>>1350280The bones in your hand aren't fixed when you're rotating your hand around.
So the base of your ring finger is shifting slightly up and down.
When I have my hand like in your second pic, but rotated 90 degrees CCW (fingers pointing up), my ring finger appears to be the same length as my index.
When I rotate it back 90 degrees CW (same as in your pic) my ring finger appears to be nearly as long my middle finger.
