You don’t need any special memory cards to make use of the D850’s amazing resolution, but if you want to exploit its speed as well you may need to upgrade your kit. Achieving the 7/9 frames per second is not the problem – it’s how long you can sustain this speed which is the issue.
We couldn’t source Nikon’s recommended 64GB 440MB/s Sony QXD card, so we tried a 299MB/s Sony UHS-II SD card and that started to slow down after 30 Raw shots at 7fps.
We also tried a Lexar Professional 440MB/s XQD card and that did make a big difference, but it also highlighted a very important point – the D850’s buffer capacities apply specifically to the in-camera 7fps shooting – in our tests, we did indeed get within a whisker of Nikon’s claimed figures.
However, when you’re shooting at 9fps, the buffer fills much faster and this caused a big drop in buffer capacity. At 9fps, our D850 captured just 22 uncompressed or lossless compressed 14-bit Raw files, and 30 compressed 14-bit Raws. It looks like you can have shooting speed or Raw buffer capacity, but not both at the same time.