Reframing with the Object Tracker in Motion

so final cut pro and motion now have a new object tracker so you can track objects like this little robot guy maybe to add a title to and you can track faces to add titles or maybe to add color correction to but what if you could use the object tracker to stabilize a shot in other words if i were to move my head left and right but i was able to keep it right in the center of the shot or if i were to tilt it and it would say straight up and down or if i were to move forward and backwards but it would stay the same scale well today on macbreak studio i'm going to show you how you can reframe shots using the object tracker in motion first i want to give credit where credit is due in the ripple live that we did last week on october 21st one of the commenters daniel suzuki mentioned how you can apply the match mood behavior to a camera which of course makes perfect sense so that kind of spurred me to do what we're going to talk about today all right i'm going to show you three different examples of how we can reframe shots with the object tracker in motion now doing so requires extra resolution so you'll see here i have the project selected and you can see that this is a 1920x1080 or hd project and this clip here if i select it you can see it's at 50 size because it's a uhd or 4k clip scaled down to fit in hd so we've got plenty of extra resolution to work with if i play the clip notice the framing there's a little jar at the beginning where i stepped on a coconut or something but you can see as madison walks towards us she shifts off to the right and then drops starts to drop out of the frame so a terrible job by the gimbal operator which was me so it's a nice smooth shot it doesn't really need stabilizing in that respect but the framing is not that great so let's see what we can do to address that in order to reframe a shot with the object tractor the first thing to do is add a camera then i'll switch to 3d and then on that camera under behaviors i'll choose motion tracking match move i'll move my playhead to the beginning not required hold down the option key just like in final cut and it recognizes her face so i'll select that i'm going to turn off rotation because i don't want the whole image rotating everywhere based on her face rotation so i'll turn that off and click analyze and the object tracker works basically exactly the same as it does in final cut pro now to see what's happening i'm going to press command minus to zoom out a little bit i'll select the video clip so we can see its bounding box and if i play now you'll notice how the whole bounding box is moving around in order to keep our face of our subject in exactly the same position and in fact this is kind of cool just to verify that i'm going to create a new group shift command n i'm going to make it a 2d group so it's not affected by the camera and in the library i'm going to add a little arrow to that group i'll point it towards her and let me turn her off first just so you can see that that arrow is not moving at all let's extend it out to last for the whole project by pressing o so that arrow is not moving at all when we turn her back on in play you can see how that arrow just sticks to her face because the object tracker has now kept her in exactly the same location in the overall frame so it's framed everything around her face she's not moving at all which is awesome but obviously we now need to deal with these black edges based on the bouncing around of the framing i will turn off that arrow group now to scale up the video clip we have a couple of options if i select the camera and go to the inspector to properties we could choose to adjust the position in z if i drag on that you'll see it changes effectively the scale of the clip i'll undo that another option is scale z for the camera which does the same thing it's more sensitive i'm going to undo that the problem with adjusting the camera either in position z or scale z is we can't really tell how much we're increasing the scale of the clip and we know we don't want it more than double the current size of the clip so instead i'm going to select the video clip itself and i'll navigate to a point where it's the most off and actually i'll purposely go somewhere else so it's really off there it's moved a lot but let's say i think that's where right about there and i want to increase the scale and now i know i can't go beyond a hundred percent without losing quality so i'll scale it up and right about there it still fits in the frame we're about 70 percent okay so now i still can reframe the shot if i select the camera i can use the x and y parameters notice the little gear icon indicates that these are being driven by the match move behavior but i can still override them and reposition the shot the tricky thing is i can't see the bounding box of the video clip anymore i have to select the video clip but then i can't see the controls for the camera but what you can do is this i'll select the camera and i'll use this little pin at the top to pin these parameters now when i select the video clip we still see the parameters for the camera so now i can see the full bounding box of video clip which helps me when i'm reframing the shot to know how far to go of course i could just see where it turns black but this is a nicer way to go i think let you really see what's happening and then i can scrub through and say let's say over here oh this is no good so i need to reposition it in x to about there and then up there it jumps up too high so i need to come down in y and if i can't get it to work i might need to scale it up a little bit more but now when i scrub through we look good it's a little bit over too far there so i'll move it over in x and then it comes over a little too far there so i'm going to need to scale it up a little bit more now i don't have the parameters for the video clip in the inspector anymore this is for the camera but in the heads-up display i can adjust