Have you met my dog Bella yet? She LOVES to sun bathe and I can get the happiest smiles out of her when she is. I recently have been shooting in Black and White RAW using the Monochrome setting , on my Canon 5D mkiii It has taught me so much with highlights and shadows! I show you this image So you can see how wonderful the black and white contrast on my dog helps in showing the detail. Usually I would either get BLOWN out Whites or WAY DARK Shadows. When you shoot in Black and White Raw, You are able to SEE the exposure better, at least for me. I have found that when I upload all my images (they upload in color btw) They all look AMAZING to say the least and very little processing is needed later. I just barley adjusted the fill, contrast, and sharpened these images.

Try shooting in Monochrome (practice first) and see if it helps you on getting a better exposed image!