When we do not use the common resolution but use other values, let's say 384x136, I find the FPS=40.86 while there is a max FPS =50.I get confused about why there are two FPS? Does that mean with a specific resolution, there are two different FPS for us to choose? The default FPS is the one 40 and we can get FPS=50 with a smoother video by choosing the max value? How do I know which FPS is the one for current setting?