Dose Course 2018_Flipping book

Calibration: Determination of the sensitometric curve

❑ The film calibration procedure consists in acquiring a set of single measurements of net

optical density NOD with the corresponding absorbed dose and obtaining a function

which relates NOD for a given dose, called the sensitometric curve. The NOD is obtained

by subtracting the average OD of a non-irradiated film to an irradiated film using

regions of interest ROIs of constant sizes and uniform field doses

OD =-log

(T) =-log

(I

/I)

10

10

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