Webinar: Tracking Screens with mocha

hello this is Martin Brennan product manager of imaginet systems and we're going to go through a webinar today for tracking screens with mocha so the topics we're going to discuss today are a quick planar tracking crash course so we're going to just go quickly through how mocha does what it does for those that aren't too familiar with the mocha process then we're going to go straight into some complicated screens of various types so first we're going to cover screens that go off-screen and by this we mean not just screens that disappear off the edge of your frame but also screens that get completely covered by other objects such as actors we're also going to go through tracking with very little information so when there's not enough texture detail in the shot and we're also going to be using adjust track for a few cases one for checking for drift and the other four corners that you cannot see because they're covered by other objects well then cover some shiny gadgets in this case we're going to go over an iPad reflection and then I'm going to show you a couple of proteins to lens distortion and show that workflow in After Effects now most of the things today we're going through going to be covered both in After Effects and mocha Pro with one section we're going to go talk about briefly about rendering but these all of these techniques I'm going to show you know mocha Pro 3.2.1 and I'll let you know when and where you can use particular applications with each technique so why the webinar so screen replacement is very common it's one of the most common visual effects things to do in the industry because there are so many screens in modern-day films and feature films for that matter if you just look at a film say for example Iron Man for example the amount of screens that go on there is quite incredible also we've got screens are easy until you do them and this is the case where normally when you look at the screen you can say that's pretty easy to track it's nice big rectangle there's a lot of detail there I can destroy a shape around it and I'm done often that is not the case there's reflections to deal with its obstructions screens don't generally have a lot of texture on them so they can be a little bit harder to track and there's lots of different little cases like that screens are also mochas bread and butter we started out with Monay Monay was a fantastic tool that was used specifically back in our earlier days to track in 4-point corner pins and that's evolved into mocha AES and mocha pros tracking tools with the surface to really get insolent and sell them in shots so it's a great webinar to show you what mochas core tracking abilities are and where they're used and of course there are many many ways to track screens so I'm going to go through now and start I'll stop rabbiting on and we'll get straight into mocha okay so over in mocha I'm going to load our first project and we'll create an output directory so this is a nice basic one to start with just to sort of ease you in we've got a screen up here in the top right corner this is some footage from wanderlust with a level 256 thank you very much for that and we need to track this shot here we've got a bit of smoke floating in the floor ground here we've got a sort of a bit of blur motion blur and focal blur going on and we're just going to use mocha to track this screen getting past all of those details changes so first of all we want to look at the screen itself we've got a big reflection of the trees in the TV here so if I just scrub through that timeline we can see there's that reflection and I say we've got this instruction here which is a little bit of smoke and mochas going to pretty much ignore that because it's going to lock on to texture very very well so I'm going to draw some shapes now just to start this tracking process so I'm going to draw it and explain here and you'll notice here that I am drawing a shape that is not around the television the reason for this is that one the television is pretty much straight black and also it's got a reflection on it and reflections really are a separate plane within the surface so moko will actually try and track that reflection rather than the actual thing you're trying to track so what we want to do is use markers ability to track other areas of the plains and then apply that planner tracking data to the area we actually want to work with so I've just drawn a simple four point X spline here and we turn on the map we can see that area and if I just turn off my Paint Bucket for a second we can just see that whole area of detail that maker is going to track now you'll notice here too that we've got this cocktail shaker in the foreground now this cocktail shaker is not actually on the same plane as these speakers and you know games and brick but it's not actually providing any parallax in this plane either so we can kind of cheat and use it as part of our planar surface to get a little bit more detail you can also see I'm sort of being a bit rough I'm not actually getting right inside the plane I'm actually getting a bit of the background as well and that actually helps maker to work out how this plane is moving now because we do have extra detail however I am actually going to add a little bit more here first of all I'm going to bring this shape right down to the edge as if we scrub our timeline we can see it comes down quite low so I want to get as much detail as possible and I'm also going to use the add shape to spline tool and draw on the other side of the plane here again all of this wall is on the same plane so I can use every detail possible so maker is great at doing this kind of stuff where you can add additional shapes move them around and then track all on that one plane so I'm going to turn on the surface now which is probably the most important thing you want to work with when dealing with screens in mocha the surface is the representation not just of the track but also our 4-point corner pin when we export out tomorrow