IDS Software Suite 4.96.1

Shutter modes

The following table displays the four shutter modes and their advantages and disadvantages in different situations:

•The rolling shutter mode offers a better signal/noise ratio and a more consistent black level compared to the global shutter mode.

•If the sensor is used in global shutter mode at a low pixel clock frequency and a high gain, the bottom pixel rows might become brighter for technical reasons. Color distortion will occur for the color sensor with active white balance. In this case, use a higher pixel clock frequency, less gain or the rolling shutter mode.

•The "Global shutter (alternative timing)" mode offers a more consistent black level compared to the global shutter mode. This mode should not be used with a frame rate below 2 fps. This mode is also not suitable for bright, moving image contents in combination with long exposure times.

•If you switch from rolling shutter to the "Global shutter (alternative timing)" mode in software trigger mode, a noticeable image noise may be visible in the first image after switching.

•The rolling shutter mode with global start is suitable for capturing moving objects with flash.

•When using flash in rolling shutter mode make sure to set the flash duration accordingly ((1/maxFramerate) + exposure) or that the global time window is available by a long exposure time (2 * (1/MaxFramerate) + FlashDuration). For flashing into this time window use the flash delay (1/MaxFramerate).

•When changing the shutter mode, the flash parameters are only safely applied with the second image.

•In global shutter mode the shutter efficiency of 1:3000 have a negative impact with bright conditions and the usage of exposure times under 100 µs. In this case, set the pixel clock to the maximum possible value and close the aperture a little bit. Also enabling the Log mode with low values achieve huge improvements.

Black level

•The black level can also be set to negative values. Therefore, the factory setting of the offset control is nearly in the middle of the range.

•Use of the gain functions can lead to slight fluctuations of the black level.

•In global shutter mode the black level can also vary slightly between two image captures.

•When enabling the rolling or global shutter mode the black level is set to a fixed factory-provided value. Therefore, the black level can individually adjusted after switching the shutter mode.

•Depending on the internal black level and shutter mode the offset control shows no additional cumulative effect at the top.

•The factory setting of the offset control are so selected that the black level is always slightly increased to avoid losing image information by cutting underneath the origin. For linearity measurements the black level must be adjusted to the origin with the offset control before the measurement is done.

Color sensor

•Automatic black level correction is always enabled.

•The RGB gains work digital.

•The fast line scan mode is disabled.

NIR sensor

•It is recommended to use a IR-coated and IR-corrected high-quality lens, especially for non-monochromatic light.

•In the high IR wavelength range picture blur can occur with strong contrasts. This reduced MTF (modulation transfer function) is a characteristic of the sensor pixels.

•The master gain of the NIR sensor is adapted in comparison to the monochrome sensor. If both sensors are compared directly, the gain of the NIR sensor must be set to the double factor of the monochrome sensor. This can be done via the master gain or the gain boost.

•In the Log mode the guaranteed dynamic range of the NIR sensor is reached with a gain value of at least 1. For the monochrome sensor you need at least a value of 3. With very short exposure times, lower values can result in even higher dynamics.

•The two left image columns and the two bottom image lines might be slightly darker.

Gain, pixel clock

•Master gain uses a combination of coarsely scaled analog gain factors and finer digital scaling. To achieve optimum homogeneity of the gray level, use only the gain factors 0, 33, 66, and 100.

•The gain boost has the factor 2. When using the master gain a maximum factor of 8 is possible caused by the sensor.

•It is not recommended to use the gain boost along with the maximum master gain. With active gain boost it is only possible to set the master gain to 99 %.

•The minimum exposure time of 9 µs does not depend on the pixel clock.

•For global shutter mode the pixel clock should be set to the maximum possible value to increase the image quality.

•In the 10 bit mode the usage of the digital gain intermediate level produces missing pixel values as the sensor works internally with maximally 10 bit.

Hot pixel

•In the rolling shutter mode, there are less hot pixels, as the pixel charges are not buffered in the sensor.

•The sensor corrects hot pixels dynamically. Neighbored hot pixels in diagonal direction cannot be corrected effectively. These positions are covered by the factory-made hot pixel correction and are eliminated by the software hot pixel correction. Therefore, the hardware hot pixel correction is a prerequisite and should not be deactivated.

•On the color sensor the hot pixel correction works with the appropriate color neighbors.

•In the global shutter mode, increased hot pixels can become visible in the lower image area with log exposure time, a high gain and disabled hot pixel correction.

•Both hot pixel corrections should be disabled if extremely fine structures are captured with a high-quality lenses.

•For the measurements of noise characteristics both hot pixel corrections should be disabled.

•The activation of the sensor-made hot pixel correction reduces the frame rate slightly. Here, the desired frame rate has to set after the activation or deactivation of the sensor-made hot pixel correction.

•Increased hot pixels can occur In the entire image border area.

Binning

•2x binning makes the image brighter by a factor of about two. It also reduces image noise.

