There are 2 Points to look for if you are using the photographic exposure control: 1.It heavily depends on the sizes of the scene 2.You have to use the MR Lights for it to work correct(not 100% sure about this, but i think it was something like that)
edit ignore me don't want the gaming blogs to put 2 and 2 together and make 5. It was a batman related side-project im working on, independantly, but it's probably best I wait lest people get the wrong end of a metaphorical STICK.
It's all Photoshop. The octopus itself is in a file that's 5000x5000(16 2/3"x16 2/3") at 300 DPI. The canvas it's on at the moment in that screenshot is 17x11 so I actually have a good bit of resolution. I'm good up to ~24"x24" with this setup.