applications so I'm just going to turn off my layers for a second and I'm just going to line it up on this a vision to begin with now you can line up this surface at any point during the track or when the track is finished but I like to line it up to begin with just so that I have a static point so I can see how my track is going so I'm just going to line that up with the bottom of the TV there and we'll just bring this down and make sure that's lining up correctly it's not quite there let's pull that there and then I'm just going to push that surface up just a little bit so once I've got a surface in place I can either choose to insert a sort of demo clip to see how that's looking or I can just use the grid to see how the track is going so I'm just going to turn off that grid for now let's just go back to none you can also import your own in the insert clip and we'll get onto that in a little while so now that we've got our surface and our grid set up I'm just going to turn those layers back on so I can see them and we're going to quickly look at the parameters down here in the bottom we've got our input channels and I'm going to keep this at luminous luminous basically converts the whole thing to black and white and it basically tries to find the contrast in that luminance what Auto channel will do is try and find the best detail in either our G or B channels and usually you want to keep it on luminance and if you're finding limits isn't working for you try Auto Channel instead the next value here is the minimum percentage of pixels and we want to keep that value quite high so I'm going to set that to 90 think of the minimum percentage of pixels used as accuracy versus speed so the higher this value the more accurate but the slower the track would be the lower it is the less accurate will be and the faster it will be so this all depends on the size of your footage the size are the shapes and the kind of tracking you're doing so I generally aim for about 90 in most of my shots and you're going to see that in pretty much all the shots I do today so we're going to turn on perspective because we do have some little bit of perspective shift in this shot and everything else I'm going to leave alone most of the time you don't ever have to touch the controls in the right side of this panel we could go through the manual tracking section here but today for screens going to not talk about this section here so let's start tracking this shot I'm going to call this one screen track and we can start tracking forwards so now Mako is going through and analyzing this shot I can turn off my mats just to see the whole scene a little bit and we can see that's locking on very very nicely and as this goes up you can see why I've added as much shape as possible because we're losing a lot of this information as it goes out of the screen but we're still looking on very nicely even when this blur happens across the shot so once we've got our blur and our full track done we can go ahead and insert something so I'm just going to import a logo here let's go to our inserts I'm going to choose the mocha logo just for a little bit of shameless promotion and then we can see how that shot is looking and we can see a little bit of drift happening here so this is the first time I'm going to show you a little bit of how the adjust tracked module works so even though we've had a pretty decent track I now need to use the adjust tracked module just to fix a little bit of a problem over here so I'm going to scrub back through the timeline and we'll just see where that starts to go wrong we can start to see a little bit of drift happening here so I'm going to just readjust my screen a little bit just to make sure that looks even and when we get to about here we can start to see that drift so I'm going to stop here and I'm going to move over to the adjust rack module now when you move over to the adjust direct module it sets a master keyframe and this may not be where you want it so you can either choose to set the master at a different section and then reset but in this case I'm just going to set master all for all four corners of my surface so the adjust rect module works by adding another layer of information above the existing track this means that we can fix drift by adding tweening keyframes on the timeline so when I start to scrub through you can see that when I start to move the master keyframe stays up in the top left corner and then the current frame sits on my bottom view just here so it's kind of hard to see what's going on on this screen so I'm going to use a reference point to help me out so I'm going to generate a new reference point going forwards and I'm going to push this down and just find that little corner here on the brick I'm also going to do the same for the bottom corner so we're just going to find an area over here this one will do nicely here so you can see down here we've got the four corners in the adjust track representing the four corners in the surface so when I click these it will jump automatically to those corners in the view this is handy if you're in close and you need to work without having to zoom out and see what the surface is doing so I'm going to first work with that bottom corner and we'll just select that reference point and I'm just going to scrub forwards and see what it's doing and that's holding on actually pretty well so we can leave that one alone we can see even with the focal blur it's still pretty much in the same spot I may just use the pixel nudges this up-down left-right to nudge it down just a little bit but overall that's actually locked on pretty well what I'm concerned about is this bottom right corner so I'm going to click the bottom-right corner of the surface tool inside the adjust treat module I'm going to drag to the end and you can see here that it's drifted slightly over to there right so I'm going to just use again the left tool here to just nudge that back to where it's supposed to be so now when we scrub through we're actually getting a much more