The Importance Of Exposure
Click to explore how changes in exposure make pictures lighter or darker.
One of the things that makes an Ansel Adams print so stunning was his ability to hold details in both the brightest and darkest parts of a scene. To do this with film he developed the Zone System that guided him in adjusting exposure and development times for the best results. Today the adjustments are made with a photoediting program.
Knowing how to control exposure is one of the most important aspects of photography. When a scene has both very light and very dark areas, getting the perfect exposure is a lot like parking a large car in a small garage—there isn't a great deal of room for error. The goal is to hold details in both the darkest and lightest areas so pure white is used only for spectral highlights such as reflections and pure black is used only for those few areas of the scene that are black with no details.
In this scene there are details in all of the whites that give them texture and form. The small white square has been added to give you
a reference to what pure white would look like.
In this scene there are details in the darkest shadows. The small black square has been added to give you a reference to what pure black would look like.