Trap focusing requires the photographer keep the shutter pressed (point#6 below) until the object appears at the point where camera is pre-focusing.

  1. Set custom setting #A5 to AF-ON ONLY
  2. Set the focus mode to SINGLE SERVO
  3. Set Auto focus area mode to SINGLE POINT (9 point, 21 point, 51 point or 51 point 3-D will all work)
  4. If your lens has an A/M switch, make sure it is set to A for autofocus mode.
  5. Pre-focus the lens for a particular distance. Don't forget that a more convenient way to use this trick is to pre-focus using not the shutter button, but the FOCUS button on the back of the camera can be used. I find this easier and more effective.
  6. Press and hold the shutter release ALL the way down, the camera shoots only when the selected focus bracket is in focus.

I wonder if forcefully pressing the shutter ALL the way down can damage the shutter release. How much pressure should I apply? Though I know I am sounding dumb, but I want to be sure before I get the new piece broken out of my sheer stupidity.


No, there's no problem. The instructions aren't telling you to force anything. Rather, most modern shutter release buttons actually have two settings — a light press (or half-press) and full. The half-press usually activates focus and possibly exposure calculations.

I don't know of any cameras with an actual physical mechanism to resist a full press, so you need not worry about breaking the shutter button by pressing it all the way. Instead, if they're in a focus priority mode (as opposed to release priority), they'll just ignore that full press. Or in this case, will allow it, but nothing will happen until focus is achieved.


Just apply the same amount of pressure you normally would when fully pressing the shutter button to take a picture. The camera will detect that the shutter button is pressed all of the way down, but it won't actually take the photo until it has confirmed proper focus at the point you indicated. Since the shutter button on your camera is an electronic switch and not a mechanical release you don't need to worry about trying to force the shutter button all the way down while the camera is "refusing" to release the shutter.


No, because cameras are electronic today. The shutter button is just a simple electrical switch. It signals the computer chip in the camera when it is being pressed. It does not need much pressure, it's a simple switch that does the same thing either way. The computer will not activate the shutter mechanism until it sees that focus has been achieved (the green dot in lower left of viewfinder), so there is no effect at all on the shutter until that time, when it is just routinely activated, same as any other time.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.