Here are the SNR graphs from yesterday, but for the D800E instead of the D4. There is even less reason to increase the ISO to improve the SNR of midtone and brighter values than there is on the D4.
Note how low the statistical variation is compared to the D4. Why? I don’t know.
Should you just leave the ISO setting of your D4 and D800 at 100 for everything? I need to look at what goes on in the shadows to answer that question. Stay tuned.