There's a thing in the pet rescue community called "The Black Dog Problem" or "Black Dog Syndrome". It seems that it is more difficult to place black dogs with new "parents".
Part of the problem is that it's hard to photograph a black dog. If you take a picture of a black dog in normal daylight, they just look like a black blob. If you take a picture of them indoors with a flash, all you are likely to see is their eyes and teeth. If you don't have a good pic of the dog, it's harder to place them with a family. Read more here http://www.nbcnews.com/id/23472518/ns/health-pet_health/t/black-pups-face-doggie-discrimination/#.WJKeyfkrJPY and here http://www.blackpearldogs.com/
My little buddy Ellie is a black lab. I've learned a lot about photographing black dogs because of her. I've found that a black dog photographs more beautifully under the right conditions than any other color of dog.
The camera sees differently from the human eye. When you look at something, your eye adapts to the amount of light that's available from one part of the scene to the other. The camera can't do that. It takes the scene as a whole and does the best it can. So if a camera is photographing say a black dog in bright sunshine, it adapts to the bright scene and the black dog is underexposed.
The key is to photograph the black dog against a black or dark background. Then, the camera only has to deal with a limited range of light. Check out these pics of Ellie to see what I'm talking about.
Click on picture below to cycle through some of my favorite pics of Ellie:
