A large area lighting system, adapted for high mast highway or stadium lighting, for example, includes one or more elongated frames supporting plural light fixtures and elongated light baffles comprising respective sets of spaced apart slats. The respective sets of slats are supported on elongated rods connected to light fixture frame members and the slats are separated by spacers sleeved over the rods. The slats may be oriented at various angles by manual or motor driven adjustment to control the light projection from the lighting system. The slats may also be non-reflective or provided with a mirrored finish to effect control of light projection and/or diffusion.