Getting a photo of your dog that will be a great reference for a portrait painting is surprisingly easy if you follow a few simple guidelines. What actually works best is to start with photos that don't work. Photos that look down at your dog. While we're used to looking down at our dogs, a portrait that is downward looking rarely looks good and often makes the dog look subservient and puny; not the object of getting its portrait painted! Photos with flashed eyes. While I can work around such photos sometimes, I can't really convincingly supply visual information that's not there in the reference. We artists are only as good as our reference photos: "garbage in, garbage out". Photos that are very dark or backlit so that the dog's face is in shadow.