realistic movement on that screen so that's one way to use the address rect tool when you need to sort of adjust those areas and now I'm going to go through a different shot where we talked about how to track when you've got a completely obstructed view of your screen so let's move on to that version okay so here we have our second shot and has been generously provided to us by Freddie Wong from rocket jump and this is from video game high school Susan do so I'm going to want to track this screen in the background here but we have a massive problem in that someone walks right in front of it so obviously we need to rotate out the character but that still doesn't help the fact that we can't see the screen anymore so how do we track this well like the previous example we have a plethora of information behind the screen to work with but this time it's not quite on the same plane so to deal with this what we need to do is track the background and then adjust for any drift that's in the shot but this drift will be quite subtle because if we just look and zoom in quite close here you can see if we will look at this corner on top of the postcard here we don't actually have a lot of parallax going on so we'll be able to get away with quite a bit without having to do any adjusting so I'm just going to zoom back out and we're going to start with the beginning of the shot they say starting at the beginning is always a good place to start so I'm going to draw a large shape on screen and I'm going to avoid the screen again just going to grab a little bit of it around here and we've got all of this texture information to work with here it's going to check the brightness there and that's actually looking pretty good so I'm going to track this area and I'm going to do the same again I'm going to turn on my surface and I'm going to bring it down onto the screen to line it up so I'll turn back on that brightness and brighten it up a little bit so we can see what we're doing then I'm going to zoom in here so we can see that surface and use the again that top left-hand corner zoom window to help line up the edges of this screen now it gets a bit tricky down here because we've got an obscured corner covered by this pamphlet down the bottom and an obscured corner with the can over here so what I'm going to have to do is use the edges of my screen to kind of guess where those final edges are so I'm going to come right down to the bottom and that looks about right so just push this up just a little bit make sure we're right on those edges and that looks about right so I'm just going to zoom out again and then we can start doing our tracks I'm going to turn off the brightness there and we're going to turn on about 90 percent pixels and perspective again and start tracking forwards so as he comes into the shot we're going to have to manipulate our shape as we track so he'll come into here and as soon as his red hat starts to hit this part of the shape we're going to have to start manipulating our shape to avoid him the other way we could do this of course would be to actually mask him out completely and then just do a big track but I'm going to show you one method of doing it this way where we move the shape to avoid the obstructions so as he comes forwards it's about to hit so I'm just going to stop the track there and I'm just going to start moving the shape around so we're just going to manipulate that a little bit don't want to manipulate my surface just this one I'm just going to tell that spline for a second then just move this down and move it across and keep on tracking so as he comes across here again his hat is going to come here so I'm just going to nudge that forward a frame and then again we need to move the shape so I'm going to move it forwards again and now we've got some information coming over here so I'm going to draw a new shape using the add to spline tool this is again using a sort of track as you go kind of workflow so I'm going to grab a little bit of that door there I'm going to add another shape up here as well so now we're using three areas to capture this back wall and to avoid him so now as he's coming across the main part of the screen I'm going to start slowing it down I'm going to go frame by frame just to watch how the track is going and now he's really starting to encroach on my area so I'm going to have to start adding more data behind him and start to tweak this shape here as well so let's just I'm going to delete this point up here move this across a little bit and let's keep on tracking forwards so again he's going to hit that shaped it so we'll just keep on inching that forwards and we'll finish this off here so we'll move this over a little bit I'm going to draw another shape just down here on these objects just keep that detail going I'm going to grab these two points and move them across like so just going to get rid of this point now just to make it quicker and we'll keep edging across so we can see now that you get more information so I'm going to add a new point to this shape pull that down and we'll just edge forward one more it's a little bit too far so he's going to pull back one now I'm not going to get rid of this shape entirely so I'm just going to delete these points so that's gone and I'll just use these back shapes now so let's keep tracking forwards add some more now this shape is becoming useless here so I'm just going to grab all of these points and move them over here and so Kay so these ones down here I'm just going to come down here and I might just delete this one now and we'll just keep tracking forwards so you can see this is actually a slightly more tedious process but it means that our shape is going to sorry our track is going to be a lot more accurate when we get to the final point so I'm going to move all this down now like so and like so let's grab this area and let's keep trekking forwards so now we should be right for the rest of the shot let's see so that grid is still remaining quite solid it's locking on to those final edges and I