Cool Lights - Digital Photo Pro | DigitalPhotoPro.com: "I know what you're thinking. LED and fluorescent, okay, I can see them as cool light sources. But HMI? Get real! Have you ever stepped close to a 24,000W HMI? Granted, a light of that magnitude does generate considerable heat, but we're looking at 'cool' here in terms of bang for the watts—energy and operating cost-efficiency relative to light output, as well as heat projection onto a set, not actual surface temperatures."