Blender 2.8 Motion tracking #4: Camera tracking examples (tutorial)

welcome back though Bunder users to part four of the motion tracking tutorial series and like I said in the last part we're just gonna be doing some camera tracking examples in this one so for everybody waiting for object tracking I'm just gonna make you wait a bit longer for part five but it is coming and then you will know the sacred skill that you guys keep talking about we won't object tracking we want object tracking it's coming but first stuff to hit you over the head again and again with how to do camera tracking because object tracking is essentially the same thing so this is something we need practice in we have two more shots to go through I think I actually showed them in the last part but why not show them again so we have this second moving shot which I always forget to remove the audio for so we have the second shot who's a bit out of focus in the beginning but when I exported this as an image sequence I'm sure I cut it off so this is actually an example with a very clearly defined floor and wall which wasn't the case last time so we'll go through an example like that and then the next one is just the tripod shot again this is also called a nodal pan where the camera is still on a tripod and it's just pivoting around like this so there's no parallax you get from actually walking around which actually makes the solving process a bit different so we're gonna talk about that so without further ado part four more camera tracking examples let's open up blender and now we're actually using I always have to wait to say this because of the gray screen but it's still faster than opening other 3d packages we're using release candidate version two which is very exciting but we need to do the things that I keep saying over and over and over again do you know what they are yes one of them is indeed your right is going into the render tab color management color management and then changing filmic over to standard so our footage isn't graded in the filmic tone so we just have standard and then indeed haven't used blender in a while indie content no and the output tab I don't know I even forgot that I haven't used it in the day so whatever and the output tab we are gonna change our frame rate to 30 frames per second because that's essentially what I filmed it at and in the movie clip editor which is where we do pretty much everything related to tracking we're gonna open up one of these image sequences so tracking camera track shot to sequence and then import that all in and by the way I'm thinking of at some point releasing releasing all these sequences so you guys can actually use them I'm still trying to figure out how to do that because it's a lot of data but eventually you may have your hands on this so set scene frames to make sure we're going from 1 to 161 so we don't have extra long timeline here we're gonna prefetch to load the symptom Emory you know the journal again this is just a review it's kind of a intermediary tutorial episode and for this tracking I'm gonna use for most of this I'm gonna use the affine model to get the deformation and the shearing and then when we do some of this brick stuff it might be better to actually go all the way with perspective so affine will work for this we don't need to go all the way let's enable and normalize to make our lighting intensities not an issue again invariant to lighting intensity and then our lighting changes I guess I should say and then let's see in tracking settings extra we're gonna use a correlation of 0.9 which again means we need a 90 percent matching tolerance for it to keep tracking otherwise it's gonna stop again we reviewed all of this before and with all that said and done let's pick a very obvious candidate for tracker again I'm looking for things that have high contrast features and that I expect will last throughout the majority of the shot with high accuracy and this should probably do it so alt s for the search box make sure that is nice and big enough and let's open up our tracking menu so we can see what we're doing we can reposition this and then locking with L we control T to track forwards did that last the whole shot you bet it did so ctrl L to lock and let's pick another and we could pick this one next to it but again we're not gaining that much new information from doing that we want to have our trackers distributed to D distributed a lot in this 2d space so all around our shot and also in 3d so these two these two spots are very close to D and 3d so we're not actually gaining that much out of it instead I feel like this is far enough that we'd actually gain something by tracking it so let's do that again the main idea of camera tracking is really the theory of which trackers you should pick in the first place it's not how to do the actual tracking which is something we've gone over okay so this only survives 78 frames so we're just gonna lock it and we'll see if it pops and again because maybe we can do a joint track it does pop in again so let's handle that we can add another tracker and then control t to track forwards this one made it to the end and then finding where this track started we can go back with alt left arrow to get a couple extra frames okay let's lock that and then go back to this tracker shift clicking it so we have both selected and then track join tracks so now we have a single track that we can just play it so it goes here it cuts out and then it comes back if we go to the graph it's gonna be kind of hard to see if we don't isolate this from all the others but you can see there is a gap in this highlighted one and this is where it doesn't exist just a lot of review but it's very important and this is a good example to show you how fast you can actually do camera tracking when you're not explaining every single