On both of these bodies you have to set the image type or types you want recorded.
Go to Photo Shooting Menu and select Image Quality. For RAW or NEF, select NEF. For both NEF and JPEG select NEF/JPEG.
You may have to reset or change settings in other related categories: NEF Recording and Image Size.
In both of the manuals for each camera read the info Photo Shooting Menu. In D850 manual it starts on page 250.
If you do not have the manuals you can download them from NIKONUSA. I also download a separate Menu Guide manual.
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