For what it’s worth, when I look at this picture, I definitely take the scene as "this is real." It’s very convincing. But I do see a couple of fundamental lighting/exposure problems, which I would describe equally for a CG image or a photograph:
[li] The eye is always drawn, like a magnet, to the brightest and/or the most contrasty part of the picture. Which in your case is, unfortunately, the lights at the top of the frame. Zi-i-i-ip! My eye just shot “up and out of” the picture. Whups. (My eye also pauses at the shape below the horse’s neck, then goes straight up the “pipe” to hit the poor horse. Whack! [*] The body of the horse, despite “all that light,” is murky and underexposed. The side of the horse actually drops all the way to “featureless black.” Serious boner. The ghost of Ansel Adams would rise up and lecture you. But it’s also rather implausible: the horse is directly below “all those lights” and certainly would receive sufficient illumination. [/ul]
Also… if I were shooting this scene with my trusty 4x5 camera, I would probably have a couple of soft-cloth reflectors casting light into the shadow areas just to bring the tonal range back within the parameters of the film I’m using. I’d be all over the carousel with my incident-light meter, muttering to myself, “This will be zone-5, this needs to be no less than zone-3, and this highlight no more than zone-7…” And if I can’t compress it quite that far in the field, I’m going to be making notes for the darkroom.
And then, all things considered, I just might recompose the shot. For example, what if you panned the camera to the left so that you cropped-away the very bright (burned out) light patch at two o’clock? (Put your right hand over the image and have a looky.) Isn’t that a much better shot?