In fluid dynamics some quick flow visualisation can often reveal a lot about the flow. Here we have dye injected into the upstream flow of the water channel. You can see two parallel streams on the very left hand edge of the photo. After passing the normal flat plate, the shear layer vortices are very evident. In the green dye you can see 3 or 4 shear layer vortices before the von Karman vortex forms roughly 3 chords downstream. The pink dye is forming the close von Karman vortex. This shedding process is symmetric and regular.