aspect of it at in depth so let's see what else can we find on the floor I like this little white dot that's control T that boy okay it only made it this far perhaps we need another reference point so we'll just scale that down and maybe increase our search box so it doesn't leave the search box if that was the issue control T okay that made it all the way to the end that makes me happy pat on the back what else can we do on the floor before we move on to this wall we can try this one in the distance I like it a lot because we have a lot of difference in this one relative to the others in terms of where it as 2d it's all the way on the left of the screen whereas these ones are on the center and in 3d it's a kind of further down this alleyway this very weird alleyway that I decided to motion track but will disregard that control T okay so that's good up till then if you're doing this professionally like for a client you might want to review all these trackers make sure they're not shifting around but I have a good sense that that's not the case for here and does it come back of course it does so we're gonna do another joint track kind of deal and I don't think we have already have we saved we have not we should probably save just in case we have a crash we are in release candidate 2 so hopefully it doesn't crash we'll call this tracking for fun that's what we're doing here ok so track backwards shift control T perfect and after this you guys are gonna be absolute pros at camera tracking and you don't have to thank me you worked very hard at it control L and that that's a shame it almost made it to 161 but it didn't and that's fine so we need this one selected and then go back shift-click stab both of these selected join tracks and then let's try to get one more on the floor before we move on here and we don't need to just use dots even though they're here and they're very convenient there's no reason we can't use a more complicated pattern like this failed attempt at graffiti you know we can just pick the corner this maybe rotate it there you know what I'm gonna take something further away from the wall like right here scale that up again since it's a fine it's gonna kind of simulate these perspective changes and you know what since we're doing a pattern that's you can really tell the perspective change on this one I'm gonna change this true perspective so tracking settings individual to this trackers not here but here we're gonna change this over to perspective mode and then control T and it's gonna take a bit longer not much longer lock that in and you can see that this is stretching because we're moving closer to it but again all that matters is the center point does that look like it's remaining where it's supposed to be we review over here it should just be on the tip of this s looking thing yeah that's very good so control L so at this point we have like five ish trackers some of them are blinking in and out on the floor and now we can focus on the wall now you may think to yourself that this is a very good surface to do tracking and it is there's lots of detail but the issue is it's very repetitive so we may run into an issue where if we're tracking this right here this intersection of lines on the bricks that's a very good tracker however it may mistake it for this one because they look very similar so there's a lot of pattern and repetition that's not necessarily good so we need to pick something with some extra detail so it doesn't jump around and a nose which brick we're looking at so anything that includes like a dot like this that's unique or maybe some color like this is gonna be very easy to hold onto as opposed to just picking something randomly so like I said we're gonna do perspective for these bricks and let's start off with the obvious option doing something over mmm we could Center it here but I don't want to get this other 3d object in here so I'm gonna go a bit higher scale that up so it's containing some of our it's that brown or orange and can't tell but we want to contain some of that and hopefully that is unique enough so that when we hit ctrl T yeah it looks like it's grasping on there we want to review ideal you pick the center point to be like a little dot right here so you can tell if it's staying on because here we don't really have any reference but I do think it's a safe bet to say that this is tracking on we're just gonna go for solve errors of under point you know point seven point six that is our goal for all of these because that's what you would need to do in a real environment where you're tracking shots for a movie or something well I guess if you're doing it for a movie they want like under point two but we're not gonna be that strict we're gonna be a very you know accepting movie studio that doesn't care too much so again I'm looking for bricks with a lot of unique details here like these dots control T okay we got a lot of motion blur here so we'll see if we can actually get this ourselves first of all we want to try the manual approach or sorry the automatic approach before we manually try matching this so we're just gonna add another reference frame by changing the search box and probably won't match on Bowl see oh it did this time and blender is much better at seeing where this is going than I am usually although we do have that human a sense to see where it is but I do like blender doing the work for me okay we can get some extra frames it's over here on the margin so we just need to scale this down a little can we get extra frames okay one four three scale this down all trade arrow okay we got 144 and then I think we gotta let this one go so just let's review this tracker since there was some motion blur issues does it look like it's staying on there it does okay that's a good tracker I wish it stayed on the whole shot but that's