Seeing the way a camera sees, Part 2

The camera sees less than half of what you can see

Where the camera has the human eye beat as far as the detail it can “notice,” the human eye humiliates the camera when it comes to the amount of light it can detect.

If the human eye were a camera, it would be able to adjust from an ISO range of 1 to 800. That gives us the ability to distinguish about 10,000 levels of light from total black to total white (about 10 and a half stops). The camera (or rather, film or a digital sensor) can at best record about 5 stops of light at any given ISO rating.

So, on average, your camera will not even be able to record half of the tonal range of what you see in a given scene. This will explain why what you could clearly see in the shadows of a brightly lit scene come out as a totally black blob in your photo. Or why those details in the snow are lost in a glare of white on your computer screen or print.

To give yourself an idea what your camera will record in a given scene, squint your eyes until they are a little less than halfway open. If you don't like what you see, you probably won't like a photograph taken of it either.

The best way to help the camera out is to avoid as much as possible taking pictures in very contrasty lighting, such as that found at midday. The light found a half-hour either side of sunrise and sunset (referred to by photographers as the “golden hours”) is less intense and more ideally suited to the limitations of the camera.

If you find yourself having to shoot in bright, contrasty light, the use of a flash unit to “fill in” shadow areas can improve your results.