Colour Science & Perception
what the eye settles, and what it cannot
Generator

The red channel, as the three things multiplied to make it

Silicon's quantum efficiency, the colour-filter dye's transmittance, the infrared-cut filter, and their product. The dye is the only stage carrying any colour information and it is clear above about 800 nm — transmittance 0.92 at 900 nm against 0.66 at 550.
The red channel, as the three things multiplied to make it. Silicon's quantum efficiency, the colour-filter dye's transmittance, the infrared-cut filter, and their product. The dye is the only stage carrying any colour information and it is clear above about 800 nm — transmittance 0.92 at 900 nm against 0.66 at 550.

Drawn at its defaults, in cameras, sensors and reproduction. It reads 2 options and no others: channel, irCut.

Called by 3 essays

the blast radius of changing it

What a camera does

A camera is a fourth observer

The 1931 functions, the 1964 functions and a person's own cones are three sets of three curves that collapse a spectrum onto three numbers. A camera is a fourth, built from silicon and dye rather than from pigment and neural wiring, and it agrees with none of them.

 What a camera does

Silicon sees past the visible

A sensor's response ends at 1107 nanometres because that is the band gap, and the colour-filter dyes have stopped absorbing three hundred nanometres before it. So all three channels measure the same thing over the last third of the range, and every published sensitivity plot is drawn after the component that hides it.

 What a camera does

The filter that makes colour possible

An infrared-cut filter is not a refinement on a colour camera. Removing it collapses the separation between the three channels by a factor of nearly nine under tungsten, and the component that keeps colour photography working is the one nobody photographs.

All 155 generators · what each essay asks for instead