Photo tricks. Part 12. Focus Trap

The focus trap is an interesting feature to catch the desired subject in focus without focusing itself.

Photo tricks. Part 11. Focus Trap

Photo tricks. Part 11. Focus Trap

The focus trap is also called focus trap... The essence of the reception is very simple, the camera focuses at a certain distance, and then waits for something at this distance to come into focus, that is, to fall into the so-called 'trap'.


First, how to configure:

If you have a professional-grade camera, such as Nikon D300, D700, D3s etc., which has a special AF-ON button

1. Set the 'AF activation' function from the 'Autofocus' menu item to 'AF-ON only'. In this position, auto focus is only available when the AF-ON button is pressed, and the shutter button when pressed halfway will activate metering exposurebut will not auto focus. This is the standard focus mode for professional photographers.

2. If using the AF-S focusing mode, set the focus priority in the camera menu using the 'Priority selection' menu item. for dir. AF-S 'to' Focus'. When using focus mode AF-C, then in the camera menu set the focus priority using the 'Select priority. for dir. AF-C 'is also set to' Focus'.

3. Set the focus mode on the lens to the auto focus position. Focus in any way at the desired focusing distance, press the shutter button all the way, and wait until an object appears in the focusing area, as soon as the subject gets into the 'trap', the camera releases the shutter.


If you have an amateur level camera such as Nikon D5100, D60, D80 etc., which does not have a separate AF-ON button

1. Using the camera menu, configure the button AF-L / AE-L to 'AF: AF-ON'. It's good that all Nikon cameras have this button and can always be reprogrammed. After this setup AF-L / AE-L button will simulate the operation of the AF-ON button on older cameras. When you press the AF-L / AE-L button, the camera will automatically focus. Auto focusing by half-pressing the shutter button will not occur.

2. Put the camera in focus mode AF-S or AF-A. Unlike professional cameras, almost all amateur cameras do not have the ability to prioritize focus, in AF-C trigger priority always works, and in AF-S mode, focus priority always works. Features of amateur cameras described here.

3. If the camera has the ability to set the focus priority for AF-S, AF-C modes, for example, such a function is in the amateur camera Nikon D5100, then you need to set the priority 'Focus' for such modes. If you don't want to set priorities, on amateur cameras just turn on the mode AF-A.

4. Set the lens focus mode to auto focus mode. Focus in any way on the desired focusing distance, press the shutter button all the way, and wait until an object appears in the focus area, as soon as the object falls into the trap, the camera releases the shutter.

Attention: Some new Nikon cameras cannot be set to focus trap mode. A reliable list is not known.


The focus trap works in any focus mode: one point at a time, with dynamic focus area selection and normal auto mode. Best to use a trap in single-point focus mode or with dynamic focus area selection.


Where to apply?

The focus trap can be used to easily catch moving objects.

Example: at motorcycle competitions everyone knows where motorcyclists will pass. On a tripod, we focus the camera on the place where we want to catch a motorcyclist. Press the shutter button all the way and wait for the rider to fall into our focus trap. With the usual focusing method, the focusing speed of the lens will not always help to quickly respond to a changing situation. In general, there are many examples.


Conclusions

The focus trap is an interesting way of working with a camera. With the help of the trap effect, you can simplify the shooting of dynamic events, or make manual focusing easier. I advise you to do your own research.

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Material prepared Arkady Shapoval.

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Comments: 262, on the topic: Photo Tricks. Part 12. Focus Trap

  • Amateur

    I figured out the settings. Settings are also available through the f menu.

  • Andrei

    Finally, I succeeded. D-5300: in the menu I turn on AF-C mode, as written by Arkady, I point the camera at the doll, press the AF-L / AE-L button, without releasing it I take the camera aside. the picture in the viewfinder will become cloudy, unsharp (not earlier), press the shutter button and point the camera at the doll - the shutter is triggered. I would like to clarify the picture in the viewfinder must become blurred, only then the shutter will not be triggered immediately.
    PS Once again, thanks to Arkady and kind people who came up with the correct algorithm.

  • Nikita

    Please tell me, I have a D7000 + Helios without dandelion, is it possible to use such a focusing trap? Difficulties just with the item "We transfer the camera to focus mode AF-S or AF-A." :)

    • Arkady Shapoval

      You can not.

  • Don

    I have eight hundred and 5100. It is clear that this is not on the d800, and as I didn’t set up the d5100, according to your description, I didn’t succeed.

    • Alexander Malyaev

      If I am not mistaken, in D800 this defect was fixed by firmware from 13.05.2014/XNUMX/XNUMX and now the trap should work as it should: https://nikoneurope-ru.custhelp.com/app/answers/detail/a_id/60518

      • Don

        Thank you, Alexander. My firmware is updated, I just did a little wrong, but everything works.

