Understanding Histograms

1. A histogram is a tool used in photography to show a graph of the tonal range in a picture.  If there are high peaks on the graph at any point, it means that there are more pixels of that tone.

2. When a histogram is skewed to the right, it means it has a mass of dark/black pixels, whereas if a histogram is skewed to the left, it has a mass of light/white pixels.

3. There is no such thing as a perfect histogram.  The histogram varies based on what you are shooting.  If you take a photo of something with a white background, the histogram would look completely different then if you took a photo with a black background.  There is nothing wrong with either of those photos, but a general histogram should have balanced tones.

Ex:

4. Histograms are good for photographers because they can show them the spectrum of pixels in their photos.  They can also show the photographer if their picture is underexposed/overexposed.  Histograms give them more details on their photos and give them the effects they want.