I was out photographing birds and ducks so I had my 500mm lens on my camera. I saw a man playing fetch with his dog so I asked if I could get some shots for my website. If I were to scheduled a pet photo shoot, I never would have considered using this lens for a shoot...probably wouldn't have gone over 200mm. With that said, I am really glad I had no other option and will definitely consider using this lens again for a pet shoot.