2. Get the exposure right. Because of the reflection caused by fog and mist, your meter will think there is more light than is available. To compensate for this, you have to increase the exposure above your camera's recommendation. If you have an exposure compensation dial, add an extra stop with +1. With manual and film cameras, you can do the same thing by setting the ISO for half of the actual film that you are using. If you are using 400 speed film, override the ISO to 200.