It will most likely be the same issue as with the D700, as the D800 body looks very similar in size if not identical. I have the D700 and 24PCE, and there are certain extreme positions where the pop-up flash housing gets in the way. I tried this out back when I got the lens, but I don't remember what those restrictions were - for a good reason: I never encountered them in real life shooting. The lens works just fine on my camera, and I;m sure it will on the D800, too. Legally Nikon won't be able to claim it is compatible, because then somebody will point out that scenario and complain.