Focus – The measure of sharpness

Manual focus is advisable for the greatest degree of control & accuracy. Autofocus can be useful for quick adjustments when needed, but can struggle where lots of movement occurs, such as in dance. There are a number of factors which determine how much range you have with focus, including aperture, focal length & camera distance from subject.  

Always ensure your focus is checked both in the initial set up and monitored throughout where possible. 

Infinity ∞ – The infinity point is where a focus point in the distance where everything from that point and beyond remain at an acceptable level of focus. When light becomes more collimated (parallel), light from point sources cannot be discriminated from light originating from a point source that is infinitely far away, as a result all light sources appear to be in focus. Any object which is situated between the lens and this point is subject to depth of field and focus. 

AF-S – Autofocus usually involves touching the screen on the subjects where you would like the camera to focus. The focus will remain at that distance until the screen is tapped again when required. Some cameras have options such as Area / Pin Point depending on how specific your focus needs to be. 

AF-C – Continuous Autofocus, often used in video, is where the camera will continuously analyze the scene and will try to keep a moving subject within the defined area in focus. This can be useful a feature for slow moving subjects, or where the subject remains within the defined autofocus area but can be tricky when you have a subject or subjects moving through the frame regularly or quickly. Other continuous autofocus settings include options like Face Detect and Subject Tracking, where the camera is looking to keep faces or a chosen subject in focus and follows them around the frame adjusting the focus accordingly.

Manual – Manual Focus gives you the most control of the focus of your subject, it lets you choose if you want the focus to be soft or sharp, and also the speed at which the transitions happen. Manual focus usually involves turning a dial located on the lens.