Calibrated against macOS 26 Control Center: glass_L = 0.58 × backdrop_L + 34
Light blur, thin neutral scrim. For glass over media that should stay readable.
The measured variant — Control Center is Apple's regular glass, so these are the numbers the fit came from.
Larger surfaces: deeper shadow, wider rim, full #lg-refract lensing.
The 35% dimming layer the HIG prescribes for clear glass over bright media.
Lion Nebula (NIRCam and MIRI) · NASA, ESA, CSA