Porcupine in winter

Many photographers think when shooting on snow, you should always overexpose from what the meter says by about 1 1/3 f/stops. They reason that this compensates for underexposure that occurs because of the meter's reaction to the whiteness. That is true in some instances, but not all. This shot of a porcupine in winter is an exception to the rule. The center of the frame isn't white at all, and the meter takes more of its information from the center of the composition. For this shot, I didn't use any exposure compensation at all even though I was shooting in a snowy environment. The settings were 1/800, f/7.1, and 400 ISO, and I used a 500mm lens plus a 1.4x teleconverter for 700mm of focal length. I was concerned about losing detail in the dark face, and in post-processing I lightened the shadows a bit to reveal detail in the facial features.