Tutorials: Basics
Depth of Field
When you have your digital camera focused on a set subject, everything at the same distance (within a close proximity) will be equally in focus. Objects closer or further away will be less sharp or less in focus. The closer or further away an object is from the focused area, the less sharp that object will be in a picture. The area where objects are "in focus" or sharp enough for the human eye to still perceive as "focused" is referred to as "Depth of Field".
Field of Depth can also be manipulated via aperture/F-stop
settings. An example of this may be seen below. In the picture you should note
that while the subject is in focus, the background is blurred out - that is the
side-effect of an "open" shutter (f2.8 in this case) and what's referred to as a
"narrow" depth of field since the area in focus is relatively narrow.
The next image is utilizing a wide aperture setting. An image with a wide aperture is referred to as having a "wide" depth of field (the area in focus is wide). Portraiture (as referenced above) often calls for a narrow depth of field to help keep the distracting background from overwhelming the subject, whereas landscapes (below) often call for a wide depth of field, so the entire landscape is sharp and visible.
When you have your digital camera focused on a set subject, everything at the same distance (within a close proximity) will be equally in focus. Objects closer or further away will be less sharp or less in focus. The closer or further away an object is from the focused area, the less sharp that object will be in a picture. The area where objects are "in focus" or sharp enough for the human eye to still perceive as "focused" is referred to as "Depth of Field".
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An example is to the right. The Blue "X" is the subject. The Pink section is
the focus zone, or the area where objects will still be sharp in the picture.
As you can see, as objects get further away they will become out of focus or lose
sharpness in the image. While the green object is still discernable, the dark red
object will be blurred in the background. The opposite is also true with objects
closer to the camera. Depth of field also effect linear objects as expressed by
the red objects on the ends.
You can test this yourself by simply looking at a close object and noticing that objects surrounding your focal point are not as sharp or blurred. Now, focus on an object across the room. You will notice that more objects are now within the Focus Zone yet you still have blurred objects closer to you and further away from the subject you are focused on. |
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The next image is utilizing a wide aperture setting. An image with a wide aperture is referred to as having a "wide" depth of field (the area in focus is wide). Portraiture (as referenced above) often calls for a narrow depth of field to help keep the distracting background from overwhelming the subject, whereas landscapes (below) often call for a wide depth of field, so the entire landscape is sharp and visible.