How much of what an unfiltered sensor records is invisible
Drawn at its defaults, in cameras, sensors and reproduction. It takes 3 options, and the essays below show what each placement asks of it.
Called by 3 essays
the blast radius of changing it
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.
What a camera doesMost things are pale in the infrared
A spectrophotometer stops at 780 nanometres and a black cotton shirt reflecting five per cent of visible light reflects more than half the near infrared. The measurement everybody has and the quantity a camera integrates are different quantities, and nothing in the first says so.
What a camera doesThe grid outside every figure
Every figure here is computed on 380 to 780 nanometres, which is exactly right for an eye and insufficient for a sensor. This field met the first subject the grid cannot hold, and the decision was not to widen it — because widening it honestly is impossible.