think my good because we no longer have our obstruction in the way so we can lock on to that and just keep on tracking forwards so I said this is quite a much more lengthy process to track but it means that you're not going to spend a very long time tweaking back in either after effects or Nucor your external application or doing a lot of adjust tracking inside Mooka so I'm just going to scrub back through and we'll have a look at that so I'm going to quickly insert a clip here I'm going to import from my inserts here let's just put our shameless promotion back in to our shot and we'll see how that's looking and that's actually tracked in very very well so this kind of manipulation you can see our shapes are going all over the place they're sort of warping in and out that jumping all over the place but it doesn't matter because the shapes don't actually move the track they're just our search areas so we can add and remove as many times as we like as we go through the shot so now let's take a look at an example where the screen itself almost disappears out of the shot and we don't have enough detail to work with so I'm going to come across to a new shot okay so in this example we have a blue screen that is almost completely going out of the shot but this area is actually quite easy to track we've got a lot of texture data but as we look at the end of the shot we don't actually have that much detail to work with at all even if I up my brightness you need to have a look we've really only got this top little area here and that is kind of difficult so in this case we have to draw a sort of specialized shape to make sure that we get as much detail as possible so first of all I'm going to select my X plane tool again and I'm just going to draw and a big shape around the top of this screen and then I'm going to cut off the screen edges so we keep a little bit of that screen edge and if I turn off my paint mode again we can see how that looks so I'm grabbing the edges of the screen as well as the little bits of detail up here so again there's not much to work with here but this will be enough texture information for moko to help track so I'm going to turn on my pixels here 90 percent and again perspective and in this case I'm also going to turn on my surface but we don't actually see the end of the screen so let's see how we fix that up so I'm going to just set up my surface just lined up on the outside of the screen here like so and I'm just at the moment going to line it up with the edge because I can't see the bottom corner in this particular frame I'm going to have to adjust my surface later to actually see if the actual screen has worked well so now that I've got that set up I'm going to call this one again screen trick always label your traps and we can begin to track backwards so this is now jumping through and analyzing just that little matte area around here but it's capturing all that little subtle detail in the shot so come up here it's grabbing a little bit more of the detail that appears at the top of the screen and then it will actually capture the rest down the bottom and we're going to have to add a new shape when that additional texture information turns up so here we go down I'll turn back on my main view so as we start to come down here I'm going to start adding some new shapes so I'm going to zoom out a little bit and I'm going to draw a fairly big shape here I'm going to avoid the foreground and we're just going to grab that area like that oops you can see here the mistake I've made I've drawn a layer instead of add to Lance I'm just going to trash that add to shape and we'll try that again so I'm going to keep tracking backwards okay so now that we have the rest of our shape we can actually pull down our surface to get the full screen so I'm going to come down to about here and we're going to pull that surface edge down to the bottom corner just like that and again I'm going to use that same technique I used before to just line up the edges to find that bottom-left corner so let's just scrub through the timeline and take a look at it and that's looking pretty good so we can probably deal with that so now that we have this screen it's going to Center that back in the middle I can then export that out to file and in this case I'm just going to quickly bring this out to after-effects so we can see how we would kind of finish up this shot with a particular blue screen I'm not going to go into massive detail but I just want to show you the export data you can use inside mocha so here we have our export options in the export tracking data dialog we have the after effects options which use the corner pin and transform for the most part in After Effects and mocha Pro After Effects you're going to be using the corner pin export for screens rarely will you use the transform data for a screen because you do need to deal with those four corners so I generally recommend using supports motion blur because this will actually allow you to apply the motion blur effect inside After Effects when using a corner pin effect by default the corner pin effect does not do motion blur so we add some additional translation scale and rotation to the layer so that you get the correct motion blur the other options that we have for mocha Pro are a silhouette assimilate scratch Autodesk products avid es borås digital fusion final cut motion nuke Quan tel and good old shake but in this case I'm going to use the after effects corner pin and just copy that to the clipboard so now I can go over to After Effects and then paste this into the shot so here we are in after-effects and I've already got my footage inserted into a composition and we're going to just do a quick insert into this shot so I'm going to throw on my tiger new screen and you can see here that the targeting screen is actually not the same size as my footage now this can be a problem in After Effects because the cool pin is based off the image size not the composition size so it can get a little bit skewed in the shot so the way we fix