Ron Bigelow Photography Articles
How To Use Depth Of Field To Create Great Photos
by Ron Bigelow
When we, as photographers, plan a shot, one of the fundamental decisions that we must make is what we want to be in sharp focus. What we desire to be in focus can vary radically from one image to another. For an expansive vista of the Grand Canyon, we may desire that everything from the foreground to the farthest recesses of the canyon be sharp. For a macro shot of a flower, we may want a very narrow range of focus so that the viewers' attention is concentrated at a specific point in the image.
The issue of what is and is not in focus is referred to as depth of field. From a practical point of view, depth of field can be defined as the nearest point to the farthest point that appears sharp in an image. So, the question now becomes, ?How can we control the depth of field?? Actually, there are several factors that we can control that will affect the depth of field.
Selecting the Aperture
One of the best ways to control the depth of field is through the selection of the aperture. Large apertures create photos with a small depth of field. On the other hand, small apertures create photos with a large depth of field.
Focal Length and Depth of Field
Long focal length lenses reduce the depth of field while short focal length lenses increase the depth of field. Ever notice that landscape photographers tend to use wide angle lenses combined with small apertures a lot? One of the reasons is that this combination creates a very large depth of field.
Distance
The farther away the camera is focused, the larger the depth of field that will result.
Lens Sharpness and Depth of Field
Choosing a sharper lens will create a greater depth of field. This is because sharper lenses are sharper at all points. This results in a larger depth of field.
Sensor or Film Size and Depth of Field
The sensor or film size is a bit more complicated with respect to depth of field. Images that come from cameras that use larger sensors or film require less enlargement when a print is made. Less enlargement results in a sharper print which increases the depth of field. However, larger sensors or film usually mean that a longer lens is going to be used. This decreases the depth of field. So, what is the final verdict on this one? More often than not, cameras with larger sensors or film size will give a smaller depth of field, but this is a guaranteed thing. The overall impact on the depth of field depends a lot on how the camera is used.
Print Size
The larger you print, the smaller the depth of field that will result. Larger prints require more enlargement which results in a lessening of the sharpness. Consequently, the detail in the print is softened, and the depth of field is decreased.
A Special Distance
When it comes to the focus distance, there is one very special focusing distance called the hyperfocal distance. The hyperfocal distance is the shortest distance from the camera such that everything from approximately half that distance to infinity will appear sharp. Focusing the camera at the hyperfocal distance results in the greatest depth of field possible for a given combination of aperture and focal length.
One of the easiest ways to determine the hyperfocal distance is to use a depth of field guide. Depth of field guides are inexpensive, small, and light. They allow a photographer to determine the hyperfocal distance along with a number of other depth of field parameters.
Photographers that have older lenses may find depth of field scales on the lenses. Setting the hyperfocal distance with these lenses is easy. All you need to do is align the infinity symbol with the depth of field lines (generally, the depth of field lines are colored).
Summation
Now that you have control over the depth of field, it is time to use that information to create some dynamic images.
Interested in finding out more about depth of field? Check out Ron's full length depth of field article at Depth of Field. In addition, if you are interested in becoming a master photographer, check out the secrets to taking great photos by visiting Ron's free site at Ron Bigelow Photography.
Selecting the Aperture
One of the best ways to control the depth of field is through the selection of the aperture. Large apertures create photos with a small depth of field. On the other hand, small apertures create photos with a large depth of field.
Focal Length and Depth of Field
Long focal length lenses reduce the depth of field while short focal length lenses increase the depth of field. Ever notice that landscape photographers tend to use wide angle lenses combined with small apertures a lot? One of the reasons is that this combination creates a very large depth of field.
Distance
The farther away the camera is focused, the larger the depth of field that will result.
Lens Sharpness and Depth of Field
Choosing a sharper lens will create a greater depth of field. This is because sharper lenses are sharper at all points. This results in a larger depth of field.
Sensor or Film Size and Depth of Field
The sensor or film size is a bit more complicated with respect to depth of field. Images that come from cameras that use larger sensors or film require less enlargement when a print is made. Less enlargement results in a sharper print which increases the depth of field. However, larger sensors or film usually mean that a longer lens is going to be used. This decreases the depth of field. So, what is the final verdict on this one? More often than not, cameras with larger sensors or film size will give a smaller depth of field, but this is a guaranteed thing. The overall impact on the depth of field depends a lot on how the camera is used.
Print Size
The larger you print, the smaller the depth of field that will result. Larger prints require more enlargement which results in a lessening of the sharpness. Consequently, the detail in the print is softened, and the depth of field is decreased.
A Special Distance
When it comes to the focus distance, there is one very special focusing distance called the hyperfocal distance. The hyperfocal distance is the shortest distance from the camera such that everything from approximately half that distance to infinity will appear sharp. Focusing the camera at the hyperfocal distance results in the greatest depth of field possible for a given combination of aperture and focal length.
One of the easiest ways to determine the hyperfocal distance is to use a depth of field guide. Depth of field guides are inexpensive, small, and light. They allow a photographer to determine the hyperfocal distance along with a number of other depth of field parameters.
Photographers that have older lenses may find depth of field scales on the lenses. Setting the hyperfocal distance with these lenses is easy. All you need to do is align the infinity symbol with the depth of field lines (generally, the depth of field lines are colored).
Summation
Now that you have control over the depth of field, it is time to use that information to create some dynamic images.
Interested in finding out more about depth of field? Check out Ron's full length depth of field article at Depth of Field. In addition, if you are interested in becoming a master photographer, check out the secrets to taking great photos by visiting Ron's free site at Ron Bigelow Photography. 