Dewey. The answer to your questions depends on how accurate your inspection system needs to be. When you trigger all of your 1411s at the same time, they will all acquire the next valid image from their camera. So with cameras that acquire at 30 frames per second, your acquisition could be off by as much as 33 milliseconds, since that is the time between frames. If you can tolerate a maximum delay of 33 milliseconds, then there is no need for genlocking.
Kyle V