the video clip scale so i'm going to scale it up a little bit more so that the bounding box moves just outside right there and then as i scrub through we look like we're good so great so now what i'll do is i'll click to deselect that clip so we don't see the bounding box shift z to fill the frame and play it back and now she's fixed in one part of the frame she's not moving at all relative everything else which is cool but at the same time it's a little too much for me i can see we still get a little bit i didn't quite scale it up enough we got up a little bit there so i'll just move the camera down and why a little bit and we should be good there yeah so now she fills the frame the entire time and stays in one point but the result naturally is that the background bounces around a lot in order to keep her steady in the frame so it's great that she's not moving around in the frame anymore she's not dropping low out of the shot towards the end but it's a little too much so here's a great way that you can back off on this impact of this tracking so with the camera selected i'm going to press command a to bring up the keyframe editor and you can see here what the match move is doing to both x and y so the green is position in x and the purple's position in y and you can see how the match move is moving around the frame especially right here in x where she dips down low in the frame so x is moving up to adjust that now it's a little too much so what i'm going to do is for the position of the camera i'm going to click the downward facing arrow and choose add parameter behavior average and look at the lines in the keyframe editor once i select this they immediately smooth out the amount of smoothing is determined by this window size and if i increase it you can see it smooths out more and i decrease it it smooths out less so you can choose an amount that works for you so maybe i'll do something like that play that back notice i'm not getting full frame rate playback if i close the keyframe editor it will improve playback usually not now probably because i'm running my screen recording software but now i still have her much better framing but not quite as extreme as before i've smoothed that out nicely because i've smoothed it out i'll press command minus i can probably scale her down a little bit because we're not adjusting everything as dramatically we have some extra room now so i can scale that shot back down a little bit and still be all within the frame without ever showing any black edges so there what we've done is to match move a camera to her face to keep her in one place and then we've blown up the clip enough to be able to fill the frame and framed her where we wanted and then backed off on the effect with the average behavior one more thing i did is i added a few keyframes for rotation z to fix that stumble where i kind of slipped going backwards right here in order to straighten out the shot at the very beginning and here's how they look side by side [Music] in this shot we have a kayaker working their way down the river and notice how they move up in the shot the framing is staying pretty steady for the overall scene but the kayak is moving in the shot but let's say we want to keep the kayaker at the same place in the frame once again i'll add a camera switch to 3d add the motion tracking match move behavior to the camera i'll put it over the kayaker and as opposed to final cut you can't drag a corner of this bounding box to scale it all at the same time you have to do these separately and make it very small and i don't care about rotation here i'm just going to analyze for position by the way it analyzes for position scale and rotation those just aren't turned on right now you can always turn them on after the fact and the other thing i want to mention is this is a very smooth shot if it were jerky you could always stabilize a shot before using the object tracker under behaviors under motion tracking you could use the stabilized behavior which works the same as it does in final cut pro now that that's analyzed i'll hit command minus to zoom out a little bit and select the clip so we can see the bounding box and once again we can see the motion of the clip as the match move keeps the kayaker at the same place in the frame i'll leave my mouse here without moving the mouse and you can see how it's tracking that kayaker perfectly because we're keeping him in the bottom of the frame him or her so now what i want to do obviously is scale this up so that it will fit in the full frame this particular clip is not a uhd clip so this is more just for demonstration purposes so i'll increase the scale of the clip and i'll reposition the camera once again i'll pin the controls to the camera and select clip so we can get a better idea of how much extra room we have to work with and i'll move this up in the shot and we'll see if that's too much we go to the beginning and it's definitely too much so i'll move it down and this is a case where we will need to scale it up quite a bit to get it to where we want it to be i'll keep scaling it up and adjusting it in y at the beginning of the shot and then seeing where we need to go by the end it needs a little bit more and we can go a little bit higher and really to get to the end of the shot we need to scale it up even a little bit more at the beginning pull it up as far as we can and now it stays completely in the shot the whole time i'll deselect everything shift z to fit the full frame and we'll play it back and kind of similar to the other one it's a little too much there's a little bit of jerkiness going on here so let's select the camera command 8 so we can see the basically the path of these corrections for both position x and y and for the camera's position i'll once again add the average parameter behavior i think the default value of 10 often does a really good job and now with that on i'll play it back and it plays quite a bit more smoothly while still keeping the kayaker at the bottom of