The best focal length for taking a family photo is 35mm, and faces below 35mm are easy to deform. Usually, a family photo with about 10 people is no problem. To take a good family photo, it is recommended to use a tripod. When the aperture is set to f8 or f 1 1, and the iso is set to 100, the shutter will adjust itself according to the light. When shooting, people stand in formation, the camera constructs a picture on a tripod, and you can shoot with time delay or ask someone to help you press the shutter.