fine what else can we get let's try to get this one right here scale that up and hopefully you guys are getting very good at doing all this tracking process and what's very close to real-time I don't even know what that means I just mean fast cuz camera tracking unless you have a tricky shot I haven't done any tricky shots on this tutorial series yet any shot that you have seen here you should be able to track very quickly is the point I'm trying to get across okay what else can I do I'm gonna go back to the floor trying to get stuff over here in the corner because we haven't filled that area even if it's only for a couple frames we'll do an affine track on this one probably only gonna get 30 frames out of this 56 better than I expected and we might be able to recover some more wood joint racking we'll see no because I move the camera physically forwards so we don't actually get back to that tracker okay so that's a locked we'll leave it as is and it might be a good strategy to go to the last frame shift right arrow and then see that we only have six active trackers currently so let's add a tracker over here scale that up and then track backwards which again is a bit slower but it's fine that's shift control T or you can just hit these buttons or just hover over them and it will tell you the shortcut so this is one frame backwards and then this is all the frames yeah shift control T so will tell you the shortcuts if you ever forget but hopefully you don't forget because I keep saying him out loud not to annoy you but just to make sure you have this in memory I think it's important what else let's get some stuff on the wall here changing back over to perspective so we can always change between motion models it's really not a big deal pick up some of this we can even rotate it so it goes with the bricks it's not really gonna help but something interesting to do shift control-t I expect this to be very slow because we're going backwards and doing perspective but very soon we should have eight active trackers throughout the whole shot so that's good and again it doesn't have to be the same eight trackers just at any frame there has to be eight active trackers and those can blink in and out of existence as long as there's always a set of eight and while this is tracking backwards I'll just tell you about an email I got about this motion tracking series I've gone dis comment also a lot in my videos for the creating image sequences thing when we go over to know the video editing workspace put in our footage and then exported out as an image sequence there's nothing wrong with that but there is a faster approach and that is using you know ffmpeg you're doing some commands on the console so if you want to mess around with a bit of coding there is a faster way to convert over to image sequences so adding a new reference frame here and this will be a bit faster since we scale things down I can't remember if we scaled down the search area or the pattern area but either way there's less to go through less combinations means faster I think always always okay frame 40 going backwards so there's only 30 or so to go through and we can see right here that it's really staying on this dot so this is a quality tracker okay lock that in and let's try to get one more cuz how many do we have now we do have eight but I do I would like to have one more that lasts throughout the whole shot that would make me a bit more comfortable with what we have going on here and we can always add more trackers after trying to do a solve let's go for a fine put one here and this isn't the greatest dot to use because it doesn't have that much contrast you're going from this purplish you grade to something that's a little lighter so we can either scale this up to contain one of these dots but that's using a lot of pattern area so it needs to look through a lot of combinations what I would recommend is maybe picking one of these dots that has higher contrast but hopefully we don't lose it in motion blur so we'll see okay I made it back to frames see what the issue is does it just need a new reference frame might just not be a very good tracker i'ma give up on this one the motion blur is distorting it too much that it doesn't seem to pick on to this let's try something different all trial and error here Ivan tracked these shots before recording this tutorial so hopefully we got a good solve live so I show you the actual process I'd go through so shift ctrl T so this one seems to be working a lot better of course it's gonna blink out of existence but maybe it will come back so it's the dot above this graffiti is just what I want to remember so I can match it right here always important to not match it to a different dot see like oh it came back and you put it right here not not good at all because then you've basically said that it moved to a different location and will interpret that as camera motion that doesn't actually exist so we can track forwards a little and then once we do that we'll just go all the way back okay lock that in and then find the previous one which is this one shift-click and then join tracks and at this point we can count them or somebody actually said if we go to the VFX workspace which is I don't know where it is you have VFX motion tracking it will actually give us a dope sheet that tells us how many trackers are active on each frame but I'm gonna assume that there are actually eight active trackers here and we can head over to solving again I don't want to pick keyframe a and B for myself this is the range that it's gonna do a camera solve and then it's gonna extrapolate that construction so it's very important the a and B it's gonna be doing all the heavy work between keyframe a and B I'll have it automatically choose a good pair and then tripod we leave disabled because the shot is moving in space