the.com/radiometry
Measuring light like a strict accountant, counting every photon's energy, no vibes allowed.
means The science of measuring the power or intensity of electromagnetic radiation, especially light, using physical units of energy rather than how bright it appears to the eye.
from Built from Latin 'radius' (a ray, a spoke of a wheel) plus Greek '-metron' (measure). 'Radius' spread into English as both the geometric term and the root of 'radiation,' while '-metry' is the same measuring suffix found in 'geometry' and 'photometry.' The word itself is a fairly modern technical compound, assembled once scientists needed to distinguish objective energy measurement (radiometry) from human-perceived brightness (photometry) — the accountant's ledger versus the eye's opinion.
- vs photometry
- ignores human eyes, measures all wavelengths equally
- core units
- watts, not lumens, pure physical power
- used in
- satellites, thermal cameras, astronomy, climate monitoring
- blind spot
- cannot tell if light looks bright to you