By : Nikon School Blog | 29 Sep, 2016 |
Imagine taking a great image, and after zooming in later, finding out that it lacks sharp focus. Or imagine covering an important event and finding it hard to focus on the main subject. Many important and potentially great images have been ruined by lack of sharpness. In most of the cases, lack of understanding of the focus modes have been the cause. With proper understanding of the focusing systems used in modern Nikon D-SLRs, you can easily prevent common focus problems, and always get sharp images.
Wrong focus mode used
If you are using AF-S (single servo) mode with a moving subject, the camera locks focus when you half-press the shutter release button. If the subject moves while focus is locked, it will get out-of-focus as its distance will change from where focus is locked.
Similarly, if you are using AF-C (continuous servo) mode with a static subject, like a posing portrait, focus may change if you move the camera after focusing on the subject, or if something else comes between you and the subject.
It is best to use AF-S for static and AF-C for moving subjects. In case of doubtful movements, use the default AF-A (auto) option.
Wrong focus point used
The focus area mode menu of Nikon D-SLRs, allows us to instruct the camera where to focus. The most common mistake is when a single or dynamic point is chosen but placed wrongly somewhere other than the subject. The dynamic point is meant for use with moving subjects. If you place the dynamic point at a wrong position, then the main subject will not be focused properly.
Try to put the single or dynamic point right on the subject. Do ensure that the point is falling on a bright area which has contrast. Placing the single or dynamic point at a blank area, like someone's hair, or plain clothes, or the sky makes it difficult or impossible for the camera to lock focus.
Choosing auto area
Auto area is the default system and it works well for most situations. However, to ensure that the camera focuses on the intended area, you must ensure that the subject is fairly visible in the frame. It should not be too small, or too dark, or merging with the foreground or background. If anything other than the subject stands out more than the subject, the chances are high that the camera will focus on it rather than the subject.
Lens focus selector
Though this one may sound very silly, but it happens quite frequently. Many photographers forget to check the lens focus selector or A/M switch during an intense shoot, and if the switch is set to M, then there will be no focus, and the vital moment might have gone.
Camera focus selector
Nikon camera bodies other than D3000 and D5000 series have a focus selector switch on the body. This needs to be in 'AF' position for autofocus. If your camera has it, always check its position before shooting.
Too close to the subject
Every lens has a minimum focusing distance. It is usually mentioned in the specifications and also on the lens body or indicated by the distance scale on some lenses. If you try to focus at a distance closer than that, you will end up with out of focus images. You must be aware of the minimum focusing distance of your lens to avoid this situation.
Apart from these common focus problems, there may be a genuine technical problem with the focus system in the lens or the camera. If you've crossed out all the above points and still facing focus problems, then head to any authorised Nikon service Centre for an inspection.