Exposure Absolute Values

Blogged by Stefan Geißler on March 31, 2008.

Very often, I am asked how to access the Absolute Values interface of the exposure time. Although this seems to be complicated at first glace, it is not:

The interface is accessed in the following three steps:

Declare the necessary variables for the interfaces.
Query the interfaces.
Work with the queried interfaces.

Declare the variables for the interfaces

We need a variable for the interface to toggle automatic exposure and a variable for the exposure values interface.

VB:

Dim AbsoluteValues As ICImagingControl3.VCDAbsoluteValueProperty
Dim ExposureAuto As ICImagingControl3.VCDSwitchProperty

C#:

using TIS.Imaging;
ICImagingControl3.VCDAbsoluteValueProperty AbsoluteValues;
ICImagingControl3.VCDSwitchProperty ExposureAuto;

Query the interfaces

This step is quite simple. The only thing you have to do is gather the required information:

VB:

AbsoluteValues = IcImagingControl1.VCDPropertyItems.FindInterface( 
                                           VCDIDs.VCDID_Exposure + ":" + _
                                           VCDIDs.VCDElement_Value + ":" + _
                                           VCDIDs.VCDInterface_AbsoluteValue)

ExposureAuto = IcImagingControl1.VCDPropertyItems.FindInterface( 
                                           VCDIDs.VCDID_Exposure + ":" + _
                                           VCDIDs.VCDElement_Auto + ":" + _
                                           VCDIDs.VCDInterface_Switch)

C#:

AbsoluteValues = (ICImagingControl3.VCDAbsoluteValueProperty)icImagingControl1.VCDPropertyItems.FindInterface(
                                                     VCDIDs.VCDID_Exposure + ":" +
                                                     VCDIDs.VCDElement_Value + ":" +
                                                     VCDIDs.VCDInterface_AbsoluteValue);
                                                     
ExposureAuto = (ICImagingControl3.VCDSwitchProperty) icImagingControl1.VCDPropertyItems.FindInterface( 
                                                     VCDIDs.VCDID_Exposure + ":" +
                                                     VCDIDs.VCDElement_Auto + ":" +
                                                     VCDIDs.VCDInterface_Switch);

Work with the queried interfaces

Now we can check, whether the interfaces exist and query their values.

VB:

    'Disable automatic
If Not ExposureAuto Is  Nothing Then
	ExposureAuto.Switch = false
End If


If Not AbsoluteValues Is  Nothing Then
	Dim ExposureMin As Double
	Dim ExposureMax As Double
	Dim ExposureValue As Double

	' Query the currently set values:
	ExposureMax = AbsoluteValues.RangeMax
	ExposureMin = AbsoluteValues.RangeMin
	ExposureValue = AbsoluteValues.Value

	'Set a new exposure value
	AbsoluteValues.Value = 0.002
End if

C#:

// If ExposureAuto exposure exists ...
if (ExposureAuto != null)
{
	//... make sure, it is disabled.
	ExposureAuto.Switch = false;
}


// If the absolute values interface exists...
if (AbsoluteValues != null)
{
	double ExpMin, ExpMax, ExpCurrent;

	// ... query the currenty values:
	ExpMin = AbsoluteValues.RangeMin;
	ExpMax = AbsoluteValues.RangeMax;
	ExpCurrent = AbsoluteValues.Value;

	//.. set a new value
	AbsoluteValues.Value = 0.001;

}