Popularly referred to as energy-saving lamps, compact fluorescent lamps have a poor image because of perceived deficiencies in colour, power and speed to full output. But massive improvements have been made in all these areas thanks to substantial investment by the big lamp manufacturers.
IRC halogen lamps are sources where the central halogen burner has been coated with an infra-red coating (hence IRC). This reflects the infra-red energy back onto the tungsten burner, which means it heats up and becomes more efficient as much of the reflected heat energy is turned into visible light.
Colour gamut is a measure of how colourful a scene will appear under a given light source. Sources with a high colour gamut generally make objects appear brighter and more colourful.