midlight

Midlight is a term used in lighting design and color theory to describe an intermediate level of ambient illumination that sits between bright daylight and dim interior lighting. It refers to moderate luminance with diffuse, even distribution and minimal glare. The concept is often employed to create visual comfort and to serve as a neutral reference condition in imaging and display calibration.

Origin and usage: The term has appeared in architectural lighting literature and in discussions of color rendering, though it is not a standardized technical term in major standards bodies. It is typically used informally to describe interior lighting scenarios that resemble late morning to early afternoon outdoors but softened to reduce contrast.

Spectral and color characteristics: Midlight commonly involves color temperatures in the mid-range (roughly 4000–5500 kelvin) with a color rendering index comparable to daylight or higher, ensuring faithful color reproduction under diffuse illumination. The spectrum tends to be balanced across wavelengths with a lack of extreme color bias.

Applications: In architectural design, midlight informs layout planning, material selection, and glare management. In photography and film, it functions as a reference for exposure settings under diffuse daylight-mimicking conditions. In digital imaging and display calibration, midlight serves as a mid-range ambient reference to balance dynamic range and color accuracy.

Limitations: As a nonstandard term, midlight definitions vary by field and project. It does not replace established lighting metrics such as illuminance, color temperature, or CRI.

See also: ambient light, daylight, twilight, color temperature, CRI.