guide arc reflector (114) disposed on a control panel (104) along an outer periphery of a rotary control knob (112). The controlled illuminated indicator concurrently indicates status and location of the rotary control knob. The controlled illuminated indictor generates an increased rotational arc of illumination in response to the knob being rotated in a first direction and generates a decreased rotational arc of illumination in response to the knob rotated in a second direction. The rotary control (120) utilizes a helix slider (304) to control upwards and downwards movement of a reflector shield (302) which block and unblocks light rays in response to the knob (112) being rotated.