I take it that this was a college or high school game? There's no official Minor League team in Baton Rouge. Based on the assumption that this isn't one of the teams that has a national TV profile, I'd say that you're pretty underexposed. I shoot a lot of baseball, including the low minors (low-A and rookie), and the lighting is uniformly pretty tough. It seems reasonable to expect that the colleges and especially high schools are no better and likely worse.
I can - usually - manage 1/500-1/800th, f/2.8, ISO 6400. I nearly always have f/2.8 glass, so I'm not often constrained. To shoot at 1/1000th, f/4 at ISO 4000, you're almost 3EV less than what I usually see. Apparently you dialed in +3 stops of exposure compensation, so your light levels are not so different - and yet the whites are grey, so still underexposed. Even the ball is pretty grey. Given that you're underexposed, I'm not very surprised that you see noise in the NEF file. I'm shooting a D3 and it's certainly the case that ISO 3200 files must be processed to avoid overt noise - these sensors are a lot better than ones in the past, but they aren't magic. Noise is still present, especially if you're not absolutely smack on the exposure, or ideally overexposed. (Overexposure is pretty darn hard with white uniforms, since an overexposure of almost any magnitude will blow out the whites.)
If this is a high school game, I'd bet that the lights are a good stop or even a stop and a half less than the Minors. If that's the case, I'm surprised that you see as little noise as we have here. One little league field I've been to is a full two stops down from MiLB - that's dark. I can't imagine how the hitters ever hit anything!
(For reference, my experience has been that the minors, even the modern AAA parks, are almost three stops down from the Majors. It's not so hard to shoot at f/8 in the MLB parks, even at night.)
_____ Brian... a bicoastal Nikonian and Team Member
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