To start making a HDR picture, you’ll usually need more than one photograph, especially when the scene involves high contrasts of light and dark. Once you’ve composed and shot your first picture, take a look at your camera’s histogram (samples shown above). If the graph shows the image is overexposed (like the graph show at the top), try increasing your shutter speed for the next photograph. If it’s underexposed (like the graph at bottom), reduce the speed.
The object is to get a series of photos where eventually you will see both ends of the graph: the points where the histogram trails off into nothing. This process is often called shutter speed “bracketing.” Keep all your photos for the following step, which we will cover next in this series.