Camera settings instead of RAW I have come across several articles in which the camera settings for shooting video are explained. If the camera does not provide RAW footage it is recommended to set Contrast, Brightness and Saturation as low as possible, and also change the midtones curve adjusting lowlights to high and highlights to low, in order to get an image as flat as possible.
This way it is claimed that the footage can be easily post-produced.
I wonder if that is a valid way, or if it is better to adjust as desired the image on camera.
Any thoughts would be appreciated.
It highly depends on your Bit-depth and scene and post-production. If you're trying to maximize for dynamic range and avoid clipping highlights for example, you should reduce contrast as much as possible (and also expose for the highlights). However, by doing that you might lose details in the midtones (separation of colors and luma), which might lead to banding issues after post-processing the footage (adding contrast and saturation), especially if you are recording 8-Bit per channel, which most consumer cameras do.
From my personal experience if you are recording 8-Bit you are probably better off getting your exposure as finished as possible in the camera and only do little post-processing to avoid banding or similar issue. If you're recording 10-Bit, you have way more information to play with and could use LOG profiles (which are another way of reducing contrast and saturation) instead.