    • Sergei

      Today I tested the trap on D5100. It is such a feeling that if an object enters the depth of field, the shutter is immediately triggered. I experimented at 16-85, FR = 85, f / 5.6. Focus - AF-S, focus priority set. I think that with a lens with a higher aperture, the effect will be more successful. But I don't have such a lens. I think it's also advisable to play around with a couple of exposure / ISO. Photographed passing cars on the road. At home I will look at the results on my computer.

      • Sergei

        I looked. Unsatisfactory. In all the shots - blur and defocus, but when shooting the shutter just worked when the car was in the frame at a given place. I'll have to try again with a tighter aperture and a faster shutter speed.

  • Victor

    Nikon D50 everything worked out. The item by which the focus lock button is configured in the menu is called AF-Start.

  • Dmitriy

    Nikon d3300 does not work.

  • Alexey

    D5200 - does not work. Maybe a firmware bug? At 1.02v, there was a fix for the AF-ON mode - sometimes it did not focus when pressing AE-B / AF / B. Focusing now, but what's the point? It hits everything without focusing ... In the AF settings, only AF-C can be assigned the priority of focus or Release (focus priority is selected). In the rest of the settings I tried both AF-A and AF-S - the trap does not work, even if you crack it. Focus area - on the 1st point. Sadness ... or CHYADN? Aiming, focusing (book AE-B / AF-B), with AF-ON pressed, turn the camera (loss of focus), pressing the shutter release and ... the shutter! but there shouldn't be a descent until I point back at the object in the DOF ...

    • Oleg

      +1
      D5300, 18-140. The button is set to AF-ON mode, autofocus works correctly. At the same time, the shutter is pressed without focusing, at full blur.

  • Dmitriy

    Arkady I have a question. The D300 camera and several manual lenses that I successfully use in semi-auto mode (built-in metering and auto ISO solve), the question remains only about focusing, solving the focusing issue in this way would make my life completely honey! So the focus trap on manual glasses will only work if there is a "dandelion"?

    • Arkady Shapoval

      Yes, only with dandelion.

      • Dmitriy

        Thanks for the answer)) Ah Nikon Nikon well, is it really so difficult to finish it to the end! ((As I understand it, the software problem. What do you think?

        • Arkady Shapoval

          Given that the trap function works on Pentax without any dandelions, we can safely say that this is a software flaw in Nikon. And most likely, it's just such an anti-feature to use native autofocus optics.

          • Dmitriy

            Arkady, maybe there are firmware for older Nikon cameras, according to the type of operation of the Pentax trap?

            • Arkady Shapoval

              I have not seen such firmware.

              • Dmitriy

                It may be too deep, but still. Since the topic is very interesting to me, I read the Pentax forums, it is also not so simple there, and in fact the trap works when closing contacts in a bayonet. I didn’t find such information on Nikon, I don’t have any desire to burn the camera using the scientific poke method, maybe you had some kind of information on this method?))

      • Dmitriy

        And yes, including I use Helios 44-2 with the solution of the problem of infinity as described by you on this site, with the stitch of a skirt and putting another on the lens body, I express my great gratitude for the idea!)) The rest of the manual glasses for Nikon mount. It turns out not fate, and using Lushnikov !?

  • Novel

    Can I use the Nikon 5100 Focus Trap without Dandelion Lushnikov ?! otherwise the thoughts from the article do not reach my delitant brain (about the photo)

    • Arkady Shapoval

      You can not.

      • anonym

        Good afternoon, Arkady. Tell me on the Nikon d7000 with the Nikon 50mm f1.8g lens this function will work.

  • Novel

    I re-read it again and realized that I couldn’t do without Lushnikov, tell me the link where you can order or buy it ?!

  • Novel

    tell me where you can buy Dandelion Lushnikova for Nikon please give a link

    • anonym

      Have you been banned in Google?

      • Novel

        I want a verified link, there is no trust in Google, maybe they are asking for a 100% prepayment. half suck on a sucker I think

    • Lynx

      on the official website of Lushnikov.
      and yes, they ask for a 100% prepayment there.

      • Novel

        can you trust them?

        • Lynx

          I bought there

  • Sect®

    d750
    Aperture Priority
    AF-S - Focus Priority
    AF-C - Focus Priority

    AF-ON on the Pv button

    In AF-S mode. I press Pv - it focuses, I remove the camera, I press the shutter - there is no shooting until I bring it to the object where I was focusing

    In AF-C mode. I press Pv - it focuses, I remove the camera, I press the shutter - shooting everything muddy at once :) Ie. in AF-C, focus priority works differently, or rather does not work?

    • Sect®

      Thanks: lesa
      14.11.2014 in 21: 2
      Understood :)

  • Radda

    Thank you, everything worked out for me)

  • Vadim

    There is a manual focus mode, why fence the garden?
    The shutter should be controlled by the photographer and not the camera. And there is also the concept of depth of field.

