TechniqueLesson 2 of 8 · 20 min · 5 reading, 15 doing
The short version
Press the shutter button halfway and hold it. The camera focuses and measures the light. Then press the rest of the way, and the photo is taken the instant you do.
The shutter button has two stops. Most beginners don't know about the first one. They stab the button in one go and wonder why the photo was taken a moment late, or focused on the wrong thing.
The two stops. The amber dot on each gauge shows how far the button is pressed. All the slow work happens at stage 2, before the moment arrives.
Why the one-stab press fails
When you press straight through, the camera has to do everything in a fraction of a second: find focus, measure the light, then open the shutter. Each step takes a moment. The delay between pressing and the photo being taken is called shutter lag, and it is why the smile has gone by the time the picture appears. In low light the camera may also give up on focus halfway and take a soft photo.
Half-pressing moves all that slow work to before the moment. When the moment comes, the camera only has to open the shutter.
How to find the halfway point
Rest your fingertip on the button and press gently. You'll feel a slight resistance about halfway down. Stop there. Your camera tells you it has focused in one or more of these ways:
A box or boxes on the screen turn green, or another bright colour.
A beep, if the focus beep is on (Module 1 suggested turning it off; leave it on for this lesson if it helps).
A dot lights up in the viewfinder of many DSLRs.
If the box flashes, turns red or keeps searching, the camera can't find focus. Usually it's pointed at something plain, like a clear sky or a white wall. Move the point onto something with an edge or texture and try again.
1
1 The shutter button, here inside the on/off switch. Rest your fingertip on it rather than hovering above.
The fingertip stays on the button between photos, ready to half-press.
Camera up, finger in place. Half-press as soon as the subject is in the frame.
The rhythm: press, hold, wait, press
Half-press as soon as your subject is in the frame. Keep holding. Wait for the moment: the laugh, the bird turning its head, the gap in the traffic. Then press the rest of the way. If the scene changes a lot while you wait, lift your finger and half-press again.
This also works for things that are about to happen. Half-press on the spot where the cyclist will be, hold, and press fully as they arrive.
Focus, then move the camera
Half-pressing also lets you focus on something that isn't in the middle. Put the centre of the frame on your subject, half-press, and keep holding. Now move the camera to frame the photo the way you want, and press fully. This is called focus and recompose.
It works when the camera holds focus while you hold the button, which most cameras do for still subjects. If the focus box follows things around while you hold, the camera is in a continuous focus mode and will refocus on whatever is now in the middle. Module 11 explains focus modes. For now, if your subject keeps coming out soft after you recompose, use Lesson 3 instead: move the focus point to the subject.
On a phone
A phone's on-screen button has no halfway stop. Instead, tap the screen on your subject to focus there. On iPhone and many Android phones, tapping and holding for a second locks focus and brightness (you'll see a label such as AE/AF LOCK). Then press the shutter button. Many modern phones keep recording frames before you press, so shutter lag is short, but the tap still decides what's sharp.
Watch out for
Pressing hard enough to jerk the camera. The full press is a squeeze, as Module 2 showed.
Letting go between the half-press and the full press. The camera starts again from scratch.
Half-pressing on a plain sky or wall. There's nothing for the camera to grip; aim at an edge.
Quick checkYou half-press on a friend's face, hold, recompose, and press. The background is sharp but the face is soft. What's the likely cause?
The camera kept focusing while you moved it, so it refocused on the background now in the middle. Either your camera is in a continuous focus mode, or you let go and pressed again. Move the focus point to the face instead (Lesson 3).
Tip
Some cameras take a photo as soon as you tap the touchscreen. If yours fires when you only meant to choose a focus point, look for a "touch shutter" setting and turn it off.
Try it now · 15 minutes
Set P. Point the camera at a book on a shelf. Half-press, feel the stop, and watch or listen for the focus signal. Let go. Repeat ten times until you can find the halfway point without thinking.
Point at a blank wall and half-press. Notice the camera struggle. Then aim at the edge of a picture frame and try again.
Ask someone to clap at a random moment, or start a countdown timer on your phone and shoot when it ends. Take one photo by stabbing the button when you hear it, and one by half-pressing first and pressing fully on the clap (or the timer).
Put a cup at the left edge of the frame. Focus with the centre on the cup, hold, recompose, press. Zoom in on the photo: is the cup sharp?
Phone users: do steps 2 and 4 by tapping, then tapping and holding to lock.
