For group photos, a wide-angle lens is preferred as it allows you to accommodate more people in the frame. However, be cautious with ultra-wide angle lenses for Canon as they can cause distortion at the edges of the image. A standard zoom lens is also a good choice as it covers a range of focal lengths, allowing you to zoom in on subjects without changing the lens. Opting for a lens with a large maximum aperture will provide a shallow depth of field and create beautiful background blur, especially in low light conditions.