When sliding through the image in one direction, some scans show a “flickering” in the display of the 2D slices. This is common in FIB-SEM scans and these images require a Flickering Correction.

First choose the Direction, along which the flickering occurs: X, Y, or Z.

The Correction Method provides the two options Multiplicative and Additive. The choice of method depends on the processing applied by the image acquisition device. The scanned image data usually provides information about whether the acquisition device uses linear or logarithmic image processing. If the processing is linear, use the Multiplicative correction method. If the processing is logarithmic, use the Additive correction method.

Click Apply to correct the flickering according to the given settings.

The dataset below is a FIB-SEM of a cathode provided by Zeiss. A flickering can be observed along the Z-axis. Slices 56 and 57 are shown as an example. Slice 56 is slightly darker than slice 57 and the histogram in Z-direction also shows high variations. After applying the Flickering Correction in Z-direction, the slices have the same brightness and the variations in the histogram are much smaller.

To analyze a scan on flickering, either scroll manually through the slices in the Image Processing dialog or create a video slicing through the structure. For this, in the main GeoDict GUI select File → Save Video as and under the 2D tab find the Back To Front (all slices) and the Front To Back (all slices) presets. For more detailed information about creating videos with GeoDict, refer to the Create Videos user guide.