this is that we can pre-comp this insert and make it the same dimension so I'm going to just press command or control shift C will bring up the new composition and we're just going to say move all attributes with the new composition and I'm just going to call this one target screen square insert and click OK we can then go into our computer and we're just going to select the layer and go up to layer transform and choose fit to comp and then the insert will stretch to the full dimensions of the comp so I can close that now and now when we select our insert we can go up to edit and choose paste and our corner pin information will sit in the correct spot so we can just drag it through and you can see that's sitting in the right spot now to wrap up this shot we want to actually blue screen out the front I'm not going to do a complete kit here but I'm just going to quickly show you an example of how that would look so I'm going to duplicate my background layer I'm going to put it on the foreground layer and then I'm going to do a quick key light so I'm going to come into key and use key light and then we're going to pick this and we'll find a nice area let's just drag this out of the way and we'll find a good area to work with about there okay and now we've got this sitting nicely in the view with our shoulder sitting over the top and the manas has got a nice little soft edge on it because we've done the key and then we go through and add the additional grain and all that kind of stuff but that's basically how the workflow between the corner pin expert in mocha and the king inside After Effects would work so that's a tracking a difficult shot using the edges of the screen and now we're going to look at attacking reflections okay so back inside mocha let's load up our next file so this is a common situation we've got a very shiny tablet and the only thing we can see on the tablet is reflection we've got some trees here we've got some power lines and we've got a face as well and everything is really high contrast and in sharp definition so that reflection is going to be treated as a plane by mocha so how do we avoid this reflection we can't really track the actual plane itself and we kind of track the background because it's too far away and it's not moving so the way we do this is we try and give mocha as much plainer detail as possible without actually giving it the full information so to do this we draw a large shape around the edge of our plane so I'm going to go all the way down like so grabbing that whole area now this by itself obviously is not going to work because we've got that plane captured so the next thing we need to do is draw a new shape inside the layer using ad spline to layer and then we cut out the edges so I'm going to come around here and just cut out as much as possible to get right down the bottom here grab that edge you come around here make sure we've got all that and I'm also going to just a little add a little bit more there let's say that's about that so we're going to use just this edge area to try and capture that plane and it may be enough you can see here we're using some of the thumb and the some of the thumb on this side but we're also grabbing the edge past that thumb as well just to capture a little bit of where the thumb detail meets the surface so I'm going to turn on my surface and my grid and we're going to do the same thing we're just going to line up our surface area let's just do it roughly quickly first and then we will line it up with those edges of the screen I'm going to turn up my grid for a second just so we can see a little bit better and again I'm going to use those zoom windows to make sure my corners in the right spot let's just turn off the layers as well so we can see so that's lined up there and we'll line that one up about there that's looking pretty good so once we've got this we can now begin our track so again we do all the fun stuff we turn on the 90 percent pixels we turn on perspective and we call it screen track I'm sure you're sick of me saying that but it's very important to name your layers I'm also going to save my project so that I have it ready just in case I want to make any changes so I'm going to turn off a few things here let's just turn off now we'll turn off the layers and we'll just keep the grid in place and then we can start tracking forwards so we can see there it's actually locking down really really nicely and now when we play back you can see a nicely locked off screen using just those edges so let's just turn back on that mat and we can go ahead and insert something here so I'm just going to import something here let's import our make a logo again like so now that's actually the wrong way around so I'm going to actually rotate it in space so I'm going to come down to my insert tool I'm going to go to my rotation and I'm just going to set that to 90 so now that we've got this we can either again choose to export it out using the export offset data because I've rotated it 90 degrees I would export offset data from mocha Pro rather than use the export track alternatively if you don't have the insert tool and you're using mocha for After Effects you can just let's set that back you can actually go back to the track and actually manipulate your shape so we can actually move these corners around and do it that way but because I've got the insert tool I'm lazy so I just said in 90 degrees and do it that way so there's many of one of the advantages of using it we go pro so again we can just export that out using the tracking data using our terrific's corner pin and again we can copy that to the clipboard and bring it out to whichever application we need so I'm just going to cancel that because we're not going to show that one today and finally we're going to go through some lens distortion techniques to show you how to insert screens when you've got to deal with lens warp okay so let's load up a new shot so here we have a simple pan down shutter it's going to brighten this up a little bit and if we drag through