Exposure Time#

相机的 Exposure Time 功能指定在图像采集期间，图像传感器暴露于光线下的时间。

要自动设置曝光时间，请使用 Exposure Auto 功能。

该功能的使用#

确定曝光时间#

确定当前的曝光时间（以微秒为单位）：

• 在 ace 2, 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.
• 在 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.

曝光时间模式#

在 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 参数设置为以下值：

• Common 或 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 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#

在 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 on the image sensor.

You can set the ExposureTimeSelector 参数设置为以下值：

• 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.

Interleaved HDR#

Basler ace 2 R mono cameras with the sensors GMAX2505, GMAX2509, and GMAX2518 support interleaved HDR (iHDR). The iHDR feature allows you to set different exposure times for even and odd pixel lines of the sensor to increase the dynamic range of the final image.

To set the exposure time for iHDR:

1. 设置 ExposureTimeMode parameter to Individual.
2. 设置 ExposureTimeSelector parameter to Stage 1.
3. Specify the exposure time for stage 1.
   The value specified for stage 1 applies to the even pixel lines of the sensor.
4. 设置 ExposureTimeSelector parameter to Stage 2.
5. Specify the exposure time for stage 2.
   The value specified for stage 2 applies to the odd pixel lines of the sensor.

For example, you can specify a long exposure time for lines 1, 3, 5, etc. and a reduced exposure time for lines 2, 4, 6, etc. The long and short exposures start simultaneously. This creates a "striped" image with bright and dark lines.

Use an external post-processing program to combine the bright and dark lines to generate a high dynamic range image.

设置曝光时间#

要设置曝光时间：

1. 设置 ExposureMode parameter to Timed.
2. 如果可用，请设置 ExposureAuto parameter to Off.
3. 设置 ExposureTimeMode parameter (如果可用) to the desired exposure time mode.

4. 设置 ExposureTimeSelector parameter (如果可用) to the sensor region that should be exposed.

   信息

   To be able to specify exposure times for different regions, the ExposureTimeMode parameter must be set to Individual.

5. 设置 ExposureTime parameter to the desired exposure time in microseconds.

6. If necessary, repeat steps 4 and 5 for every region for which you want to specify individual exposure times.

最短和最长曝光时间因相机型号而异。

详情#

显示所有相机型号

有关 ace Classic 相机的其他信息#

表 1#

下表适用于使用 8 位 pixel format 的 acA2040-90uc/um/umNIR 和 acA2000-165uc/um/umNIR 相机。

表 2#

下表适用于在全局重置释放 shutter mode 下操作的指定相机型号。

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.

示例代码#

ace Classic/U/L GigE 相机#

// 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, and dart M/R 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

其他相机#

// 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

您也可以使用 pylon Viewer 轻松设置参数。