•Binning does not result in a higher frame rate. Using binning allows higher pixel clock frequencies for USB uEye cameras with the USB 2.0 and GigE interface. To achieve the maximum frame rate, activate first the binning and then change the maximum pixel clock frequency.

•When using binning the frame is slightly shifted horizontally.

•Binning can only be enabled for both horizontal and vertical pixels. For this reason, the parameters of the is_SetBinning() function have to be passed together (IS_BINNING_2X_VERTICAL | IS_BINNING_2X_HORIZONTAL) to enable binning.

Scaling, AOI

•The digital scaling functions result in a higher possible frame rate. The maximum frame rate is increased approximately proportionally to the scaling factor. When using the scaling functions with USB 2.0 and GigE cameras, you can set higher pixel clock frequencies. To achieve the maximum frame rate, select first the scaling factor and then the maximum pixel clock frequency.

•For improved image quality without undersampling artifacts, the digital scaling feature permanently uses an anti-aliasing filter.

•On color sensors, the scaler works in consideration the color information.

•Reducing the horizontal resolution does not result in a higher frame rate.

•The available step widths for the position and size of image AOIs depend on the sensor. The values defining the position and size of an AOI have to be integer multiples of the allowed step widths. For detailed information on the AOI grid see the Camera data UI-124x/UI-324x/UI-524x chapter.

•The scaler remains active (but set to 1) if you have set an image size with the scaler.

Multi AOI

•When the Multi AOI function is enabled, no changes can be made to the image size settings (e.g. binning, subsampling, scaling).

•If sensor hotpixel correction and Multi AOI are enabled, the sensor displays a four pixel wide black line between the AOIs.

Sequence-AOI

•We advise to use the sequence AOI function in freerun mode only. If used in trigger mode incorrect image sequences may occur.

Fast line scan mode

•The exposure time is fixed to the readout time of one sensor line at fast line scan mode. Exposure time cannot be changed in this line scan mode.

•The time stamp is generated for the complete image for fast line scan mode.

•There is a time gap between two frames with the line scan information. This corresponds to the duration of 15 lines at a frame rate set to maximum.

•In the fast line scan mode color images are not possible as Bayer color sensors needs at least two neighboring lines for color calculating. Therefore, only monochrome models support the line scan mode.

Log mode

•The Log mode shows visible effect only for short exposure times (< 5 ms).

•In global shutter mode the Log mode can help to increase the shutter efficiency for extremely short exposure time (< 100 μs).

•To find the right operating point of the Log mode use the following procedure:

1.Set the Log mode gain to the minimum value.

2.Find the operating point via the Log mode value. The higher the value, the more bright image areas are damped and more details become visible.

3.Set the image as bright as possible via the Log mode gain. A typical value is 2 or 3 for monochrome sensors and 0 or 1 for NIR sensors.
The line view in the uEye Cockpit is very helpful for this.

•The master gain is disabled in Log mode.

•For color sensors set the RGB gain at the same value as before activating the Log mode. Once the Log mode is activated settings can no longer be changed.

•Different RGB gain values result in color errors as the transition from linear to logarithmic is different for each color.

•The image is brighter with activated binning and thus the log mode effect is not visible any more.

No-Anti blooming

•Activation: With exposure times over 10 ms and no use of gain or gain boost it can occur that bright image areas do not reach saturation and hence no white level. A visible, firm pattern is formed in bright image areas. For color sensors with enabled white balancing bright image areas get purple. In this case, disable the anti blooming mode (see Shutter: Log mode) or increase the master gain from 1x to 1.5x.

•The function should not be activated for short exposure times (< 10 ms). Depending on the shutter mode a "Black Sun" effect or overexposure occurs.

Micro lenses

•The sensor has non-removable micro lenses on each pixel. These micro lenses focus the incoming light for the subjacent smaller photodiode. This lens has a directive efficiency.

•To the corners of the active image area the micro lenses are slightly shifted to the photodiode. So the unavoidable non-vertical light incidence of C mount lenses is compensated. The shift is constant from the center to the corner and has a maximum of 12 degrees. When using a telecentric lens or parallel light incidence the shift must be considered as little shading effects may occur.

Hardware gamma

•Gamma is produced by the sensor at a value of 0.5.

•The results effectively shows 8 bit. using 10 or 12 bit has no effect on the image quality.

•The hardware sensor gamma curve is piecewise linear with three sections. This allows evaluating four times more details per pixel for lower gray level values and in 8 bit per pixel mode in dark image areas.

IDS line scan ("AOI merge mode")

•For color sensors, the IDS line scan can only be used with at least 2 lines.

•It is sensor related that 1 or 2 images must be dropped when switching to the IDS line scan.

GigE uEye LE

•In case of a reconnect (network connection is interrupted and reconnected while the camera is still powered on), the camera will continue to capture images. After reconnect, these images are counted as "transfer failed".