I'm holding my phone which is what I'm recording it with and walking so it's not staying in one spot like a tripod wood or a nodal pan so we're not gonna do any refining yet I think we'll just do it as is so soft camera motion hopefully we get something acceptable or maybe hopefully we don't yeah we don't here here we get one 45 so we can start talking about the troubleshooting process and this is the frustration people usually have with the camera tracker and blunder it's very good but sometimes you get these crazy errors where you shouldn't so what we're gonna do is we're opening up a graph here is what I'm doing just so we can see so you can see this blue which represents our camera solve is all over the place again we want this to be perfectly flat so before giving up and trying some different things we need to make sure that we do a couple camera selves if we always get one 45 then we need to change something so here we get 25 which is not acceptable but you see it's not as disastrous as 145 I like to hit this button like five or six times especially when I'm sure that these trackers aren't too bad and then if we always get high numbers we're gonna just add some trackers so right here we got one point two one five which is reasonable that's a number that means okay and knows kind of what our cameras doing and this I mean I'm I kind of wish this happen in the first tutorial where we introduced camera tracking but this is oftentimes the case you have to spawn a bunch of times sometimes to even get a acceptable solve error but once we have this we can actually begin refining so we're gonna turn off key frame a and B and then hopefully if nothing changes if we solve now because we have these set nothing should change yes so we're now stuck on one point two one five and now all we can do is really improve this so we can change the refine so tries to guess the focal length the k1 k2 which is the barrel and fisheye distortions basically its lens distortion in two different types of concavity you don't need to know about this it's just guessing your lens distortion and then we can also do optical Center yeah we can do optical center again this is where the center of your footage is right now it's guessing that it's right in the center of this frame but this is depending on the curvature of the lens whereas the kind of the center of it if you were to blast a lot of light into it and usually it's not a perfect cone down the middle so we want to have it refined for all of these we'll see if it actually does a good job at this okay so we're now down to 0.78 let's see what happens if we hit it again okay so it's secure on point seven eight so now we're gonna turn this off so it's not refining for anything so if we hit this again I guess it changed a little but it's pretty much stuck on point seven 807 which is much better than one point two one and again now we can do some manual some manual correction here and the first thing I always recommended is looking over at these graphs and looking for anything that looks weird and maybe chopping it off so for example in this one right here I'm wondering why this is diverging at the very end so let's see okay so this one kinda seems to make sense because it's very distant from the others so might have some different X behavior which is what the grid graph is but we can always try trimming it off and see if it makes our saw there or worse or better so we can trim this off like this actually we can't in this case and the reason why is because this is a join track so you see blinks out of existence and then it comes back so by clearing the right we've actually cleared the second part of this tracking and you can go manually and disable the frames like specifically these frames but I'm not gonna mess with it so that is one case where join tracks is actually troublesome I wish there was a button to have a range where you can cut off frames hopefully that's a feature they can add or I feel like that's a very easy add-on to make okay let's see for other behavior that doesn't look good okay this doesn't look too hot at the very end it shouldn't be diverging that much at the very end so let's try trimming this it will either make it better or worse so this made it better so we went from point seven eight two point seven seven something so that means it's something in the right direction so is you always want to do a tiny correction and then check if it made your thing better or worse okay why is this so different okay it's because it's way over there and it's pretty much separate from our other trackers so that makes sense and since most of our trackers were pretty good in this case I'm not seeing too much divergence but it will be usually very obvious like you have something shoot off where it doesn't make sense at all but I'm thinking that other than this right here which we could go in and correct I'm thinking that this is all pretty good so the next resort I guess it's really the last resort is changing our weight factors again right now what it's doing is each one of the has its own air which we can show with info so each one of these is gonna have an average error so this one has 0.7 for 7.4 54 which means it's better than the last one and it's taking all those errors and combining them so if we make the ones with high error or worthless we're by bringing down the weight it's not contributing as much to the solve that is better for us so it's a weighted average is what we're creating here so I'm gonna turn off flaw and I like turning off the video here so we can really see the text I'm looking for the worst defender so here we have one here we have 1.3 yeah 1.3 is probably the worst so we take this one and bring down the weight halfway see what else is doing not too hot and by the way when this text is read it just means that the tracker isn't