What does Auto FPS do when recording iPhone video? How does Auto FPS increase video brightness?
The iPhone camera can automatically adjust FPS or frames per second when recording video. Auto FPS helps to improve video quality in low light situations. In particular, when recording at 60 FPS this rapid shutter speed can greatly reduce the amount of light available to the image sensor. By slowing the shutter speed to 30 or 24 FPS the iPhone gathers more light, which brightens the video.
Auto FPS is a setting that drops the frame rate when needed to improve recording of low light scenes. On the iPhone 12 and later, navigate to Settings -> Camera -> Record Video -> Auto FPS -> Auto 30 & 60 fps. When enabled, the iPhone adjusts the frame rate between 60 and 24 FPS depending on the available light.On older iPhones, toggle Settings -> Camera -> Auto Low Light FPS -> ON (green switch).