the shot and let's look at how these look side by side if you're enjoying this content click the subscribe button below in this third and final example i'm going to show you how to work with scale with the object tracker and i'm going to debunk the very popular myth that focal length has an impact on the distortion of objects so i'm using myself so i don't distort somebody else's face so i have a simple shot of me walking towards the camera obviously the camera is at a fixed focal length i believe it's 24 millimeters here so i'm walking towards the camera and what i want to do is have my face keep the same scale the whole time so as usual what i'll do is add a camera this time i'll use the keyboard shortcut option command c return to switch to 3d then i'll choose behaviors motion tracking match move drag it over my face hold the option key down so it recognizes my face and i'll click analyze and now i'll command minus to zoom out a little bit select the video clip so we can see the frame and you can see what's happening and now my face is locked down in the center of the frame as i get closer but scales not being affected and you might think oh i just got to turn it on i'll select match move and turn on scale but you'll notice nothing happens i'm also going to turn off rotation it will just make the scaling we eventually do a little bit easier so here's the problem it is tracking scale but it doesn't know how to apply that scale to the camera so if i select the camera we go to the properties inspector you can see that position z is now being modified by that parameter behavior by the gear icon and scale is being affected for x and y but not z and in a camera the only thing that makes sense is scale of z so if i weren't match moving a camera if i were match moving an object like a shape or something else it would scale but the camera can't because it needs to be z so what we can do is link the scale of z to x or y notice that x and y are different values so the object tracker is tracking the scale of my face non-proportionally it's not a proportional x and y are different so we need to choose one so what we're going to do i'll select the camera and then for scale z i'll choose add parameter behavior link i'm going to link the scale z to the camera and i'll link it to properties transform scale and i can choose x or y i'm just going to choose y here i often find y works a little bit better now that i've done that and i play back notice that my face stays the same size and the whole image shrinks down to accommodate it because it's keeping my face the exact same size the whole time which is kind of super cool now obviously to scale this up is going to require much more resolution than just doubling and again have a uhd clip and an hd timeline but i'm going to have to zoom this up quite a bit but this is just to demonstrate a point here so you can see how you can link the scale to make that work and now i'm going to increase the scale this clip to fill the frame and i'll go down a little bit more because i notice i can move it over so i'll select the camera once again i'll pin the camera controls and select the frame just so i can see what i'm doing and i can move over an x like that and i can also move over and why but i'm not going to move over and why and i'll show you why if i go to the beginning now i can move over and y i'll move up a little bit to reframe me myself at the beginning and maybe over this way a little bit and then towards the end i'm still a little bit low in the shot and the reason for that is the scaling of the camera is around the camera's anchor point which is in the center and this my anchor point of my mug here was in the center of my face so they're not the same and the way that we can deal with that is by simply adding a move behavior to adjust for that so what i'll do is choose uh select the camera behaviors basic motion move and then at the very end of this you can already see i'm now framed up nicely it just did it automatically it sometimes just works it shouldn't but it did so that works now obviously for this to work i am zoomed in very close here you can see all the noise in the shot because i'm blown up a massive amount here uh to get this shot so it's a little bit you know it's obviously not a useful shot but it does demonstrate how you can use scale you usually wouldn't use it on something go extreme but let me show you notice how my face looks kind of flat there and when it gets closer to the camera looks very distorted so guess what like if you go and search from the internet for focal length on face uh focal length effect on face you'll see that it'll tell you that the focal length will affect a face and in fact sometimes you might see this gif of different focal lengths seeming to have an impact on the face but the focal length has nothing to do with it at all it's all based on how far you are from the camera so this is a fixed focal length where i'm far from the camera so my face looks flatter here and here i'm closer to the camera so it looks more my nose really sticks out put it that way uh sorry you have to look at that but um that's the deal it has nothing to do with focal length it's all about the distance from the camera so really what we've done is create a little dolly zoom effect in post usually a dolly zoom effect is created while you're shooting by moving both the camera and changing the focal length at the same time to keep the object in the frame the same size if you think of the jaws shot or in vertigo here we've done it in post by using the object tracker to reframe the shot using scale and here's those two shots side by side so we'd love to hear your comments below please subscribe and we'll see you next time here on macbreak studio [Music]

Channel: Ripple Training

Views: 9,087

Keywords: Ripple Training, Steve Martin, Tutorial, Apple, Digital Barn, How To, Help, Video, Film, Editing, Learn, Example

Id: c3SufAk-BWw

Length: 20min 11sec (1211 seconds)

Published: Sun Oct 31 2021