A flash meter is a specialized light meter used to measure the intensity of light emitted from an electronic flash or studio lighting setup. By measuring the flash output, the meter can suggest the appropriate aperture and camera settings to achieve correct exposure for a photograph.
Some flash meters are designed solely for flash photography, while others are multipurpose, capable of measuring ambient light as well. Professional photographers often use flash meters in studio and location shoots to ensure consistent and balanced lighting, helping to avoid underexposed or overexposed images and achieve high-quality, well-lit photographs.