Lamp is a general photographic term used to describe the wide variety of artificial light sources employed in photography, both in the studio and on location. The term encompasses a broad range of light producing devices, from simple domestic tungsten bulbs used in basic lighting setups through to highly specialised professional light sources designed specifically for photographic and cinematographic applications.
In photographic usage, the term lamp can refer to several distinct types of artificial light source, each with its own characteristics in terms of colour temperature, light output, power consumption, and suitability for different applications. Tungsten lamps, which produce a continuous warm toned light at a colour temperature of around 3200 Kelvin, were for many decades the standard artificial light source in photographic and film studios, valued for their consistency, controllability, and the ability to see and adjust the quality of the light before shooting. Tungsten halogen lamps, an evolution of the basic tungsten design, offer a longer working life and more consistent colour temperature throughout their lifespan.
Fluorescent lamps, HMI lamps, and LED light sources represent further categories of continuous artificial lighting used in photography and filmmaking, each offering particular advantages in terms of colour quality, energy efficiency, heat output, and daylight balanced colour temperature. Flash lamps - the discharge tubes used in electronic flash units and studio flash heads - are also referred to as lamps in a photographic context, producing an intense but extremely brief burst of daylight balanced light that is the preferred light source for the majority of professional still photography.
The choice of lamp type has a direct influence on the colour balance of the final image, as different lamp types emit light at different colour temperatures. Matching the camera's white balance setting to the colour temperature of the lamp being used - or applying appropriate filtration - is essential to achieving accurate and consistent colour reproduction across different lighting situations.