Nikon D500 Professional Setting Manual page 9

The Movie Crop
The movie crop varies with frame size and, at frame sizes
of 1920 × 1080 and 1280 × 720, the option selected for
Choose image area in the movie shooting menu.
1920 × 1080 or 1920 × 1080 or 3840 × 2160
1280 × 720, DX 1280 × 720, (4K UHD)
image area 1.3× image area
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