understanding histograms
If your digital camera
has the option to display a histogram, it can be a very useful tool
in getting a properly exposed shot. Here is a very simple guide
to their use. |
|
| Here the distribution of pixels is biased at the shadow end of the histogram, with a very small amount of pixels in the highlight areas. This will result in a loss of detail in the shadow areas and that detail may never be subsequently retrieved. | 
Underexposed |
| In this histogram shows a leaning towards the highlight end. This indicates that the highlights are being blown out and subtle details in those areas will be permanently lost. |  Overexposed |
| This histogram is stunted with all the pixels centred on the mid-range and no pixels in either the shadow or highlight areas. The resulting image will appear flat or hazy. |  Low Contrast |
| A histogram like this where both the shadows and highlights have been truncated indicates that the camera is failing to record the full range of tones and that the contrast is too high. | 
High Contrast |
| In a well exposed shot the histogram will look similar to this - with both shadows and highlights recorded well. There are few pixels at the extremes and a slope at each end showing the gradual build up of tones. |  Fairly "normal" exposure |
