While zoom lenses are now at their golden age, prime lenses continue to enjoy deep-rooted popularity. Despite having a fixed focal length, prime lenses boast qualities that surpass this disadvantage, some of which are their "bokeh effect," "shake-free images," and "sharp depiction." In the following, I will focus on the "bokeh effect" of prime lenses, and explain techniques on how they can be utilized to capture portraits, a popular genre in photography. (Reported by: Ryosuke Takahashi)
EOS 5D Mark II/ EF50mm f/1.4 USM/ Aperture-priority AE (1/500 sec., f/2.0)/ ISO 100/ WB: Daylight
Recommending use of EF50mm f/1.4 USM
Taking into consideration the shooting distance from the portrait subject, I chose the EF50mm f/1.4 USM, which has a closest focusing distance of about 45cm. With the aperture stopped down to f/2, I blurred the human figures and other objects in the background moderately, while enabling the atmosphere of the location to be conveyed. By making use of manual focus (MF), I was able to establish focus on the right eye, which was not covered by an AF point.
Using Bokeh to Bring Out the Main Theme
Step 1. Set the shooting mode to Av
Turn the Mode Dial to align it with the Aperture-priority AE (Av) mode. In this semi-auto mode, the photographer specifies the aperture value (f-number), while the other settings, including the shutter speed, are determined automatically by the camera. One of the features of the Av mode is that you can control the amount of bokeh easily. This is the mode to use if your emphasis is on the bokeh, as the aperture value does not vary with changes in the brightness of the subject, and the appropriate exposure is determined by altering settings such as the shutter speed.
Step 2. Set the focus mode switch to MF
Select manual focus (MF) for focusing. During manual focusing, you are free to establish focus on any point while you are looking through the viewfinder. It works well in portrait photography, where the photographer needs to move around to compose different shots with the focus set accurately on the eye of the portrait subject. Also, by attaching a bright prime lens with a small maximum aperture value, a bright viewfinder image can be obtained, allowing you to check the focus easily.
Step 3. Hold the camera firmly
In order to achieve precise focus, I rested both my elbows on the table to stabilize the camera. I also paid attention to the area in focus, and made use of the white table as a reflector to reflect light. The surrounding environment is also effectively employed in the shoot, such as by including catchlight in the eyes of the subject while adjusting the brightness of the face.
Step 4. Set focus after determining the composition
I looked through the viewfinder to determine a composition, and established the focus accurately on the right eye. At an aperture value of f/2, which is close to the maximum aperture value of the prime lens, the depth of field (the range of acceptable focus) is shallower than what you would expect. You should therefore have a clear idea which part of the eye you want to set focus on.
Step 5. Control the amount of bokeh with the angle of the face
When photographing the upper body of a portrait subject using a prime lens with a small f-number, a slight change in the orientation of the face alters the position of the bokeh and the resulting impression dramatically. In this example, two shots were taken from the same distance. In the front view, the entire face, particularly the eyes and the lips, appears to be in focus. When the face is tilted sideways, half the face is significantly blurred. In portrait photography, you are also recommended to consider how the position of the bokeh effect varies with the shooting angle, in addition to changes in the depth of field, or the range of acceptable focus.
Column: Learning changes in the skin tone depiction with the f-number
In this example, the EF50mm f/1.4 USM is used to capture a close-up shot of the face from a close distance. Focus was established on the left eye. When the f-number is small, only the eye is in focus while a large part of the skin is blurred, giving a soft impression to the entire image. As the f-number increases, the range of acceptable focus becomes larger, and the skin tone is more sharply depicted. If we look at the four shots, the entire face turns out clear only at f/8, while the hair in the background remains blurred. In the case of general landscape and snap shots, for example, many may have the impression that the entire image would turn out sharp at f/8. However, for photos captured from a close distance, such as portraits, the range of acceptable focus is surprisingly narrow even when the f-number is large. Although you might be tempted to photograph at the maximum aperture value when a prime lens with a small f-number is in use, there is also a greater likelihood that the resulting image would be defocused. Therefore, for portrait shots taken from a close distance, select an appropriate f-number while bearing in mind that sufficient bokeh effect can be obtained even when the aperture is stopped down.
Born in Aichi in 1960, Takahashi started his freelance career in 1987 after working with an advertising photo studio and a publishing house. Photographing for major magazines, he has travelled to many parts of the world from his bases in Japan and China.