What is it that's being exposed? How is it exposed? Good questions if you are wondering what exposure means for you and your photography.
Above: In the collage above the big picture on the bottom was created by combining three photographs to create one picture. This is done through bracketing and it is how you can produce HDR (high dynamic range) pictures. I used Photomatix, a software designed to layer pictures together, to create the final picture.
Exposure comes from the root word expose. To expose something or someone is to subject them to any number of things, ideas or actions. In digital photography, the photographer is subjecting the camera’s sensor to light when the camera’s shutter is opened. The result of this light being exposed onto the camera sensor is a photograph (also called an exposure).
There are two opportunities for a photographer to make choices. One is composition. This involves where you are as a photographer in relation to your subject and other things in your picture.
The other area where you have a choice is exposure. You can choose to shoot in your camera’s auto-mode or you can shoot manually. In auto-mode the camera is going to make the settings for you. In manual mode, you are in control of your ISO, aperture and shutter speed.
If the black colors in your picture seem to dominate or appear too big and strong you may have underexposed your picture. If you have areas that are blown out and white you may have overexposed your picture.
If you are not sure what settings to use, shoot in auto-mode. Most likely it will give you an even exposure and will likely be all you need to “get the shot”. But if you want your picture to stand out, if you want it to have more meaning and power shoot in manual mode. This will let you pick and choose how light is processed and eventually exposed onto your camera sensor. And quite frankly this is one of the most fun and challenging parts of photography. So, why would you just let your camera make all the decisions for you?