Soft, blurry backgrounds are in most cases a great way to enhance the importance of the main subject and to get rid of any distractions in the background. This effect is achieved in digital photography by making use of shallow depth of field.
The range of distance that appears reasonably sharp in a photo is considered as depth of field. The two main factors that affect the depth of field of a photograph are aperture and focusing distance.
The range of distance that appears reasonably sharp in a photo is considered as depth of field. The two main factors that affect the depth of field of a photograph are aperture and focusing distance.
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| Photo by Tibchris |
Aperture
The relationship of aperture and depth of field is pretty simple to remember. Smaller aperture values (Larger f-stop numbers) produce greater depth of field and vice versa. So in order to achieve shallow depth of field in your digital photos choose Larger aperture values (Smaller f-stop numbers). Smaller the f-stop shallower the depth of field.
Greater depth of field – f 16, f18, f22 etc.
Shallow depth of field – f1.8, f1.4, f1.2 etc
Aperture Priority Mode
An easy way to get shallow depth of field in your digital photos is to switch your camera to aperture priority mode and choose Smaller f-stop numbers. (f1.2, f1.4, f1.8 etc) your camera will automatically select the best shutter speed for the selected f-stop and expose the shot perfectly producing beautiful soft, blurry backgrounds.
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| Photo by Dr_Tr |
Focusing Distance
In digital photography focusing distance refers to the distance between the camera and the subject that is being shot. Depth of field increases when focusing distance increases and vice versa. So in order to achieve shallow depth of field in your digital photos consider reducing the distance from the subject to your camera.
In reality for keeping the magnification factor constant when altering the focusing distance what you will be doing is to move away from the subject and use a longer focal length lens set to its smallest f-stop value.
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| Photo by John & Fish |
There is a common misconception that using a zoom lens produces shallow depth of field in digital photography. But in reality, depth of field for a given focal length is the same for both zoom lenses and wide angle lenses. To realize this you need to shoot a subject with a zoom lens and a wide angle lens. Remember to keep the magnification constant. Meaning you will need to get much closer to your subject to shoot it with your wide angle lens at the same magnification as the zoom lens you used. Compare the two shots and you will realize that if the subject magnification is same depth of field for both lenses is also same.
Distance between subject and the Background
The closer the subject is located to its background, the lesser the blur. So move the subject as far away from the background as possible to achieve maximum background blur.
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| Photo by Raymond Larose |
Pre-set Camera Modes to Achieve Background Blur
Portrait Mode
If you do not want to concern yourselves with the f-stops values and all select the Portrait Mode (symbol for portrait mode is a head) in your camera. In this mode the camera automatically selects smaller f-stops and exposes accordingly.
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| Photo by John & Fish |
In the next article we will discuss about Photography - How To Photograph - How to Recover deleted photos from Camera's Memory Card