active right now so this one probably comes in towards the end of the shot yeah so then it turns yellow so that's all that red means we can take this 1.1 bring it down halfway and maybe you there's one more that wasn't too good yeah this 1.03 7 isn't as bad as the other so bring it down to it like 0.67 I'm not doing this very accurately let's do another solve see if it helps okay now we're in point 5 9 territory so let's do one more a swipe or wipe or I don't even know what those words mean one more process of this and then I think we'll call this good so point eights not too good what else yeah point 8 bring this down even further and it's pretty much expected that the one that's pretty bad was the one we edited before because just by bringing down the factor or the weight doesn't make it a better tracker so we expect this to still be pretty bad same with this one we'll bring it down even lower and 0.76 7 pretty much all the trackers we have to fix the last time we're just fixing again ok I'm pretty happy with that so let's get point 5 2 and we could try to go under point 5 I'll do one more quick processing of this bring down the weight even more or we can be a bit more drastic with us what else is bad this one's new so bring it down just over see what that gives us okay so now we're under 0.5 and I'm very happy with that we can go down to 0.3 but you know there's there's only so much you can do with a shorter tutorial the least I expect this one to be shorter we'll see about that okay so if we look at our graph here the blue line which is representing our camera solve is relatively flat there are some hiccups and you expect those hiccups to be where there's more motion so around this area right here where our x-axis is moving all over the place our X motion really but this is relatively good so we can use this so let's bring this over to the 3d viewport and now we are done with the camera solving and we're onto the process of bringing this into our 3d viewport with some orientation so to do that once we're happy with this we just set up tracking scene and now our camera will be moving when we play it but like we talked about this isn't gonna be it's not gonna look like the plains resting on the floor and that's because these trackers represented by these things that look like empties but again we can control it with our overlays like that they're not resting on the floor like they should be we can fix this manually or automatically which which is what we're gonna do first so we're gonna pick three of these to be on the floor is the main attack for our orientation so let's pick this one this one and this one and we can imagine the triangle that forms that we want this polygon to be on the floor so let's set this to the floor and now our camera moves so that our trackers at least the relevant ones are on the floor and then the rest of these like this one is probably representing on the wall so let's play through this okay so that's looking somewhat better still want to make some modifications for example everything's a bit too big so picking two trackers we can set scale so that's one unit in between them let's make it so everything smaller by making it two units in between them okay that's that's looking at all better and for the rest stuff we can fix we can make an origin so right now it's resting on the floor but there's no Centrepointe so we'll pick this one to be our origin and then there's no clear candidate for an X or y-axis relative to this origin but if we just go along this line this one's pretty close so we can say that this is our I guess x-axis it doesn't really matter x-axis that's looking pretty good and now if we're not happy with this and I think we might be the rest of the orientation stuff we can do is we're gonna do manually so going over to the side view we want to make sure that these are resting on the floor what is this one this tracker should be on the floor so it's not perfect what about this view hmm yes this should definitely be on the floor so what I'm gonna do is with this camera I'm gonna lower it just a tiny bit and add a bit of rotation there's only so much we can fix here okay that's looking a bit better and then in here yes these are a bit below the floor while these are directly on it so we can rotate this way assuming my camera's not inverted so rotate fix that a little okay I think that should be much better and then finally yeah okay so in our camera view finally since this isn't perfectly the x-axis we wanted we wanted it to be along this line we can just rotate selecting our camera r for rotate and then Z and this will rotate on the z axis and we just want this red line x axis to be parallel to the line we talked about and then we can just redefine our origin so that's G for moving the camera and then along the green y axis just bring that over okay so now we can close this up and see what we have here and it might be useful to actually include a timeline just so we can see what frame were on by the way animation nodes is installed for anybody interested in that I'm starting a series a little cross-promotion okay make sure that this is sticking on fairly well and that there's no obvious errors yes so that's looking pretty good and now we have this interesting case where we don't only have a floor but we also have a wall so we can reconstruct that geometry that's a bit more complicated than just a point on the floor so I don't need this cube and for this plane which is should be set as a shadow catcher I guess we can check by going into the rendered view and then in two cycles cuz Evy doesn't have a shadow catcher right now yeah so that is a shadow catcher which hopefully they will fix soon because it doesn't work the way used to again we can go to film enable transparency yes so that's a shadow catcher since we see transparency through it