Getting a good shot of a dog can be alot of work; and it can be a super capture in the spur of a moment. But typically when I'm doing a shoot there is alot of waiting it out. Having a dog relaxed is probably the most important part of a great shoot. That is why up until now I have not worked in a studio.
I've had my own dogs shot in a studio many years ago to help out a photographer for her advertising. I brought all three dogs and all three dogs were not themselves. This left me with a definite experience to fall back on. They were antsy, out of sorts and basically not themselves so getting a facial expression that I see on a regular basis was not going to happen.
Of course now that I am a dog photographer; being a dog trainer specializing in behavior modification helps me greatly. I am always looking for expression; whether it be relaxed, goofy or I'm getting the look. I talk to the dogs occassionally but I mostly use my body language.
Many dogs are uncomfortable being photographed; not the way that humans are uncomfortable but by the fact that there is a strange cyclopse(sp?) staring at them. Lately I've had quite a few dogs that are so uncomfortable that each time I point the camera at them; they become unglued. So again I sit; chill and perhaps change my lense. If at all possible, unless I'm going for a scenic landscape shot I like to use my mid-big lense. This allows me to move away from the dog; out of their space.
But, then there are the dogs that do best with me in their space and face. Some dogs give me the best and funniest expressions when I'm right up there; close and personal. When I'm on a role and getting some great shots I will often want to move a little closer; this can be tricky. I will immediately assume a sideways approach, looking off into the distance so the dog thinks I'm not focused (pardon the pun) on them. Then I quick snap the shot.
You cannot be a dog photographer in my mind if you don't love dogs; love spending your whole day with them and have the utmost of respect for their feelings. You can't get a good shot if the dog is not comfortable; plain and simple.