Brightness of taken subject, unit is APEX. To calculate Exposure(Ev) from BrigtnessValue(Bv), you must add SensitivityValue(Sv).

Ev=Bv+Sv Sv=log2(ISOSpeedRating/3.125)

ISO100:Sv=5, ISO200:Sv=6, ISO400:Sv=7, ISO125:Sv=5.32.

Namespace: HiComponents.IEvolution
Assembly: IEvolution2 (in IEvolution2.dll) Version: 10.1.0.0

Syntax

         
 C#  Visual Basic  Visual C++ 
public double EXIF_BrightnessValue { get; set; }
Public Property EXIF_BrightnessValue As Double
	Get
	Set
public:
property double EXIF_BrightnessValue {
	double get ();
	void set (double value);
}

See Also