but it's not actually lining up to our geometry so we can move it so G and then Y and line it up against the wall just like that and we can play through this to get a different angle yeah that's still looking like it's in the correct position and then in edit mode we can select this edge and then extruded upwards like that so now we have a shadow catcher that is it's not just the floor but it's also some more geometry add some kind of fly in front of my face we can also make this to go further out the x-axis and of course this edge right here is way too far out it's not even in the shot so there we go that's some geometry and this is just gonna be a shadow catcher and to make this glitch out a little less again shadow catcher doesn't work the way used to we can go over go back to object mode go over to the camera and let's bring up this opacity of our background so it's opaque so alpha 1 hopefully yeah that made a clutch out a little less since it's not China take these two transparencies and overlay them where one is an opaque okay perfect so now if we add in an object like a monkey like we did last time you can add in whatever you want and the side view we can make sure that is aligning correctly okay so now I'm rotating it so it's actually looking at us so now we have this but again the shadow catcher isn't doing what it's supposed to do which is to have its shadows and that could be for many reasons I think the one reason that this is happening is because of the foreground background issue we talked about again in the compositing it automatically makes a foreground and a background so going to the background layer yes so it's separated it into the background layer so we're just gonna do eat this layer and then move this from the background collection over into the foreground and then delete the background collection so now everything's in one and then just to be extreme in this scenario the shadows are not gonna do what what I'm about to do to the shadows isn't gonna be very representative of the lighting of the scene but I just want to show that the wall as a shadow catcher will also pick up some shadow so here you have some shadow on the floor and then it's going up the wall over here we can make that even more extreme yeah look at that it's casting this giant shadow on the wall okay that's looking good we can even turn down the power of this light and able use nodes make the emissive half it's not as bright and then for our size of the light which is the intensity of the shadow bring that up so it's a softer shadow and we're not gonna go over too much compositing again here since we need to get to the tripod shot but let's just quickly go over it so once we're happy with this compositing we no longer need this well one of these was a background so let's just get rid of one of these render layers and we don't need this so right now what we have is our footage the image sequence being undistorted again we calculated for lens distortion so now it's getting rid of the distortion so undistorted and then this is just making sure it fits the frame don't worry about this one we'll have this be the background and then in the foreground we're gonna have our render layers which is our monkey so right now we have two undistorted node sequences so here we have this undistorted footage and then the under layers is just undistorted by default it's just in our 3d viewport so we have to undistorted things stacking on top of each other and then to match everything together we're just gonna duplicate with shift D and then readest or it everything so distort so now everything is undistorted and then you distort it back and everything should be working so this goes into the viewer so that's what we see in the compositor going back to the first frame of course we don't see our monkey because we haven't rendered it so let's just make sure our settings are good so in film we have we have transparency I'm gonna go a bit of water here okay so we have transparency and then for our samples we can we're fine if it's grainy we don't care we just want to make sure that it works so two samples and then I think that's all we need because our colour management is set to standard yep and if you want to do filmic for the monkey you're gonna need to render it filmic and then have the background separate and then overlay them later as standard but we're not gonna worry about that so if we hit f12 unless I made a mistake let's see what we get so we get our noisy monkey and then it's gonna add in the background and everything is matching up as you can see if we go to another frame where we're now here let's render this frame 93 yep so the monkeys a bit cut off cuz that's where it would be spatially if we move the camera over there so I'm gonna call this a done shot you know you could put whatever you want in here but this is just camera tracking not messing around with your scene in 3d tutorial so I'm happy with that so I think let's do the tripod shot now for the tripod shot we're not going to do any of this monkey stuff just the camera track itself and maybe a bit of orientation so we can keep everything here I think is fine and then we're gonna open up the movie clip editor and this time track the other image sequence and this time let me get a big gulp of water so I can go we can just you know go through it if you haven't a tutorial yourself or if you haven't done any public speaking for the song you would be surprised at how fast your voice just goes but we're gonna we're gonna just you know power through it okay enough nonsense what were we even talking about we were talking about doing the other track so let's open up the sequence on the desktop tracking camera track and then finally the tripod sequence bring that in and go back to the first frame now a lot of the stuff is already set for us like the frame