In the blob finder, there are two different threshold modes: automatic and manual. In automatic mode, the blob finder will seek “light on dark” or “dark on light” blobs that fit within the area thresholds. This can be good enough when the part is very simple and has clearly defined blobs with little noise in the image. In these cases, the heat map functionality is not needed.
However, in cases where there is more noise in the video image, as shown below, the automatic mode may not detect the desired blobs. It is essential then, to select manual mode and narrow down manual threshold values so that the upper and lower thresholds fit into a window of acceptable values. The heat map helps with this by giving a visual representation of what blobs will be detected by shifting the live video image to a pseudo-color image that illustrates the manually chosen threshold values. When the heat map is active, the video window will illuminate the pixels that fall within the range selected in the manual threshold parameters.
When inclusive polarity is selected, pixels within the minimum and maximum thresholds will be illuminated. The pixels will light up according to pixel intensity on a color gradient moving from violet to red as shown below.
