A key skill for any pet photographer is understanding canine body language and recognizing signs of stress. Some are more apparent like a tucked tail or flat ears, but others can be more subtle and an uninitiated photographer might think it's cute to capture a dog lifting a front paw, but as a Certified Professional Dog Trainer as well as a Certified Professional Photographer (CPP), I know this is a sign of stress and I would not make that image and would stop the session to help make the dog more comfortable.
I've been training at Camp Bow Wow in Coppell, Texas for nine years now. The process to earn my training certification was more arduous than that for my photography certification (ask any CPP and they'll tell you it was hard!), and it should be, you're working with another living being.
I'm a believer in science-based training methods that encourages a dog to think and problem solve while learning from the choices they make. There's no punishment for wrong answers. The worst that can happen is, well, nothing. No treat, no pet, no toy. That's it The dog learns as much from getting it wrong as they do from getting it right because they learn what doesn’t work. This is also known as positive reinforcement training.
Dogs are master manipulators so I use that inherent nature and strategically set up the environment in such a way that it's easy for the dog to do the behavior I want and then I add reinforcement to it. Every dog will revisit behaviors which have paid him well in the past. Whey do dogs put their butt on the floor when you make the sound "sit"? Because you give them forty seven treats in a row the day you trained it. Why do dogs counter surf? Because they scored that delicious hunk of stew beef that time.
Positive reinforcement training should be fun for the dog, but even with no "wrong answers", some dogs may not be totally comfortable with a new person actively engaging with them, or with a particular behavior (i.e. tiny dogs are notorious for being difficult to train "lay down" in a group class environment; it can be a vulnerable position for them and with so much going on around them, they'll take a hard pass on that), so it's important to be able to recognize that and accommodate accordingly. As a dog training professional, one of the professional organizations I belong to is the Pet Professional Guild whose motto is "No pain. No force. No Fear." I extend this to my pet photography as well. We are going to create beautiful images of your dog while keeping them comfortable. Full stop.
There are some very comment displays of stress for dogs that everyone recognizes, but here are three that you may not have know about.
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