Road to Sharp Images - Understanding Focus Area Modes & Focus Points

Every DSLR camera is equipped with focus points. Focus points help the camera detect contrast, which (to make a long story short), help the camera focus on a scene more accurately. Some of these are regular vertical AF sensor points and some come with a newer cross-type technology. The cross-type sensors detect contrast vertically and horizontally, which means that the more cross-type AF sensors your camera has, the more efficient your Autofocus will be. It's also helpful to know that the more AF points your camera has, the better focusing results you'll get with moving subjects. 

AF-Area Modes

On my Nikon D7000, I change this setting by pressing this button and scrolling my front wheel dial. 

On an entry-level Canon DSLR, you might change this setting by pressing this button and then selecting your Focus Area Mode. If you're unsure about your camera, check your camera's manual. 

Single-Point AF-Area 

Known as Single Point (Nikon) or Manual AF Point (Canon), this mode uses one focus point (one specific area) that you choose to focus on your subject. This mode is great for precision. It's as simple as that. Here's what it looks like when you do Manual point selection on a Canon screen; only one focus point is activated.

Dynamic AF-Area 

Known as Dynamic (Nikon) or AF Point Expansion (Canon) mode, you first choose the single focus point; once focus is achieved on that area, you can pan (or follow) your subject, trying to keep it close to the focus point. Your camera will then try and help you track the focus, by using the surrounding points. This mode works really well for moving subjects. You can also choose how many focus points you want to use; every camera is different and has a different number of these points. If you want to track a small area of the scene, you can choose a smaller number of focus points. If you want to track a subject using the whole viewfinder, you should pick the highest number of tracking points. See my example below.  

3D-Tracking Mode

Some DSLRs have a 3D-Tracking Mode, where you pick the focus point and your camera will automatically activate as many focus points as needed to have an efficient way of tracking your moving subject. It uses a color-recognition technology so you can recompose, while it tracks, for instance, a red car driving down the street or a white bird flying around birds that might be black. The difference between 3D and Dynamic Mode is that you choose the area you want to focus in Dynamic Mode. 

Here's an example of what the different Focus Modes look like on a Nikon (image source from Nikon).

It can be a little confusing to remember how our Focus Modes and Focus Area Modes work. Hopefully these posts help you understand how your Autofocus system works a little better. Try some of these different settings and see which Focus Area Modes work best for you, your subject matter and your camera!

---

Road to Sharp Images - Understanding Your Focus Modes

This first post is going to be part of a series where I will teach you how to get tack-sharp images. There are many helpful tips, but before we dive straight into it we need to understand our focusing modes. I am going to cover the four basic focus modes that come with a Nikon and Canon camera. To find out how to change these modes, please check out and review my video walk through about camera settings, or read your camera's manual. 

Single Shot Mode

This mode is known as One-Shot AF (for Canon) or AF-S (for Nikon). This focus mode is used for objects that are mostly stationary, or to gain control of your single focus point. It is also used for selecting the focus (by pressing your shutter release button down half way) and will allow you to recompose your image. I shoot in this mode 95% of the time and I find that it allows me to have the most control over what is in focus in my image. I love it.

My Nikon viewfinder looks something like this below, one box will outline in red and I can move my selected focus point using the arrows on the back right of my camera (the same arrows used to scroll through your image playback). 

This is what a Canon viewfinder might look like. 

I find Single Shot focus mode very helpful when I'm shooting with a shallow depth of field. 

Active or Continuous Focus Mode

On a Canon camera, this setting is known as Al-Servo and on a Nikon it is known as AF-C. This setting will continuously track your focus point and readjusts as a subject moves across the frame. Simply press your shutter half way to focus on your subject, and when it moves, it will track your subject until you are ready to snap the photo. It's not fail proof, but the camera activates the focusing points and works to keep focusing on a moving subject. I like using this for sports.

Auto Focus Mode

The auto focus mode on a Canon is called Al-Focus AF and on a Nikon it is AF-A. This setting will allow your camera to choose the focus mode, based on what it sees (whether a subject is stationary or moving). It sort of combines the Single-Shot and Continuous modes. Your camera will usually focus on what is predominately filling your viewfinder, or it will focus on the subject that is closest to you. It's best to only leave it on this mode if it is obvious what your subject is, and the surroundings are not very distracting.

Manual Focus

Sometimes if your scene doesn't have enough contrast, or if it is getting dark, you'll hear your camera searching to grab focus. If it's struggling to lock focus, you can switch to manual focus and use the ring on your lens to manually select the focus. It's important to check the dial on your lens to be sure that it doesn't get bumped to manual focus, unless you are intentionally wanting to focus manually. Once it a while I'll accidentally hit this and wonder why my images are blurry. Your autofocus modes won't work correctly if this switch is on manual! 

Hopefully your AF Modes make more sense to you now; these modes dictate how your lens will focus. On Thursday, we'll cover the AF Area Modes which tells your camera where it will focus! 

---