Depth of Field (DOF), one of the photography basics, is how much of the scene in your photograph is in focus. It is the scene in front of and behind the focus point in your picture which looks decently sharp.
Factors that affect Depth of Field include Aperture, Distance between you/camera and the subject photographed and the Focal Length of your camera lens.
Relationship between Aperture and Depth of Field
Aperture is the opening that lies between the lenses of the camera that allows light to enter the image sensor.
Wider you set the aperture opening, more light will enter the image sensor and vice versa.
Aperture is measured in f-stop or f-number. Aperture opening and f-stop (f-number) are inversely related. Wider the aperture opening, smaller the f-number; smaller the aperture opening, larger the f-number.
For instance, if you click a photograph using aperture of say f/4 (small f-number and wide aperture opening), you will be able to see the subject clearly in your snap but the backdrop will appear blur which is known as Shallow depth of field.
And if you take a snap using aperture of say f/16 (large f-number and small aperture opening), the subject as well as the backdrop in your photograph will be clearly visible which is known as Deep depth of field.
Wide Aperture opening = Small f-number = Shallow depth of field
Small Aperture opening = Large f-number = Deep depth of field
How does Distance control Depth of Field
The closer your DLSR camera is to the subject, shallower will be the Depth of Field. Farther your DLSR camera is to the subject, deeper will be the Depth of Field. Hence, maintain the distance between the DLSR camera and the subject being photographed according to your creative purpose.
How does Focal Length of your DSLR Lens control Depth of Field
Focal length will vary depending on how you adjust the camera lens while photographing a scene. For example, in a Canon EOS 1500D DSLR Camera, if you shoot with a wide angle lens, say using 18mm lens, your photo will have a Deep Depth of Field. And if you zoom the lens to 55mm to photograph the scene, your image will have a Shallow Depth of Field
We bring you ‘Jo & His Camera’ Comic Strips wherein a Magical Camera gives DSLR photography tutorials to Jo.
To understand Depth of Field, Click on the below Image to see the Comic wherein the Camera explains Jo, the concept of Depth of Field.
Bokeh, a Japanese word, means blur produced (by the lens) in the out-of-focus area of a photo that lie outside the Depth of Field. Bokeh are circular shapes created while photographing a scene with a wide aperture opening, say f/2 (Shallow depth of field) when the lens display out-of-focus points of light.
You can create Bokeh in Portrait Photography if you use wide aperture (shallow depth of field) to make the subject stand out against a blur backdrop. Alternatively, you can also produce Bokeh effect using a small aperture only in cases when the backdrop is far enough.
Click on the below Image to see the Comic wherein Jo experiments with different Camera Settings and succeeds in mastering Depth of Field.
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