TTL TTL, which stands for "Through the Lens," is a metering and exposure control system used in cameras, flashes, and lighting equipment to measure and regulate the amount of light reaching the camera's image sensor or film plane. In TTL metering systems, the camera evaluates the light levels and exposure settings through the lens (hence the term "Through the Lens") in real-time, using sensors or metering circuits to calculate the optimal exposure settings for the scene.
TTL metering allows cameras to automatically adjust the aperture, shutter speed, and ISO sensitivity to achieve proper exposure, ensuring that images are neither underexposed nor overexposed. TTL metering systems are commonly used in digital SLR cameras, mirrorless cameras, and dedicated flash units to facilitate accurate and consistent exposure control in various lighting conditions. |