A camera flash emits light with a color temperature of about 5500 K.
When discussing how "hot" a camera flash gets, it's important to distinguish between the color temperature of the light produced and the actual physical temperature of the flash tube itself. The provided reference specifically refers to the color temperature.
According to the reference, a flash is a device used in photography that produces a brief burst of light (lasting around 1⁄200 of a second) at a color temperature of about 5500 K to help illuminate a scene. The main purpose of a flash is to illuminate a dark scene.
Color Temperature Explained
Color temperature is a characteristic of visible light. It describes the color appearance of the light source itself, measured in Kelvin (K).
- A lower Kelvin number (e.g., 2700 K) indicates warmer, more reddish-yellow light (like an incandescent bulb).
- A higher Kelvin number (e.g., 6500 K) indicates cooler, more bluish light (like an overcast sky).
- A color temperature of around 5500 K is considered to be very close to the color of daylight around noon on a clear day.
Color Temperature vs. Physical Temperature
It's crucial to note that color temperature is not the physical temperature of the light source, although they are related, especially for theoretical blackbody radiators. The actual physical temperature of the flash tube during discharge gets very hot due to the electrical energy passing through the gas, but this specific physical temperature is not given in the reference. The 5500 K figure refers solely to the color quality of the light emitted.
Why 5500 K is Important
The choice of approximately 5500 K for camera flashes is deliberate:
- Daylight Balance: This color temperature closely matches typical daylight, which is the standard reference for color in photography.
- Accurate Colors: Using a flash with a color temperature near daylight helps ensure that the colors in a photograph appear natural and accurate, without an unnatural warm or cool cast, especially when used as the primary light source or mixed with natural daylight.
- Consistency: Provides a consistent light quality for photographers regardless of external lighting conditions.
In summary, while the physical flash tube gets hot from the energy discharge, the specification of "how hot" in the context of the light it produces refers to its color temperature, which is approximately 5500 K.
