All compact digital cameras have problems automatically focusing at times. Many autofocus systems are contrast based and need contrast between the edges of a subject and its background to lock focus.
Even if a camera has an autofocus assist beam, it may not focus properly in some situations. When contrast is not found, a camera will “hunt” until it is able to lock focus on an edge with contrast.
Causes of autofocus problems
Besides low-contrast subjects, there are other situations that prevent a digital camera from properly focusing. They include:
- Overlapping nearby and distant objects
- Very bright subjects in the center
- Subjects moving very fast
- Texture of the subject is very busy
- The color of a subject and the background are very similar
- Photographing subjects through glass
- Taking pictures out of the camera’s shooting range
- Smudges on the front of the lens
Solutions for autofocus problems
When your digital camera fails to achieve focus, try some of the following:
- Make sure you’re within shooting range; if you’re not sure what it is, get closer or move further from the subject and focus again.
- Change your photo-taking angle.
- Lock focus on item with contrast that is same distance as the main subject, then recompose before pressing the shutter button down fully.
- In the case of a fast moving subject, prefocus on something of similar distance, then track the subject and press the shutter button when it’s in view.
- If you’re zoomed in on a subject, zoom out (wider angle) in increments until focus lock is achieved.
- If you’re inside, increase the room lighting or use a flash.
- Try a different focus mode. Most compact digital cameras have two focus modes: single area focus and continuous autofocus.
- If you camera has the ability to focus manually, do so.
- If the camera lens is coated with smudges, clean the lens.
The photo of the eagle is an example of a subject on which it’s difficult to lock focus when solely relying on autofocus. Lighting was low, there is not a lot of contrast in the main area you want to be in focus (the eye), and the texture of the main subject is “busy.”
Focus was achieved by locking focus off-center in the high contrast area indicated by the X. When focus was locked, the photographer recomposed.
It took more than one attempt of lock focus.
Related reading: DSLR compose then focus