Black Mist / Pro Mist
Lens & optics
A diffusion filter that softly bloomes highlights and reduces contrast for a cinematic look.
Tiny particles in the glass spread bright light: lamps grow a halo, skin looks softer, dark areas lift slightly. Tiffen Black Pro-Mist (1/8, 1/4, 1/2, 1) is the best-known, NiSi Allure Mist and K&F Pro Mist are affordable alternatives. Popular for video and portrait. Too strong and the image looks hazy; 1/4 or 1/8 is usually enough for stills. Software can approximate the effect, but in-camera it looks more natural.
Tools that help with this: