5 Replies Latest reply on Oct 10, 2016 9:30 AM by Roei Tzoref

    how to match 2 tracking points?

    Reiner_M Level 1

      Hello,

       

      how can I match the tracking points of two different objects. I would like to match to movements.

       

      (Basically I have 2 slow traveling shots along a window, each with different illumination. I would like to match the two windows...)

       

      Thanks in advance,
      René

        • 1. Re: how to match 2 tracking points?
          Roei Tzoref Adobe Community Professional

          not sure exactly what you mean by "matching the movement" as obviously an object movement is inherent by the object/camera move that was caught on tape and cannot match to another object unless a careful compositing is performed on the shot.

           

          stating what could be also obvious - if you have 2 objects in your shot that you want to track then:

          1. if it's 2d tracking (Track Motion) you can track each separately and use each tracker for each object. (create a null from the tracker and attach the object to it)

          2. if it's 3d tracker (Track Camera) then you will have many cross points to choose from and if there is one approximately where you need your object to be, you can create a camera and null and place the object in the nulls position.

           

          if you need something else maybe you should specify exactly what you are dealing with (screenshots and video are most welcome)

          • 2. Re: how to match 2 tracking points?
            Reiner_M Level 1

            thanx Roei,

             

            sorry for my bad explanation.

            I think you describe it more or less in the 1. example (2d).

             

            I would like to track an Object in the first shot.

            Then I want to track an Object in the second shot and make that tracked object move along the path of the first Object.

             

            To hopefully explane a bit better my example:

            the first shot is a travel passing a window (it was shot inside a room and therefore the window is overexposed).

            the second shot is the same travel passing the same window, but with lower exposure to expose correctly the window....

             

            I have masked out the second window and want to put it on top of the overexposed window from the first shot.

            The two shots are very slow and with tripod, but were made by hand and therefore they are not totally in sync. I would have to adjust the position slightly frame by frame. Thats why I thought of tracking a corner of the window of each shot and then make them align in position.

             

            bright shot.jpgdark shot.jpgdesired composition.jpg

            • 3. Re: how to match 2 tracking points?
              Roei Tzoref Adobe Community Professional

              this is how I would try to pull this off: basically you stabilize the motion, adjust the window and layers handles to match exactly in Shot A over Shot B by adjusting keyframes manually for the position property and Time remapping, then re-introduce the motion

               

              Shot A - the masked underexposed

              Shot B - the overexposed

               

              1. place Shot A above Shot B. trim only the necessary duration and place as accurately as you can

              2. stabilize motion in Shot A and apply to the layer

              3. stabilize motion in Shot B  and apply to the layer

              4. use the difference mode to place the layers exactly one above the other.

               

              now you have a comp with both shot's stabilized and the window is accurately in the same place.

               

              5. create a solid above shot A and set it as an alpha matte - the mask for your window.

              6. for Shot A set a keyframe for position and time remapping at the start frame. make sure the window is exactly in the same position, and that the layer handles are exactly on top of each other.

              7. go to the end of the shot and align the window again and set a keyframe for TR an Position

              8. carefully examine the shot through and make additional keyframes as necessary. the few the better.

              in the end it should look like something like this:

              9. re-introduce the motion by attaching both shots to a null with the tracking data of the Shot B (you already have the tracking data, just change the track type to transform and apply it to a null)

               

              you could probably get a way without steps 6-8 if there wasn't any parallax shift.

              • 4. Re: how to match 2 tracking points?
                Reiner_M Level 1

                Hi Roei,

                 

                couldn't try it out earlier, but just did. It worked.

                 

                Thanks a lot for the good idea!

                 

                Best, René

                • 5. Re: how to match 2 tracking points?
                  Roei Tzoref Adobe Community Professional

                  Great! Post it if you can