Select a Specific Topic or Scroll Down to View Knowing the depth-of-field range for a particular situation is critical to the success of a photograph. To provide this information, Explore Photography has developed several Depth-of-Field Charts. There are separate Depth-of-Field Charts for each of five commonly used lens focal lengths (28mm, 35mm, 50mm, 70mm, and 80mm). Each chart lists the depth-of-field range for each combination of aperture setting and subject distance. The aperture settings listed are: f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, and f/32. The subject distances listed are: 2, 3, 4, 5, 6, 8, 10, 15, 20, and 30 feet on one side, 0.75, 1, 1.25, 1.5, 2, 2.5, 3, 5, 7, and 10 meters on the other side. There are two sides to each chart. One side displays distances in feet and inches (for example: 3' 10"), the other side displays distances in meters (for example: 1.18 meters). For especially short distances, the distances are listed to the .1 inch level (ex. 1' 10.4") and to the .001 meter level (ex. .782 meters). This information is presented in a clear, easy-to-read format. Each card is laminated to increase its durability and is conveniently sized. The Depth-of-Field charts measure approximately 3.75" x 8.75" (10 cm x 22 cm). For those of you technically inclined and/or curious, the Circle of Confusion used to determine the level of acceptable focus is 0.03 millimeters (mm). This is a commonly used level of measurement that is considered sufficient for prints up to at least 8" x 10" (approximately 20 x 25 centimeters (cm)), and provides a benchmark for higher standards if necessary. Also, precise aperture settings were used in the calculations (example: f/11.31), not the commonly used rounded settings (example: f/11). The format of one chart (the 50mm Depth-of-Field Chart), with examples, is shown below. Of course, the actual charts contain distances for all combinations.
As you can see, the depth-of-field range for a 50mm lens with the aperture set to f/16 and the focus distance set to 6 feet ranges from 4' 6" to 9' 1". All objects within that range will be in focus. The metric side shows that when the focus distance is set to 2 meters, the depth-of-field ranges from 1.46 meters to 3.20 meters. In the examples above, note how using a different aperture setting or focus distance affects the depth-of-field. The depth-of-field also varies considerably from one focal length lens to another. To order your card(s), please refer to the Explore Photography Ordering Instructions. When taking a photograph, only one thin plane of your subject matter will be in perfect focus. The further away an object is from this plane, the less sharp it will be. However, since this loss of sharpness is relatively gradual, there is a distance range in front of and behind the focus plane that will still appear sharp, or in focus. This area is referred to as the depth-of-field range. Objects inside this range are considered to be in acceptable focus. Objects outside of this range are not considered to be in acceptable focus and will therefore not appear sharp in the photograph. Acceptable focus is not a definitive unit of measurement. To understand why, one needs to know that when taking a photograph, many small beams of light pass through the lens. When reaching the film, each of these beams may be thought of as a circle. The smaller this circle is when it reaches the film plane, the more focused the light is considered to be. This circle is often referred to as the Circle of Confusion. At a certain point, this circle is small enough to be considered in acceptable focus. One commonly used level of measurement defines that a level of acceptable focus occurs with a Circle of Confusion diameter of 0.03 millimeters (mm). This is normally considered sufficient for prints up to 8" x 10" (approximately 20 x 25 centimeters (cm)). However, if you have exceedingly high expectations or if you wish to make extra large prints then you may have a slightly higher standard. If so, the common level of measurement still provides a benchmark to work with. Depth-of-field is influenced by three things:
These three factors have a significant influence, and one must be aware of them to obtain the desired depth-of-field. For example, a 24mm lens may easily provide a depth-of-field ranging from two feet through infinity, but a 105mm macro lens, when photographing a close subject, may provide a depth-of-field range as small as 1/16 of an inch! Determining the exact depth-of-field range for each combination of these three factors is difficult. In the distant past, when single focal length lenses and manual cameras were common, most lenses had scale markings on them that one could use to determine the approximate depth-of-field. These have disappeared from most single focal length lenses today. In addition, it is impossible to include these scale markings on zoom lenses due to their variable focal length.
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