33
The measurement formula
Figure 33.3 Relative magnitudes of radiation sources under varying measurement conditions (LW cam-
era). 1: Object temperature; 2: Emittance; Obj: Object radiation; Refl: Reflected radiation; Atm: atmos-
phere radiation. Fixed parameters: τ = 0.88; T
= 20°C (+68°F); T
= 20°C (+68°F).
refl
atm
98
#T559772; r.7877/7877; en-US