Real World Dynamic Range

Let's get something out of the way right up top: the Nikon D810's ace card is its massive dynamic range at ISO 64. Actually, not just dynamic range, but stunning image crispness and cleanliness, thanks to its ability to capture more light at ISO 64 than any other full-frame out there. In fact, the 0.7 EV extra light the D810 can eat up before clipping the same tones a similar camera might clip at ISO 100 essentially allow it to catch up to medium format cameras like the Pentax 645Z. Think of it like this: the extra light the 645Z can capture - due its ~66% greater sensor surface area - the D810 can capture, thanks to its ability to accept nearly 60% more light at ISO 64 than most other full-frame cameras at ISO 100.

Let's repeat that: the D810 catches up to the medium format Pentax 645Z's dynamic range.* Don't believe us? We'll show you.

We shot four cameras side-by-side, bracketing exposures as quickly as possible. We then used RawDigger to select the images that were 1/3EV short of having clipped highlights, a method that is not only a staple of ETTR (or expose-to-the-right), but also the only sensible way to compare dynamic range on a common, saturation-based, basis. The D810 image was shot several minutes after the others, so don't read too much into the exposure settings used.**

These images, which were severely underexposed in all areas but the sky, were then processed to have approximately the same brightness and white balance. As you can see, the ISO 64 setting allows the D810 to capture around 0.7EV extra light, which improves the signal-to-noise ratio across the whole image, a difference that is visible from the shadows all the way up to what are rendered here as mid-tones. In fact this 0.7EV extra capacity for light allows the D810 to produce an image that's very similar to that of the 645Z, since 0.7EV is very close to how much benefit the Pentax's larger sensor would be expected to give, all other things being equal.

Look at the underside of the trim around the lighthouse, or move the crop around to inspect similar rocks in the foreground: the noise levels in the D810 shot are closer to the 645Z than the D800, indicating that ISO 64 on the D810 does offer an advantage over the ISO 100 performance of the otherwise similar sensor in the D800.

Let's take a closer look at a couple more scenes to see how Sony and Canon flagships compete:

D810 beats the Sony a7R II

We all knew that Sony sensors are great, but now we know: not all Sony sensors are created equal. The D810's tweaked Sony sensor at ISO 64 setting allows it to tolerate 0.7EV more light than Sony's own a7R II (1/8s vs 1/13s shutter speeds, at F5.6, respectively) before clipping the same tones in the sky. The extra light means the D810 can render shadows and midtones more cleanly, since more light means less relative shot noise, which means a higher signal-to-noise ratio. So, although the two cameras will perform very similarly at ISO 100, the D810's ISO 64 setting gives it an edge in circumstances where you can keep the shutter open 0.7EV longer, or shoot with a 0.7EV brighter aperture.

D810 crushes the 5DS R

As you've probably come to expect by now, ISO 64 along with a low noise floor allows the D810 to positively crush the Canon EOS 5DS R. In this instance, it took another whole stop of light, compared to the Canon, for the highlights to saturate the sensor, making an already dominant performance look even better. Even if you don't intend to shoot such high dynamic range scenes, the Nikon D810's shadow regions are likely to be cleaner on any occasion you lift tones or selectively increase contrast.

The dynamic range of the D810 allows for incredible latitude in processing. I exposed this shot for one lightning burst, which resulted in largely black image. Despite a 4 EV push, I got a usable image of the entire beach, and sky. It all starts to make sense when you consider that an ISO 64 file pushed 4 EV has similar noise levels to an ISO 1000 shot for most tones, because of the camera's ISO-invariant nature. ISO 1000 on full-frame is certainly considered 'usable' by many. Photo: Rishi Sanyal

And it's not just about dynamic range...

ISO 64 is not just about shadow recover-ability and dynamic range. You can always give the camera an extra 0.7EV, even in normal scenes. So where you might shoot a daylight portrait at ISO 100, 1/800s, F2 on a 5DS, you might shoot that same portrait at ISO 64, 1/500s, F2 on a D810. That extra light means higher signal:noise ratio for all your tones, which translates to more flexibility in post-processing. Take a look at this 5DS R portrait at 100%; I didn't drastically lift shadows for this shot, since I let the sky blow in my exposure. However, the contrast, sharpening, and saturation adjustments I made led to visible noise in the green grass or on our model's jacket. In fact, all such adjustments carry with them some risk of making underlying shot noise, noise inherent in light itself, more visible.

So what do you do about this? You shoot with a larger sensor cameras that capture more light - it's why pros shoot medium format - or you shoot ISO 64 on the D810, which has largely the same effect.

* Note that the D810 really only catches up to the 645Z at base ISO, when you can give the camera that extra light because you're on a tripod or it's bright outside. At higher ISOs, when you're light-limited, larger sensors will almost always perform better, all else equal.

** This does not affect the dynamic range of the scene appreciably (we measured it from the Raw files). We had 3 operators controlling 4 different cameras, so the exposure settings chosen at any moment for any camera weren't synchronized. It just so happened that the perfectly ETTR'd shot for the D810 was from a set shot a few minutes apart from the other three.