Your Linkedin profile need a proper portrait photo to secure a professionel first impression
Your Linkedin profile need to be up-to-data and tailored towards "opening doors" for new opportunities. This also include your profile photo. The visual first impression is an extremely important element when your Linkedin profile are being viewed.
If a portrait has to function well on platforms like Linkedin, the face has to fill the major part of the frame. I like to work with natural light and a fill flash, which enables me to work fast and still create some interesting shadows and a catch light. The back drop can be neutral or "busy" but need to be out of focus so it helps frame the face.