It depends on just how late you are staying in the park past closing. Within the first 45 minutes or so, there are still plenty of people lingering, getting out of food service places, coming off rides, etc, who start towards the exits, that you could still likely get away with heading slightly off the entrance direction - if a CM asks, you can always mention that you were heading to meet family at another park section and heading out together. Unless you were the very last person there, you probably wouldn't even be hassled. I will usually stick around a good hour or so after closing - and even when I think surely I must be one of the last people there, and it starts getting really abandoned looking, I start walking along and end up running into other people. Once you pick your farthest spot you can get away with, start taking all your night photos in a clearly determined way, that shows you appreciate the need to clear the park and you don't intend to be a problem...I set up the tripod, quickly start my exposure, and as soon as the shutter closes, I pick up the tripod and walk a few dozen feet in the direction of the exit...then maybe stop for another shot, and so on. That way, even if CMs are within view of you, or watching you, they see that you are working your way out, and as long as there are still others somewhere in the park, they aren't generally going to pay you any mind. I'm not too keen on being the very last one, where the CMs are almost pushing you out of the park...about an hour or so is reasonable, because there are generally still a few of the last riders on rides and last diners who had the very last dining reservations, who are just getting out, and you're still not the last one there...yet the park is empty enough you can set up your tripod almost anywhere and take some nice long exposures without worrying about crowds tripping over your tripod legs and walking through your shot.