Introduction

In this blog post I am going to cover back button focus. This is a very common technique used by wildlife photographers. But again, the main objective of this blog post is to explain the advantage of back button focus. I have been using canon camera from the beginning but my assumption is that this functionality is available in all major DSLR/mirrorless brands.

I am not going to cover how to enable that setting as it will vary depending on the brand as well as camera model. Camera manual will have all this information.

Why Back Button Focus?

Traditionally, any camera has shutter and focus functionality attached with the same button. So when you half press a shutter button, it will focus and then when you fully click it, it will capture the image. Most of us start with this when we start our DSLR journey.

So in simple words, back button focus will isolate the focus and shutter functionality. So a separate button will be used for focusing and shutter (Clicking an image). This allows better control over the frame and hence the overall composition.

Explaination

So a simple case, I would like to mention here. Most entry level DSLR have the best autofocus point (cross-type for canon) in the center. In theory, it is faster as compared to other focusing points. So in order to frame a subject as per rule of third, you have to select some other point then the center point. If you want to focus using the center point without back button focus, you will struggle a bit to maintain the exact focus when you make adjustments to the frame.

General flow of shooting

Focus -> Frame -> ShootNow

when using the conventional method, we may not be able to maintain the focus on the subject properly which results in an out of focus image. Here we press the shutter halfway, make adjustment (Here unintentionally, you can be focusing at some other place) and then click.

With back button focus, you are technically locking the focus and then you have all the freedom to frame the image. Once you have finalized the frame then press the shutter. So focus using the center focusing point, release the focus button, make adjustment to the frame and then click the image.

Conclusion

I feel this is a very powerful tool which can help you get sharper images. Initially it may be a bit of a hassle to adjust to the back button focusing. But in my opinion, it’s about muscle memory. You should ideally operate the camera without taking your eyes off your viewfinder. With time you can obtain that muscle memory and the camera as designed in such a way that it gets easier to change the settings without looking at the LCD/Display. Once you get used to the back button focusing, you may not go back to the conventional way of shooting. At the end of the day, it is a personal preference.