Focus is quite possibly one of the most vague and mysterious things I’ve ever had to suss out in my photographic journey. It got ever-clearer (pun intended) when I got my Canon 7D. Even now, just admitting that I have one makes my heart skip a little beat. Ok…reeling in my inner geek. Let me tell you about the focus points available on the 7D. Many of them are available on other Canon models so just have a browse through your manual and your settings to see what you’ve got but the concepts remain largely the same.
Spot Auto Focus. This is a totally new feature available on the 7D. With this mode, you choose the focus point for pin point precision. This setting is much like the one I will explain next, but as you can see, there’s a focus point within the focus point on the screen display. This is the most precise option and excellent for macro photography, the top of a newborn’s head or the ‘ring shot’ at a wedding. Although this gives you the ability to focus on a very tiny and precise area of the scene, it is not good for moving subjects because the area of focus is just so small.
Single point Auto Focus. Although this is the second option on your screen, it is probably the most widely understood mode by EOS users. You just move the square where you want your image to be focused. You can get precise and accurate focus, although you don’t have to be as concerned about some movement in your subject. As with any of these modes, you can move your focus point while looking through the viewfinder. Just press the AF point button with your thumb (the little round button, furthest to the right on the back of the 7D) and move the wheel to change your focus point. This allows you to continuously control your point of focus without losing momentum in your session.
Auto Focus Point Expansion. I totally love this mode. It’s my go-to focus mode. Although AF point expansion isn’t new to the 7D, it’s the first time it’s been available in a mid-range camera. Before now, it’s been available on cameras like the 1D (you know the one…costs, like, four grand?) What AF expansion does is allow you to choose a focus point (the middle) and the immediate surrounding points become active. This means if you’ve focusing on something that moves, the surrounding points will quickly pick up the slack and grab focus so focus is not lost. Which means that you can even track a moving subject in AI Servo and maintain the exact area of focus you decide.
Zone Auto Focus. Zone AF is another totally new feature for the 7D (or any EOS for that matter!) Simply put, it’s like using single point AF but you can choose a cluster instead of just one point. The camera will focus on whatever is closest in the zone you have chosen so watch your focus. When using any of these modes, I have turned on the option (in my setting menu) of having the camera display with a red square the point of focus on each image as I look at them on my camera’s screen. Then I will know if I need to reshoot the image for the focus I planned. The only draw back to this mode, in my opinion, is that there are only 5 pre-set zones (center, far left, far right, top, bottom) so you can’t just move the zone over by one point like you can the AF expansion mode. But then, I suppose that’s what we have feet for!
19 point AF. This is the fully auto focusing mode. Although available in manual, this is also the mode your camera would use if you set it on the full auto. The 7D has 19 available focus points and in this mode, you’ll see all of the little squares bouncing around in your viewfinder as they continually re-set to whatever your camera thinks is the main focus of the image you have composed. I see so many problems with this, greatest of all the complete loss of control. That said, I have found the 7D extremely adept at making this decision, although all the brain power it’s putting into focusing makes getting the shot take a few seconds longer than I’d like.
You can set everything beautifully in your manual mode, but if you image isn’t focused on the subject, what’s the point? It’s for this reason that I believe mastering your camera’s focus system is one of the first things you should set out to learn when you pick up your camera for the first time.