Metamerism, or the condition of paint color looking different in different light sources, can happen when paint is matched using light that is not color corrected. Most spray booths have light that is color corrected, which means that the booths have the same wavelengths as sun or white light. Light which is color corrected is measured by a color rendering index or CRI, and must be at least 85 to 92% CRI to properly match colors. If paint colors are compared under fluorescent light, which has more violet and reds in it, the colors will not match when viewed outside. This effect occurs because incandescent light contains more yellow, orange, and reds than sunlight or CRI corrected light.