The Nikon D850 has two memory card slots. In one, you can use either an XQD or CFexpress B card. In the other, you can use an SD card.
You have some control over how the memory cards are used depending on how you want to prioritize maximum storage space, speed, and workflow convenience. You can treat them as sequential memory so that when one card fills up it automatically switches over to the next one. You can copy to both simultaneously to create a mirrored backup version. Or you can send image files to one and video files to another.
Unlike some other cameras, where all the memory card management is handled in the same area of the menu system, there are actually two places on the Nikon D850’s menu system where you can control where and how files are saved to the card.
Saving Photos to the Memory Cards
In the photos section (the green camera icon), got to `Primary slot selection’.
There you can choose either XQD or SD. (Note: the menu system will refer to “XQD” even if you’re using a CFexpress B card.)
You can then go to the next menu item, ‘Secondary slot function’.
That will give you some options to manage how the two cards work together:
- Overflow – This uses the card in sequence. Once the first fills up, it automatically moves onto the next one.
- Backup – This saves a duplicate version on each card. Worth noting is that it will take a little longer and use a tiny amount more battery power to do this.
- RAW primary – JPEG secondary – This option is a little odd in how it behaves. If you have the image quality (`Photo Shooting Menu > Image Quality’) set to one of the NEF (RAW) + JPEG options, it saves the RAW file to whichever card you’ve nominated as the primary card and the JPEG to the secondary card. Which is straightforward enough. But if you have just RAW set for the image quality, it will save a NEF file to each card. And you get the same kind of behavior if you have the image quality set to only a JPG: it will save a JPG version on each card. So it overlaps under some circumstances with the Backup option above but is subtly different.
Saving Videos to the Memory Cards
The Nikon D850 leans heavily into stills photography, and that’s where its priorities clearly are. But it does have some solid video capabilities.
And if you’re looking to control how video is saved to the memory cards, you actually have to go to a different part of the menu system. You find these under the Movie Shooting Menu (which is the yellow movie camera icon): `Movie Shooting Menu > Destination’.
You don’t have the same kind of options there. You can only choose which card the video files are saved to.1
Things Worth Knowing
You can also copy from one memory card to another in the D850. I have a post on how to do that here.
And there’s a shortcut to format memory cards in the D850. You can find more information on that here.
- Well, to be more accurate, you can also choose the three-letter file naming prefix with the menu item immediately above it. ↩