Mired
A unit of reciprocal colour temperature that makes colour shifts uniform in perceptual terms, used to specify filters and gels.
Formula / rule
mired = 1,000,000 / K
Measured in
mired
In depth
A hundred-kelvin change is enormous at 2000 K and invisible at 9000 K, so kelvin is a poor unit for describing corrections. Mireds fix this: a given mired shift produces the same visual change anywhere on the scale, which is why colour correction filters are rated in mired shift values rather than kelvin.
Examples in practice
A full CTO gel has a shift of about +131 mired, taking 5500 K light down to roughly 3200 K.