If applicable on your camera model, also make sure that the shutter priority for AF.S is set to “Focus priority” (custom menu item #15 or #17 on many cameras, called “AF.S Setting” and enabled by default).
Once this is done, a manual lens needs to be mounted on the camera.
Alternatively, you can use an autofocus lens with an AF/MF switch. The switch should be set to MF.
If your AF lens doesn’t have such a switch, the camera can also be tricked into thinking that a manual lens is mounted by depressing the lens lock button or even taping over the electrical contacts, though this is far from recommended!
Users who have set the AF to trigger only via the rear AF button will not be able to use catch-in focus unless they also allow AF via the shutter button.
Using Catch-in-Focus
Just a few easy steps will let you take pictures using catch-in focus.
Set your camera to AF mode
- Set the camera to AF.S (set via the AF switch or the menu, depending on your body)
- Select the AF point(s) you’d like to use*
- Focus at your desired distance
- Fully press and hold the shutter button, and wait for your subject to come in focus. When it does, the camera will automatically take the picture**
