Exposure Time#

The Exposure Time camera feature specifies how long the image sensor is exposed to light during image acquisition.

To automatically set the exposure time, use the Exposure Auto feature.

Using the Feature#

Setting the Exposure Time#

To set the exposure time:

1. Set the ExposureMode parameter to Timed.
2. If available, set the ExposureAuto parameter to Off.

3. The next steps depend on your camera model:

   • To set the Exposure Time parameter for the whole image:

     1. Make sure that the ExposureTimeMode parameter is set to Common.
     2. Set the ExposureTime parameter to the desired exposure time in microseconds.

   • To set different exposure times for different stages (e.g., image lines):

     1. Set the ExposureTimeMode to Individual.
     2. Select the desired stage via the ExposureTimeSelector parameter.
     3. Set the ExposureTime parameter for the selected stage to the desired exposure time in microseconds.
     4. Repeat steps 2 and 3 for the other stages you want to specify.

The minimum and maximum exposure time vary by camera model.

Determining the Exposure Time#

To determine the current exposure time in microseconds:

• On ace 2 R/V/X, boost R, and dart R/M cameras, get the value of the BslEffectiveExposureTime parameter. This parameter is read-only. It takes factors like internal offsets or clock speed requirements into account that may cause the exposure time to differ from the exposure time set.
• On other cameras, get the value of the ExposureTime parameter. Note that depending on the sensor type and its specific characteristics, this value may differ slightly from the effective exposure time.

Determining the exposure time can be useful, for example, if the Exposure Auto auto function is enabled and you want to retrieve the automatically adjusted exposure time.

Exposure Time Mode#

On some camera models, the ExposureTimeMode parameter is available. It allows you to choose between exposure time modes that provide different exposure time ranges. Depending on your camera model, you can also set individual exposure times for different regions on the sensor, e.g., for two sensor lines or for red and green pixels.

You can set the ExposureTimeMode parameter to one of the following values:

• Common or Standard: Enables the Common or Standard exposure time mode. This is the default setting.
• Individual: Allows you to specify different exposure times for individual regions (Stage 1, Stage 2) on the image sensor. This can be useful, if you want to define different exposure times, e.g., for two sensor lines.
• Short: Allows you to set a short exposure time within the value range available.
• UltraShort: Allows you to set an ultra short exposure time within the value range available.

Exposure Time Selector#

On some camera models, the ExposureTimeSelector parameter is available. It allows you to expose either the entire image sensor for the exposure time specified or individual regions (Stage 1, Stage 2)on the image sensor.

You can set the ExposureTimeSelector parameter to one of the following values:

• Common: The entire image sensor is exposed for the exposure time specified.
• Stage 1: Stage 1 is exposed for the exposure time specified. Stage 1 is a predefined region on the image sensor.
• Stage 2: Stage 2 is exposed for the exposure time specified. Stage 2 is a predefined region on the image sensor.

Specifics#

Show all camera models

Additional Information for ace Classic Cameras#

Table 1#

The following table applies to acA2040-90uc/um/umNIR and acA2000-165uc/um/umNIR cameras using an 8-bit pixel format.

Table 2#

The following table applies to the indicated camera models when operated in Global Reset Release shutter mode.

Example: Assume you are operating an acA3800-10gm camera in Global Reset Release shutter mode. You set the exposure time to 1000 µs. The effective exposure time is 1000 + 5218 = 6218 µs.

Sample Code#

ace Classic/U/L GigE Cameras#

// Determine the current exposure time
double d = camera.ExposureTimeAbs.GetValue();
// Set the exposure time to 3500 microseconds
camera.ExposureTimeAbs.SetValue(3500.0);

INodeMap& nodemap = camera.GetNodeMap();
// Determine the current exposure time
double d = CFloatParameter(nodemap, "ExposureTimeAbs").GetValue();
// Set the exposure time to 3500 microseconds
CFloatParameter(nodemap, "ExposureTimeAbs").SetValue(3500.0);

// Determine the current exposure time
double d = camera.Parameters[PLCamera.ExposureTimeAbs].GetValue();
// Set the exposure time to 3500 microseconds
camera.Parameters[PLCamera.ExposureTimeAbs].SetValue(3500.0);

/* Macro to check for errors */
#define CHECK(errc) if (GENAPI_E_OK != errc) printErrorAndExit(errc)
GENAPIC_RESULT errRes = GENAPI_E_OK;  /* Return value of pylon methods */
double d = 0;
/* Determine the current exposure time */
errRes = PylonDeviceGetFloatFeature(hdev, "ExposureTimeAbs", &d);
CHECK(errRes);
/* Set the exposure time to 3500 microseconds */
errRes = PylonDeviceSetFloatFeature(hdev, "ExposureTimeAbs", 3500.0);
CHECK(errRes);