this shot you can see it pans and then it turns to the side a little bit there but we also notice here that we've got a curve in our lens that we need to accommodate for when we insert into the shot so how do we do that we can use the lens tool inside a mocha Pro and mocha a 8 now I need to emphasize that the lens tool is currently only available in mocha ae and mocha Pro that you buy from Imagineer this lens tool is not available in the bundled cc or after-effects versions of mocha AE so we want to use this lens tool to actually calibrate the lens that's in the shot so to do this we tell moko to locate the lines in the scene just by clicking and moeka throws up a whole bunch of lines and says hey did these lines need to be straight and then we need to tell it which ones actually do so for example over here obviously this line here we want to keep curved but this one is actually supposed to be straight so what I do is I'd use new line or I press the Enter key and I do a little bit of a join the dots to say moko you need to make this line straight so adjust the lens accordingly so we want to tell it a few lines to make sure that it calibrates the lens correctly so I'm going to press n again and I'm going to get this bottom part of the television and I'm going to do the same on this side and on this side and you want to create any line for any new segments that you make in a different area now if you don't have a scene that has straight lines in it you can actually bring in a calibration grid to help you out using the calibration clip by default it just uses the input clip now in this case since we're talking about screens that's probably not going to be necessary you will have straight lines in the scene because you're using screens so in this case we've got all the lines that we need and about four around the screen is enough and then I'm going to set the parameters for the calibration so we have one parameter distortion and this is basically a barrel distortion so it works at a point in the center and then warps from those points based on the lines you've selected to calibrate the two parameter distortion is very useful when you need to work with them or warping lens so for example a fisheye lens often has a little bit of a warp that flattens out on the edges before it bulges in the middle so that's where the two parameters useful and then we have anamorphic and distortion Maps the social maps are very useful if you're say done a lens distortion in say nuke and you've rendered out an ST map you can bring that inside MOCA to use there but here I'm going to stick to good old one parameter distortion and this is probably the classic case of distortions and then we can just click calibrate so you can't see much of a change here because it's a subtle distortion so I'll turn on the grid and we can see that warp a little bit more obviously so once we've got our warp we can into how do two different things we can either choose to render it flat so I'll turn off my grid for a second and render and that actually renders our object flat we can choose to track into the shot which is what we're going to do here and that will actually distort our inserts with the lens distortion and we can also export the lens data which we're also going to do in this case to show you an example inside After Effects so I'm going to start the track first because we want to deal with that and then I'll come back here and show you the lens data options so to do this I'm just going to turn on my spline tools let's just start drawing a shape here and we're going to do a very basic shape around here and I'm going to go to brighten that up just a little bit cuz it's quite dark this see and we'll pan down a little bit and I'm going to make sure I get all of those edges now when you draw the shape you're going to notice that it's you can't really notice the lens distortion but when I turn on my surface we can really start to see that warp that's in the lens so I'm going to put that to fit the edges of my screen and again I'm using the top left hand corner to zoom into those corners to make sure that they're sitting just outside that edge I prefer to sit just outside the edge so that I've got a bit of wiggle room to work with when I do my composition later so I've done my four corners now and again our happy little friends ninety percent pixels perspective and screen track so we've got our warp and we can now begin to track so this is it will now track with the lens distortion in place so I'm going to start tracking forwards now as I come down here because we have a fairly blank plastic sort of edge here there's not a lot of texture detail so I'm going to stop here and actually draw a new shape and again using our information that we used in previous examples I'm just going to use something that looks like it's on the same plane I'm going to draw a little shape down here so now we've got two shapes and we're covering the with a section down here this is just to make sure that when we get to the bottom corner our surface does not slip so let's keep on tracking now in this example we could go ahead and use the same lens distortion to track every single screen but you'll get the general idea from this specific example I don't want to bore you by going through every single screen in this example so we'll keep to the main shot just for the time being now when we actually record this I may actually pause this and just edit out the boring track part of this shot okay so now our track is finished we can have a look and see how that's going and we can still see a little bit of distortion happening at the bottom here so we're going to do the same thing as we did last time this is actually looks like a very casual drift that happens so I'm going to go back over to adjust track and we're just going to deal with the bottom two corners so we'll come right to the end and you can see quite an amazing drift happening there so I'm going to come down to auto and my bottom left adjust track and just pop that back and the same with the