Motion direction perception
The difference of the probe objects (convex, concave hemispheres or flat circle) in veritcal motion path does not affect the motion direction perception.
The moving objects are convex hemispheres.
The probes are "Flat".
The probes are "Convex".
The probes are "Concave".
Motion smoothness perception
The moving objects are "Convex"
The smoother motion would be perceived in the case that "Flat" probe objects are presented in vertical motion path relative to "Concave" probe objects.
"Flat" vs "Convex".
"Flat" vs "Concave".
"Convex" vs "Concave".
The moving objects are "Concave"
However, the difference of the probe objects in the smootheness perception diminished when the moving objects are "Concave".
"Flat" vs "Convex".
"Flat" vs "Concave".
"Convex" vs "Concave".