Back Button Focus: Why, When & How to Use It
As photographers, we are constantly seeking ways to improve our skills and capture the perfect shot. One technique that has gained popularity among professionals is back button focus. In this article, we will delve into why back button focus is a valuable tool, when to use it, and how to implement it effectively.
Why Use Back Button Focus?
Traditionally, autofocus is activated by half-pressing the shutter button, which is then responsible for both focusing and capturing the image. However, this workflow can be limiting, especially in situations where focus and composition need separate control.
Back button focus separates the focusing and capturing functions by assigning autofocus to a different button on the back of the camera. By doing so, photographers gain several advantages:
1. Flexibility: Back button focus gives photographers greater control over their focus points, allowing them to quickly adjust focus without the need to refocus every time they press the shutter button.
2. Continuous Focus: In scenarios where the subject or the camera is in motion, back button focus enables continuous autofocus. This ensures sharp focus is maintained even when tracking moving subjects or capturing fast-paced action.
3. Eliminating Focus-Recompose Method: With back button focus, photographers eliminate the need for the focus-recompose method, where they focus on a specific subject and then recompose the frame. This method often leads to misaligned focus, particularly with shallow depth-of-field.
When to Use Back Button Focus?
While back button focus can be employed in various shooting situations, there are specific scenarios where this technique truly shines:
1. Sports and Wildlife Photography: Capturing action or fast-moving subjects requires quick and continuous autofocus. Back button focus allows photographers to keep their subject in focus while still being able to make rapid composition adjustments.
2. Portrait Photography: When shooting portraits, having precise control over focus is crucial, especially when working with wide apertures. Back button focus allows photographers to focus precisely on the subject's eyes and recompose the shot without losing focus.
3. Macro Photography: In macro photography, achieving precise focus on tiny subjects can be challenging. Back button focus helps maintain accurate focus during manual focusing and eliminates the need for autofocus in these situations.
How to Implement Back Button Focus?
Implementing back button focus may vary depending on your camera model, but the general process remains similar across most cameras. Here's a step-by-step guide:
1. Customize Autofocus Button: Access your camera's menu and locate the custom function settings. Look for the option to assign autofocus to a different button, typically labeled "AF-ON" or "AE-L/AF-L." Configure this button to activate autofocus.
2. Disable Autofocus from Shutter Button: In the same custom function settings, find the option to disable autofocus from the shutter button. Switch this setting off to ensure autofocus is only activated by the back button.
3. Practice and Familiarize: Take the time to practice using back button focus in various shooting situations. It might feel unfamiliar at first, but with time and practice, it will become second nature.
Back button focus is a powerful and versatile technique that can exponentially improve your focusing capabilities as a photographer. By understanding why to use it, recognizing when it is most beneficial, and learning how to implement it correctly, you will be able to add another valuable tool to your photographic arsenal. So, give back button focus a try and unlock a new level of precision and control in your photography. Happy shooting!
