Nikon D780 DSLR Camera (Body Only) - Manual (Page 804)

758 Troubleshooting
“Noise” (bright spots, randomly-spaced bright pixels, fog, or
lines) appears in photos:
• To reduce noise, adjust settings such as ISO sensitivity, shutter
speed, or Active D-Lighting.
• At high ISO sensitivities, noise may become more noticeable in long
exposures or in pictures recorded when the camera temperature is
elevated.