Depth of Field | a 7 Image Story

Depth of Field | a 7 Image Story  Depth of Field: the distance between the nearest and the furthest objects in acceptably sharp focus in an image.  Seems like a simple enough concept!  Applying this simple concept might be a bit more difficult than it seems.  To help visualize DoF, these 7 images of a difficult subject at t different f-stops (f1.4, f2, f2.8, f4, f5.6, f8, f16) show the impact of small aperture changes.

The three main factors that affect the control of depth of field are aperture (f-stop), distance to the subject from the camera, and focal length of the lens.  The higher the f-stop, the larger the depth of field.  The shorter the distance between camera and subject, the shorter the depth of field.  The longer the focal length of the lens, the shallower the depth of field.

This post will only show how changes to aperture affect depth of field.  Aperture is the diameter of the hole through which light enters the camera’s sensor or film.  The aperture size (f-stop) controls the amount of light entering the camera.  The lower the f-stop number, the smaller the depth of field.  The higher the f-stop, the larger the depth of field.  Notice how the DoF in the crabapple blossoms continues to get deeper going from f-stop f1.4 to f2 to f2.8 to f4 to f5.6 to f8 to f16.  As the f-stop number goes up, the aperture hole gets smaller; letting in less light.  Notice, as the f-stop goes up, the shutter speed may get slower and/or the ISO get higher to maintain the correct exposure.  In these 7 images, my camera was set to Aperture Priority and Auto ISO.  When the aperture f-stop was increased, the camera set the shutter speed and ISO.

Controlling DoF can turn an everyday snapshot into a very nice image.  In this case, both the f2.8 and f4 images are pleasing to me.  They make the foreground cluster of blossoms stand out from the busy flower background.  All 7 images were captured at approximately the same distances from camera to subject.  However, the Nikon 1 V3 has a 2.7 crop factor so the 50mm f1.4 lens becomes 135mm.  Thus, the images all have some compression; reducing the DoF a bit for all f-stops.

Crabapple Blossoms f1.4   An f-stop set to f1.4 produces a very narrow depth of field.  Only the very front of the lighter flowers are in sharp focus.  Even the second tier of flowers show some blur.  F1.4 can produce some dramatic images by isolating a small area in the frame.  In portrait images, one eye can be in focus while the other isn’t.  In wildlife photos, f1.4 isolates the eye.  In insect images, it isolates the insect from its surroundings.

Crabapple Blossoms f2   An f-stop set to f2 still produces a very narrow depth of field; just a tad deeper than f1.4.  Now, the very front flowers and some of the second tier are in sharp focus.  F2 can produce some dramatic images by isolating a small area in the frame.  In portrait images, one eye can still be in focus while the other isn’t; depending on the angle from camera to the face.  In wildlife photos, f2 still isolates the eye.  In insect images, it isolates a larger insect from its surroundings.

Crabapple Blossoms f2.8   An f-stop set to f2.8 still produces a reasonably narrow depth of field; just a little deeper than f2.  Now, the entire cluster of flowers in the foreground are in sharp focus.  F2.8 isolates a medium size area in the frame.  In portrait images, the entire face is in focus.  In wildlife photos, f2.8 still isolates the entire head.  In insect images, the insect and some of its surroundings are in focus.

Crabapple Blossoms f4   An f-stop set to f4 produce a little deeper DoF than f2.8.  Now, the entire cluster of flowers in the foreground are in sharp focus and the background out of focus flowers have a bit more definition with deeper color.  In portrait images, the entire head and shoulders is in focus.  In wildlife photos, f4 still isolates the entire head and shoulder.  In insect images, the insect and much of its surroundings are in focus.

Crabapple Blossoms f5.6   An f-stop set to f5.6 produces a little deeper DoF.  Now, the entire cluster of flowers in the foreground are in sharp focus as well as a few background flowers.  The background out of focus flowers have a even more definition.  In portrait images, the entire person as well as some of the surroundings are in focus.  In wildlife photos, f5.6 most of the animal and maybe some surroundings are in focus.  In insect images, the insect and all of its surroundings are in focus unless the background is far away.

Crabapple Blossoms f8   An f-stop set to f8 produces a fairly deep DoF.  Now, the entire cluster of flowers in the foreground are in sharp focus as well as a few far background flowers.  The background out of focus flowers have a even more definition.  If the lens was not a 135mm telephoto, the background flowers would very likely be in focus.  In portrait images, the entire person as well as some of the surroundings and background are in focus.  In wildlife photos, f8 all of the animal and most of the surroundings as well as the background are in focus.  In insect images, the insect and all of its surroundings and background are in focus.

Crabapple Blossoms f16   An f-stop set to f16 produces a very deep DoF.  Now, the entire cluster of flowers in the foreground are in sharp focus and the far background flowers are a bit more in focus.  The background out of focus flowers have a even more definition.  If the lens was not a 135mm telephoto, the background flowers might be in better focus.  However, at f16 and higher f-stops, light infraction may soften the sharpness rather than make the image sharper.

Each image will be posted individually this week with a bit more narrative under category Depth of Field.

Click any image below for a slide show!