Do I understand it correctly that a networkable 4 channel dvr can take the video inputs from four separate cameras and continuous record all four at once. Does anyone have one of these surveillance systems? Does each one of the surveillance cameras get recorded on a separate track or is it a split screen type of thing with all four security cameras sharing the screen on a single recording? I think the latter might make the images a little too small for good detail like face recognition in the event that there is any trouble. If you know how this works, let me know, thanks.