bottom right and let's just have a quick look now back in the main window we'll just zoom out a little bit and we'll just drag that through I'm pretty happy with the way that looks so we can go to now go into After Effects to finish off this shot so the way we do this within the adjust track module so I want to actually use export dragging data from adjust track so I'm going to export the tracking data and again I'm going to use After Effects corner pin now here's the difference when we work with the lens module to understand the track regardless of the type you're doing whether you're flattening in the shot or you're adding back into the shot when you export your four corner pin you want to remove the lens distortion from your shot the reason for this is that if you flatten the shot you need to remove the lens distortion from your insert so that it sits in the scene better in art effects but if you're actually going to apply the lens distortion to the shot you need to remove the lens distortion first so you can apply the lens data back on top to curve your corner pin and this will make a lot more sense when we bring it in so I'm going to remove the lens distortion and copy it to the clipboard now let's go over to After Effects and we'll continue the shot okay so over in After Effects I'm just going to get rid of this shot and load up my lens so I'm not going to save this particular shop so we've already got our footage loaded in here and I'm going to bring in an insert let's bring in another targeting screen and I'm going to just drag that on top of my footage here so when we paste in our tracking data by just going to get it and paste you can see it's actually sitting right in the same spot but it's very very square this is because we haven't applied the lens distortion yet to the shot so to fix that what we need to do is we need to pre-comp our targeting screen first because we want to apply the lens data to the entire comp area so I'm going to pre comp and move all the tributes because we want to move that corner pin inside the pre comp so I'm going to call this one target screen insert and then I'm going to go back into mocha Pro to finish off grabbing my lens data ok so inside mocha Pro we're going to go back to the lens tool and we can go to the export lens data button so in here we have a few options we've got mocha lens data for After Effects and this is available in both mocha and mocha Pro but we also have distortion map and that's only available inside mocha Pro the mocha Pro distortion map lets you render out a UV map to things like new confusion and smoke to do illness distortions that way but we won't cover that today if you want to actually check out how the distortion Maps work you can check out our other tutorials on distortion so I'm going to choose the local lens for After Effects today and just copy that to the clipboard and then we can go over to After Effects okay so back over in our projects we've got our pre comp done and you can see there the four corners of our comp set it to the full screen and again all we have to do is cut and say paste because we've got our lens data again on the clipboard and now it's actually warping the shot you can see it's actually warping it the wrong way and this is because initially the effect actually undistorted to go to our effect controls so under the mocha lens plug-in we have a few options here to define the footage width and whether or not it's the comp size or footage size but here I want to instead of removing distortion I want to apply it now you can see the curve is actually sitting correctly in the screen if I turn on and off the effect you can see now that it's actually applying the distortion correctly in the shot now if we wanted to do the reverse of this if we wanted to actually export out the flattened version we would have to apply the lens effect to our fridge layer and use the remove distortion before we pasted our tracking data so that's the two workflows you've got either to paste in the distortion to your insert and apply the distortion or select your footage and apply the remove distortion to flatten out the actual footage layer of course the other way you could do this is actually not use any of this at all no pre-comp no data no mocha lens what you could do instead is use the render tool inside a mocha Pro so let's go back over to mocha Pro and have a look at that right so back over in mocha Pro we've still got our insert in and I'm going to go back to my track tab and I'm going to use the insert clip to bring in that insert that we chose for After Effects so I'm going to grab the targeting string open that up and import it and now we've got our shot sitting in the screen with the correct distortion already set up now the advantage of this is that we can now go to the insert tool and actually do some free composition work before we export it out as a render to after-effects so to do this we can either adjust the opacity or we can adjust the gain to brighten that up and in this case I'm just going to keep those as 1 and 1 because I want to do that work in side after effects but it's good to be able to adjust quickly adjust these things if necessary you can also show the mesh so I'm just going to turn off the grid for this and show the mesh the mesh is like a mini grid that lets you actually warp your screen to actually officially adjustments I'm going to again not bother with that because we've got a nice easy story to work with you but keep in mind the warp tool is a very powerful tool to use if you need to do any kind of quick distortion work especially when you're working with cloth all I need to do tiny minor wharf adjustments in your shot it's a very useful but often underutilized feature so check that one out so I'm just going to undo that whoop in this case I am actually going to apply motion blur so I don't have to do it inside mocha and because I'm rendering the motion blur would not apply anyway so I'm going to do motion blur at about 0.25 and I'm going to leave my comp settings alone we