There's a simple scientific explanation for why flash photography often results in eyeshine — it's all about the construction of your dog's eye. (healthypets.mercola.com)
Later in the game Riddick receives his trademark eyeshine ability, which allows you to see in the darkness without the need of an often giveaway torchlight, it's a great ability to use in the gloom against oblivious enemies but the downside is that any contact with light is completely blinding. (consoleob.com)