Focusing constitutes one of the basics in photography, and determines the result of your photos. While focusing work might be straightforward, you are advised to gain a thorough understanding of the fundamentals and learn to perform precise focusing through practice. (Reported by: Ryosuke Takahashi)
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Understanding the Mechanism to Perform Proper Focusing
Most digital SLR cameras in the market today are built in with an "autofocus (AF)" mechanism, a handy feature that allows focus to be achieved simply by pressing the shutter button. That being said, the photographer needs to have a clear "intention" of where to set the focus, as the camera is not designed to establish focus automatically on the desired point in an image. Focusing should be performed correctly upon gaining an understanding of this logic.
AF Point / Point to establish focus during AF
Points where AF can be established are indicated by the square AF frames on the viewfinder screen. In the auto selection mode, the point where focus is achieved is illuminated in red together with a "beep" sound. You can also set the focus by selecting one of the AF points manually.
Choose where you want to set the focus on
[1] Direct the camera at the subject and press the shutter button down halfway
When the shutter button is pressed down halfway, the autofocus mechanism is activated, and focusing starts.
[2] Focus falls on an unintended point
A "beep" sound is heard, indicating that focus is achieved. However, in the auto AF point selection mode, focus automatically falls on the object closest to the camera.
[3] Press the AF point selection button
If there is a point where you want to establish focus on, press the AF point selection button.
[4] The AF points light up in red
Upon pressing the AF point selection button, all the AF points light up in red.
[5] Turn the Main Dial
Turn the Main Dial to select one of the illuminated AF points manually.
[6] Move the red AF frame
While looking through the viewfinder, turn the Main Dial to move the red AF frame, and stop at the position you want to set focus on.
[7] Press the shutter button down halfway again
Press the shutter button down halfway again to set the focus. Upon hearing the "beep" sound and checking the viewfinder image, press the shutter button all the way down to take a photo.
Selecting an AF Mode According to the Movement of the Subject
When using AF for focusing, it is important to select the most appropriate mode according to the subject you want to capture. Canon's EOS series offers three types of AF modes with factors such as the movement and speed of the subject taken into consideration.
Press the "Q" button to display the Quick Control menu. Select an AF mode (default setting: One Shot), and press the "Q" button again.
In the One Shot AF mode, the autofocus mechanism stops when focus is established on a specific object, and the focus position is temporarily fixed. This is a versatile feature suitable for subjects with little movement.
ONE SHOT
In the One Shot AF mode, the autofocus mechanism stops when focus is established on a specific object, and the focus position is temporarily fixed. This is a versatile feature suitable for subjects with little movement.
Suitable for
- Portraits
- Landscapes
AI SERVO
AI Servo is an AF mode that maintains the focus on the subject automatically while the shutter button is pressed down halfway. It is suitable for photographing moving objects, and is able to maintain the focus on the subject even when it is approaching the camera at a high speed.
Suitable for
- Sports
- Animals
AI FOCUS
One of the characteristics of AI Focus is that multiple AF points are used simultaneously for focusing. Also, it switches automatically to AI Servo according to the movement of the subject, and is thus useful for subjects with unpredictable movements.
Suitable for
- Street photography
- Children
Restore the settings when you are done
After you have captured photos using a manually selected AF point, remember to restore the AF point selection setting. All the AF points should light up when they are in the auto selection position. Aligning the manually selected AF point to the centre helps to reduce the hassle when you start the next shoot. Nonetheless, you can select a home position according to your preference.
When an AF point is selected, you can switch to another AF point by turning the Main Dial.
The position where all the AF points are illuminated is the auto AF point selection position.
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. Takahashi is a member of the Japan Professional Photographers Society (JPS).
