How to Use the Aperture to Control Depth of Field in Photography

Aperture size controls the amount of light that that enters the camera and performs a critical function for focus. The smaller the aperture, the background and foreground gain sharpness. The zone of sharpness is depth of field. Select an appropriate aperture setting to emphasize details in your photograph. Changing aperture affects depth of field, even when all other conditions are identical.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• Camera

1. 

   Determine depth of field. A camera that has a ground glass focusing system will display objects with the same sharpness as they will appear in a finished print.

2. 

   Look for bracket marks on your lens. Some lenses have depth of field scales on the side of the lens. When you focus your lens, you can look at the bracketed numbers on the lens to check what portion of the final picture will be in and out of focus.

3. 

   Open the aperture to its widest setting, f/2, in order to create a shallow depth of field. Foreground and background will have a soft focus. The middle region and objects, will have a sharp focus.

4. 

   Adjust aperture settings to the smallest opening, f/16. This setting radically changes the picture from a wide aperture setting. With the camera focused on the same point as with a wide opening, depth of field increases so that middle, background and foreground, sharpen in focus.

Resources

• Depth of Field Explained
• Using Depth of Field and Aperture
• Back to Basics: Aperture