A photo op refers to a professional photo session run by a photography company within a convention. The session typically involves a professional photographer, professional lighting, and a high-quality camera, resulting in a glossy print and a downloadable digital version of the photo. On the other hand, a selfie is a photo taken on your cellphone, typically at the celebrity's autograph table. The quality of a selfie can vary based on your phone's camera quality and the lighting conditions, and unlike a photo op, it may not provide a physical print.