The Nikon D810 replaces both the D800 and D800E, and although it might appear to boast few improvements over the older models, the changes that Nikon has made are significant. There's no OLPF to get in the way of resolution, and as well as a lower base and higher maximum ISO sensitivity, the D810 is 25% faster than its forebears, offers a slightly improved AF system and 1080/60p video with built-in stereo recording. It also features an electronic first-curtain shutter option and a redesigned mirror mechanism intended to reduce vibration.