My vet hosted a animal fun day that featured a pet photographer. I brough Bandit in (he was my only dog at the time) and it was an adventure. He was young and very hyper. He was running around the little room smelling all the animals that had been there before him. I don't know how that photographer got him settled down and get this picture, but she did. I remember she had a lot of treats, and she'd give him one and for a split second after he got the treat his mouth would close and he's stop panting. I know she had to shoot many photos to get one without his tongue hanging out!

Here's the result:


Maybe animal fairs, Humane societies, or vets could give you some reccommendations?