Single autofocus is useful when subject distance stays still; continuous autofocus is intended to keep adjusting as distance changes. Choosing between them is less about the camera and more about whether your subject, or you, will move before the shutter is pressed.
What to do
Start with a clear subject and an appropriate focus area. Use single AF for a stationary test, then continuous AF for an approaching subject. Inspect the intended subject plane instead of judging from the small preview.
Zoom into the playback image and look at the exact detail you meant to focus on, such as an eyelash, a label or a leaf edge. A frame can look acceptable at thumbnail size and still be focused slightly in front of or behind the target.
Matching the mode to the subject
These rules of thumb help you pick a starting point:
- Single AF: landscapes, buildings, products, posed portraits and anything that will not move before you shoot. It locks focus when achieved and often will not fire until it does.
- Continuous AF: children, pets, sport, street scenes and any situation where you or the subject are moving.
- Automatic switching modes: some cameras decide for you. They can be convenient, but they are less predictable, so test before relying on them.
Also consider the focus area. A small area gives precise control over what is sharp, while a wide area is quicker to use but may pick the nearest high-contrast object.
A mistake to avoid
Changing AF mode alone does not select the right subject. A large automatic area can still choose the background or another person. Pair the mode with a sensible area and, where available, subject selection.
A detail worth checking
Continuous AF does not require a long burst every time. Separate the choice to track distance from the choice to record multiple frames. Practice controlling both so you can respond without changing unrelated settings.
Try this practical check
Photograph one stationary object and one walking person. Record which mode, area and subject selection produced the most consistent intended focus. Repeat with a different light level, because tracking often struggles more in dim conditions.
Common questions
Can I use continuous AF for still subjects?
Yes, but it may keep hunting slightly or refocus after you recompose. For a fixed subject, single AF is usually more predictable.
Why does single AF sometimes refuse to take a picture?
Many cameras are set to release the shutter only after focus is confirmed. Check your menu for the setting that controls this priority.
Does continuous AF drain the battery faster?
It can, because the focus system keeps working while you hold the button. The effect varies by camera, so watch your battery during a long session.
Related reading
How to Choose a Camera Lens: A Simple Guide (2026)