can set the comp settings to actually apply the layer map to help cut out things but I'm just going to do a plain old render with motion blur so let's just turn off that mesh and we'll start rendering forwards so now what this is doing is actually applying the motion blur of the camera that we've tracked with the lens distortion and then rendering that out to file now the good thing about this is that actually does a few passes it does a composite pass and it also does a layer pass so it means that you can split out the insert with an alpha and apply it back inside After Effects as an additional comp we also deal with the layer mat so if you want to set up a more tight mat around your insert you can also render out the mat and then use that as a track mat or round your screen edge to sort of get a really nice Compton shot in this case I wouldn't do that because we had some green screen going on here so I would actually do a key but it's good to know all the options that are available to you so I've done that render now and that's almost finished at the edge there so now we can have a look at that we've already rendered the composite and we've also got a layer file called layer that gives us our alpha channel with the insert we can then go ahead and then export a rendered clip of that layer so I'm going to come up here and it automatically selects our laugh arm and we can start to export out the render settings so I'm going to choose an image sequence and I'm going to choose in this case a tiff sequence and I'm going to choose my folder so I'll choose my mocha screens demo folder and we'll get our insert render folder and choose that and we'll leave the prefix alone it's got a nice layer there and I'm going to click OK and now that's exporting out my clip I've rendered I can go back over to after-effects and then import that entire distorted and motion blurred clip into my shot okay so back over in our tropics I'm just going to delete my data insert that I did with the lens tool and my tracking data and I'm going to import a new file so let's load that up I'm going to come to my insert render folder and we're going to select our layer and I'm going to do it straight and unmet it and we'll make sure it's the same dimensions and same frame rate so 24 frames per second as well as 93 frames and then we can drag that into our shot and it just sits immediately in the shot and works so you can imagine this is a much faster workflow to work with you've got a motion blur pre-rendered map file in mocha Pro that just dumped straight into the shot and then you can start playing around with it it means that you're not having to render an effect you're not having to render motion blur it's a whole lot quicker to do it inside maker pro preview it very quickly with our fast render coach tool and then render it out as a clip and bring it into After Effects so there are the two workflows you can either use mocha Pro to render the insert or you can use the export of tracking data and the lens plugin for After Effects and bring in the data so you've got a bit more sort of flexibility with changing effects and changing keyframes okay so that's all we've got time for today but let's quickly go through a summary of what we covered today so we can track anywhere but the screen in most cases you want to avoid the screen itself because it's a big shiny glass thing that reflects everything and shows either little detail or too much detail you could fix this with tracking markers but that's more post work you have to do so if you can avoid tracking markers and track everywhere else around the screen definitely do that method now something we didn't really cover today but I want to emphasize is scrub your timeline at least a few times to see where you can track and this will really help reduce the amount of tracking that you have to do so in the case of the rocket jump shot with the guy walking past the screen we had to go through and look at the wall a couple of times to see how it was going to move and then as we tracked forwards it was easy to kind of move and adjust those points as we went but we really had to sort of focus and make sure that we looked at our track as we went thirdly we want to avoid those reflections reflections are another plane within your surface so Mokka will look at that and track that instead and often with screens the reflection is actually the most detail that you'll have in a shot which is really annoying but we just have to live with it now we have to use a just track in a lot of different situations we generally try to use it when there's drift occurring and you saw me use that in a couple of situations there but it's also really useful for finding corners that we can't see and finally you can render too juice your time elsewhere this is really handy for that final shot where we needed to do lens distortion and tracking and motion blur all in the same insert and we were able to do that all inside mocha Pro without having to export the tracking data and then export the lens plug-in data and then do a final composite inside After Effects finally if you want to learn more about mocha AE and mocha Pro you can go to the internet and go to imagine air systems comm where we have all of the product information tutorials documentation and so on we also have a tutorial sites at vimeo.com slash em engineer and youtube.com/ imagine air systems we have our facebook site at facebook.com slash imagine air systems and we have the Twitter feed at imagine air system - the s because Twitter only allows 15 character usernames and check out the hashtag mocha tips on both Facebook and imagine a system where we post short little tips about mocha Pro and mocha AE so that's been trekking screens with mocha I've been product manager Martin Brennan and we hope to see you next time for another webinar

Channel: Boris FX Learn

Views: 116,968

Keywords: mocha Pro, Lens, Screens, Tracking, VFX, After Effects, Tutorial, Webinar

Id: BBhjb3TSu-8

Length: 55min 56sec (3356 seconds)

Published: Fri Dec 06 2013