  • Ruslan

    so what is the essence of the trap ??? If we brought focus! then moved so that the focus is gone in the frame! And then again we turn the camera to the point we need! so at the same time, without waiting for the subject to shoot, the shutter fires because there was focus on this territory! ?? Or is it somehow wrong ??

  • Ruslan

    If anyone has not figured it out yet! On the D80! In the menu, find the function of the submenu AF-L / AE-L enable on AF-ON! then conduct an experiment in which you will understand! Namely ! put a chair in the room on a chair, a book or any object! then move back the chair let it stand in the middle of the room! by pressing the AF-L / AE-L button, focus the camera on the book or whatever you put on the chair!)) then without moving the camera! I have it on a tripod! it is important! remove the book or the item that you put on a chair! then go back to the camera on the tripod! and press and hold the shutter button all the way! it will not click for you, that is, it won’t work! at that moment when you hold down the shutter button! ask someone else to draw a hand along the plane where exactly the book stood or your other object! And the bird will fly)) That is, the shutter release will work! This current feature works with autofocus lenses! Well, as people write with Lushnikov’s dandelion!

  • Ruslan

    Many thanks to the author of this article and find! Yours faithfully!

  • Oleg (Oll)

    For a more comfortable use of the "trap":
    -Tripod.
    -Remote cord - a device that allows you to release the shutter of the camera remotely - connect to the camera.
    - Shooting mode - Continuous low speed or Continuous high speed.
    -Perform the above manipulations with the camera settings for the "trap"
    -Press the shutter release on the Remote cord and turn on hold the shutter button.
    -Camera will wait and shoot whoever gets into "focus" until shutdown (or until the battery runs out).

  • wolffserg

    on the Nikon D7100 focus trap does not work

  • Alexander

    Thank you, Arkady, for the hint that such a function is available, on Nikons, being the owner of Canon 6d, I used Nikon lenses, and this very function implemented by the “ML-focus trap” firmware was irreplaceable for manual focusing. It turns out that Nikon has it all in stock.

  • Julia

    Arkady, please tell me, is it possible to use this method when shooting children in the playground?
    Thank you.

    • Valery A.

      Why not, if you are comfortable? But it seems to me that AF-C (AF-A) mode is easier, I also need to keep the focus point on the object.

  • Julia

    Arkady, tell me, can I set up this trap on the Nikon 7000 camera with a 50mm 1,4D lens?
    The lens itself is not autofocus, but the camera has a “screwdriver” and normal autofocus works without any problems. I would like to learn how to apply this AF technique.
    Thank you.

  • Vyacheslav

    Dear Arkady. I have a Nikon d3200. The trap does not work. Question: Have you personally tried to set up an autofocus trap on this camera? If so, what are the results?

    • Arkady Shapoval

      There is a comment.
      Caution: Some new Nikon cameras cannot be set to focus trap mode.

      • Vyacheslav

        I saw this remark, but I hoped that this did not apply to my camera :-).

        • Alexey

          It works great on the D3100. And it works both with the native nikkor af-s 18-200, and with Sigma 17-70. The complexity of the use is that the flu should be small enough so that the background does not fall into the focus area, seeing that the camera’s focusing system gave out a technically correct, but actually false response. This is immediately visible in the focus confirmation indicator in the absence of the actual subject. When it is possible to choose the right shooting conditions, the trap works like a clock.

  • tatianaput

    Hello. Thank you so much for the article. Finally, something worked out for me. Step by step for those dumb like me, for whom the instructions for the Nikon D7000 are too complicated.
    1. In the AF-S autofocus settings, set the focus priority.
    Accordingly, in AF-C the priority is descent. Switch between AF-S AF-C by
    button on the shift lever AF-M and the middle wheel (shutter speed). If you suddenly need it.
    2. We select a lens with a shallow depth of field (only not wide, it is aimed at everything)
    there was makrik fix 40. We direct him to something on which he, in principle, cannot focus, I
    it was just a white screen, you can, the sky without clouds.
    3. We hold the button on the Live View lever and together the release. Nothing happens. Move the camera
    somewhere. As soon as something sharp hits the focal point, the trigger is triggered. I even have
    2 times, since it’s worth bracketing 2. (I have one focus point in the center, it’s more convenient for me)
    But still there is 1 question. I'm about those same motorcyclists. They do not fly across the sky. So, the camera will be aimed at the road or at the trees, grass. What to do in this case? Guided by hand? And then what? In manual mode, this does not work. Switch to autofocus? So what? Then he will go on the road, or whatever he likes more, and not the fact that he is a motorcyclist.
    Please guys, do not laugh at the blonde.

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