How to nail focus every time

It's the easiest way to ruin a photo, and something we've all done at some point - we've taken a shot, had a quick look at the photo on the screen of our camera, but when we look at it more carefully when we get home we realise that the camera has focussed in the wrong place, or hasn't achieved focus properly and the image is blurred. It's so easy to get wrong, especially of you leave it up to the camera to focus for you, yet most cameras come armed with an array of features to help you to nail your focus every time. In this article we will look at just a few of these features. 

There are three types of blur

Although it's not always easy to tell by looking at a photo, there are actually three main reasons why some or all of a photo might be blurred; the first is that it is not correctly focussed; the second is that the camera has moved while the photo was being taken (camera shake) and the third is that the subject has moved whilst the photo was being taken (the latter two are usually only when a slow shutter speed has been used).

In the left photo below, I have ensured that the camera is focussed on the front flower (my chosen main subject) and so it is nicely in focus. In the middle photo, the camera has focussed on the flower in the background meaning that my main subject is blurred (usually not a good thing!). In the right hand image, the main subject was in focus, but my shutter speed was too slow, meaning that the camera moved whilst I was taking the photo! 

Incorrect focus usually means that some of the photo is in focus, and some of it is blurred (I moved the camera intentionally to emphasise it, so this is actually a genre called Intentional Camera Motion, ICM photography!). 

Camera shake usually means that all of the photo is blurred. 

If blur is due to the subject moving while you're taking the picture (not relevant in the example below), usually only the moving object will be blurred.

The remainder of this article deals with the first of these reasons for blur; making sure you nail the focus correctly!

What tools does your camera provide to help nail focus?

Some of the tools we will look at are available on most cameras, whilst others are only available on a smaller subset of cameras. You will need to check your camera manual to understand which of these are available to you. All of the methods below are more accurate that just leaving it up to your camera to decide where to focus, but the most accurate (especially in difficult light conditions) is using manual focus. Most cameras will have a manual focus option, but only some cameras will have auto zoom and focus peaking which ensures the best focus is achieved. Note that these methods are especially important when using a narrow depth of field (large aperture) as there's much less room for error ensuring that your main subject is in focus.

1. Use touch screen focus

2. Use point or area auto focus

3. Use manual focus + auto zoom + focus peaking

1. Use touch screen focus

If your camera has a touch sensitive screen (all camera phones and many compact, bridge, DSLR and mirrorless cameras do) then you can simply touch on the screen where you want the camera to focus. This is more precise than using full auto focus, where the camera decides for you.

2. Use point or area auto focus

Many cameras allow you to specify a point, an area or a zone where you want the camera autofocus system to focus. These methods allow you to achieve a more accurate and specific focus than simply leaving it up to your camera to decide where to focus. More detail on these methods can be found on my previous blog on auto focus points and areas. 

3. Use manual focus (+ auto zoom + focus peaking if available)

Manual focus is when you override the camera autofocus and manually turn the focus ring on the lens to decide on the plane of focus (what's in and out of focus). Although it's potentially the most accurate way of ensuring your subject is in focus, it can be a bit slow and difficult to get right and therefore I don't recommend using it all of the time. However, there are some specific situations where I always turn manual focus, these are:

- When taking photos of the night sky. Camera autofocus systems do not perform well in low light and can struggle to focus on stars; I therefore switch to manual in this situation.

- When taking macro photos. When taking photos of small objects close up, and usually using a small aperture, it's normal to find that the depth of focus is so narrow that only parts of the subject can be in focus at any one time. In situations like this, when it's essential to get the correct part in focus (e.g. the centre of the flower or the eyes of the bug) I would switch to manual focus. 

How to use manual focus

1. First switch your focus to Manual; this can either be done by a switch on the lens body (usually a toggle between AF [AutoFocus] and M [Manual]) or by changing the Focus Mode in the camera menu.

Pro Tip: I assign one of my camera function buttons to be a toggle between Autofocus and Manual focus so that I can switch between these modes at the press of a button

2. Turn the focus ring on your lens until your subject (or the part of the scene that you want in focus) is in crisp focus. Whilst this is simple in theory, it can be difficult in practice to see on a small camera screen when you have the right area in focus. This is when Auto Zoom and Focus Peaking functions can really help (if your camera has them).

Auto Zoom (also called AF Assist or Focus Magnifier): 

This is a camera menu setting that automatically zooms into the scene when you are on Manual Focus and turn the focus ring. You can usually move the small area that you are zoomed into using the Left-Right-Up-Down arrows. This means that you can see the scene in detail which makes it easier to see when you have achieved the correct focus.  

Focus Peaking: 

When Manual focus is enabled, areas of the scene that are in crisp focus are outlined in a bright colour (usually red or yellow which can be changed in your camera settings). If your camera has this ability, you may need to activate it in your camera menu. 

Final words

There's nothing worse than ruining a great photo but not nailing the focus correctly. Modern autofocus systems are great, but leaving it to your camera to decide where to focus is not always the best thing to do, especially in poor light when autofocus may struggle.

Modern cameras have a range of tools available to help you nail your focus every time, so spend a few minutes checking your camera manual to see which ones are available, and learn how to use them.

Want to jump-start your learning?

Don't forget that if you want some direct help with your photography, I offer a range of 1-2-1 photography courses for Devon based folks. If you're not nearby then I also  offer residential weekends for beginners or intermediate photographers.