Formulas
Exposure - Distance:
Where:
E1 = Exposure at D1
E2 = Exposure at D2
D1 = Distance 1 from source
D2 = Distance 2 from source
More information:
Exposure-Distance Calculation
Reciprocity Law:
Where:
C1 = Current 1
C2 = Current 2
T1 = Time 1 at C1
T2 = Time 2 at C2
More information:
Current-Time Reciprocity Calculation
Film Density - Exposure:
Where:
Note: This is an approximation and is only valid for the straight line portion of the film characteristic curve. See more info section.
E1 = Exposure 1
E2 = Exposure 2
FD1 = Film Density at Exposure 1
FD2 = Film Density with Exposure 2
More information:
Film Density - Exposure Calculation
Geometric Magnification
Where:
Ix = Transmitted intensity
a = Distance from source to object
b = Distance from object to detector
More information:
Geometric Magnification Calculation
Indication Depth:
Where:
D = Defect depth from the film side of the part
t = Thickness of material
SD = Shift of defect image on the film
SM = Shift of surface marker on the film
More information:
Indication Depth Calculation
Attenuation:
Where:
IX = Transmitted intensity
IO = Original intensity
m = Linear attenuation coefficient
x = Distance in material or material thickness
More information:
Attenuation Calculation
Half-Value Layer
Where:
HVL = Half-value layer
m = Linear attenuation coefficient
More information:
Half-Value Layer Calculation
