AF – Auto focusing is one of the most common questions I get from students
Why does the area that ends up sharp often differ from what the photographer intended?
First, it’s important to understand that a photograph is a flat, two-dimensional image. When your camera focuses, it locks onto the closest plane. The camera doesn’t know if you want the foreground or background to be blurred.
To take better control of focus, you can
1/ Manually select the focus point: choose exactly where you want the camera to focus.
2/ Center your subject. Focus on it. Then recompose by placing the subject in the center. Lock the focus. Finally, adjust your composition while keeping the focus locked.
Let me share a few examples using butterflies as my subject. I use Single-Point Spot AF for small subjects.
Example 1
The focus landed on a leaf instead of the butterfly. I only noticed this after taking the shot. When you use a wide aperture, such as f/1.2 to f/2.8, the area in focus becomes very shallow or narrow.
The quickest fix? I was shooting in continuous mode. I moved the camera back and forth until the butterfly was in focus. Adjusting settings was not practical, because the butterfly moves quickly. For slower subjects, such as landscapes, you usually have more time to fine-tune.
Example 2
The butterfly is in focus, but so is a nearby leaf. This happens because objects at similar distances fall on the same focusing plane, causing multiple points to be sharp. Sometimes this can distract viewers from your main subject.
To fix this, I stepped back and slightly rotated the camera to bring the butterfly closer to the lens. This change enabled me to use a shallow depth of field. I could blur the surrounding elements and make the butterfly stand out clearly.
Example 3
Keep in mind, at aperture f/2.2, only a small portion of the image is in focus. This can create the illusion that most of the photo is out of focus. Ideally, you want both the flowers and the butterfly in focus simultaneously.
I adjusted my position and camera angle. I did this to keep the flower and the butterfly on the same focal plane. This keeps both subjects acceptably sharp.
Autofocus works best with plenty of light and contrast. Cameras detect edges and textures by analyzing the light reflected from your subject.
When there is plenty of light, the camera can easily distinguish shapes and edges. This helps it lock onto the correct focus point. In low light or flat scenes, your camera will hunt for focus or miss the mark.
Always review your shots on playback so you can make adjustments while you’re still out shooting.
Ultimately, photography is more than mastering settings. It’s about seeing the subtle details. It involves embracing spontaneity. It also means trusting your experience to bring each image to life.