# Determine the current exposure time
d = camera.ExposureTimeAbs.Value
# Set the exposure time to 3500 microseconds
camera.ExposureTimeAbs.Value = 3500.0

ace 2, boost, dart M/R, and racer 2 Cameras#

// Determine the current exposure time using Exposure Time
double d = camera.ExposureTime.GetValue();
// Determine the current exposure time using Effective Exposure Time
double d = camera.BslEffectiveExposureTime.GetValue();
// Set the exposure time mode to Common
camera.ExposureTimeMode.SetValue(ExposureTimeMode_Common);
// Set the exposure time to 3500 microseconds
camera.ExposureTime.SetValue(3500.0);

INodeMap& nodemap = camera.GetNodeMap();
// Determine the current exposure time using Exposure Time
double d = CFloatParameter(nodemap, "ExposureTime").GetValue();
// Determine the current exposure time using Effective Exposure Time
d = CFloatParameter(nodemap, "BslEffectiveExposureTime").GetValue();
// Set the exposure time mode to Common
CEnumParameter(nodemap, "ExposureTimeMode").SetValue("Common");
// Set the exposure time to 3500 microseconds
CFloatParameter(nodemap, "ExposureTime").SetValue(3500.0);

// Determine the current exposure time using Exposure Time
double d = camera.Parameters[PLCamera.ExposureTime].GetValue();
// Determine the current exposure time using Effective Exposure Time
d = camera.Parameters[PLCamera.BslEffectiveExposureTime].GetValue();
// Set the exposure time mode to Common
camera.Parameters[PLCamera.ExposureTimeMode].SetValue(PLCamera.ExposureTimeMode.Common);
// Set the exposure time to 3500 microseconds
camera.Parameters[PLCamera.ExposureTime].SetValue(3500.0);

/* Macro to check for errors */
#define CHECK(errc) if (GENAPI_E_OK != errc) printErrorAndExit(errc)
GENAPIC_RESULT errRes = GENAPI_E_OK;  /* Return value of pylon methods */
double d = 0;
/* Determine the current exposure time using Exposure Time */
errRes = PylonDeviceGetFloatFeature(hdev, "ExposureTime", &d);
CHECK(errRes);
/* Determine the current exposure time using Effective Exposure Time */
errRes = PylonDeviceGetFloatFeature(hdev, "BslEffectiveExposureTime", &d);
CHECK(errRes);
/* Set the exposure time mode to Common */
errRes = PylonDeviceFeatureFromString(hdev, "ExposureTimeMode", "Common");
CHECK(errRes);
/* Set the exposure time to 3500 microseconds */
errRes = PylonDeviceSetFloatFeature(hdev, "ExposureTime", 3500.0);
CHECK(errRes);

# Determine the current exposure time using Exposure Time
d = camera.ExposureTime.Value
# Determine the current exposure time using Effective Exposure Time
d = camera.BslEffectiveExposureTime.Value
# Set the exposure time mode to Common
camera.ExposureTimeMode.Value = "Common"
# Set the exposure time to 3500 microseconds
camera.ExposureTime.Value = 3500.0

Other Cameras#

// Determine the current exposure time
double d = camera.ExposureTime.GetValue();
// Set the exposure time to 3500 microseconds
camera.ExposureTime.SetValue(3500.0);

INodeMap& nodemap = camera.GetNodeMap();
// Determine the current exposure time
double d = CFloatParameter(nodemap, "ExposureTime").GetValue();
// Set the exposure time to 3500 microseconds
CFloatParameter(nodemap, "ExposureTime").SetValue(3500.0);

// Determine the current exposure time
double d = camera.Parameters[PLCamera.ExposureTime].GetValue();
// Set the exposure time to 3500 microseconds
camera.Parameters[PLCamera.ExposureTime].SetValue(3500.0);

/* Macro to check for errors */
#define CHECK(errc) if (GENAPI_E_OK != errc) printErrorAndExit(errc)
GENAPIC_RESULT errRes = GENAPI_E_OK;  /* Return value of pylon methods */
double d = 0;
/* Determine the current exposure time */
errRes = PylonDeviceGetFloatFeature(hdev, "ExposureTime", &d);
CHECK(errRes);
/* Set the exposure time to 3500 microseconds */
errRes = PylonDeviceSetFloatFeature(hdev, "ExposureTime", 3500.0);
CHECK(errRes);

# Determine the current exposure time
d = camera.ExposureTime.Value
# Set the exposure time to 3500 microseconds
camera.ExposureTime.Value = 3500.0

You can also use the pylon Viewer to easily set the parameters.