rate is already 30 the color management I don't know why this is open the color management is already set to standard so all that's good otherwise you need to do it yourself so again set scene frames now we're going from 1 to 200 nice clean number prefetch loaded into memory now I've already emphasized this but I just want to mention one more time this is a tripod shot because I'm standing still it's not really on a tripod I'm just holding it in my hands and going like this but it's in one stationary place and then just orbiting around so it's a different kind of solve and really all we're gonna be changing here is this checkbox right here but the tracking process is pretty much the same so I'm just looking for high contrast good trackers here and I think a lot of these are gonna blink in and out of existence since I moved the camera around so much but I do like this one right here and tripod is actually one of the good things about tripod is you don't really need to use that much a finer perspective the reason why is there's no parallax change because we're just staying on one spot so you wouldn't expect there to be any perspective differences so really you just want to use a location rotation scale which is what we talked about is just tracking changes in translation how the pattern rotates and if it's getting closer or further away and for this one actually there's no scale because nothing is getting closer so we can actually do location rotation so this is a case where you'd actually downgrade your motion model because it makes sense then it saves you time we can still enable normalize there could still be lighting changes and then correlation I still want to stick to point nine so location rotation motion model let's see how does put a tracker here go to the tracking window so we can actually see what's going on here alt s for the search box and this one I'd imagine is gonna be even faster than the last one Bowl C ctrl T so made it up so here I think we can get an extra frame out of this okay so I'm happy with that and we'll see if it comes back in so we can do a joint rec I suspect that it will yeah there it is that does it lasts long enough yeah it does so it's worth actually doing if it was only there for like three or four frames I don't know if I would have although objectively does what you want to do so make sure it's the same dot let's track backwards a little and then forwards with ctrl T ctrl L to lock this and this time I'm gonna really try to do this at full speed to show you how fast you can do this so track join track it's gonna make the commentary a bit harder but I think it's worth it so let's pick something in the break here something that looks unique like this one that has this protruding brick control T add another reference frame since it blinked out and just keep adding reference frames it does seem like there's a bit of parallax change again I'm not holding it on a tripod really it's just in my hands so there's supposed to be a tiny bit of parallax change which i think is what we're seeing here otherwise there wouldn't really be if it's perfectly stationary but I'm fine doing it this way let's lock that in and I do want to review this one over here just making sure the center point is relatively in the same area yeah everything kind of looks a bit wobbly but that is staying in the center so that's good and this time we're gonna use a fine to get rid of that issue let's do this right here track four now you're seeing tracking at speed just get a couple extra frames lock this in see if it comes back it does actually never even blinks out into first place we just have some margin issues so I'm gonna unlock this and then scale it down just get those extra frames and then once we're in the safety area we can scale back up and lock that in let's try to get one more in this area since it seems to be in frame the whole shot so with a fine let's do one here again we don't need to really pick dots or anything just anything with a recognizable pattern that you could track with your eyes and doesn't have any reflections or it's not moving like a biker or a leaf over here you wouldn't want to do necessarily it's always good to pick some stuff with some distribution in 3d so let's pick something in the background like the corner of this vent like that and track that we can get an extra frame here maybe not we'll just lock it and see if it comes back I kind of doubt it since I angle the camera down yeah so that one's done what else is in the background if we pick the sitchin yeah there shouldn't be any parallax so normally this box right here would kind of obscure it after a while after we moved the camera but since there isn't that much parallax this will always be visible so let's add a tracker here with this dark brick control T and especially on tripod shots it's really important to get a bunch of different depths and get that 2d and 3d distribution we've been talking about we can actually use a lot of these squares that seem to be everywhere that will make very obvious tracker markers take a bit longer but it is a good candidate lock that in and we should be getting pretty close to having eight throughout the whole shot I'm gonna go for another one of these like this one this is great for tracking because we these two lines like this that make it very clearly defined what we're tracking so that only lasts for 60 frames and it should come back we'll see okay it does so I think it was down and then two to the right let's see yeah down two to the right so wait for that to pop up and then add this in again make sure you're not selecting the wrong tile otherwise your solve will always be like 150 every time you hit cameras all track backwards and then go to where the send it off and track forwards again we're doing this at speed lock that in go back to where was visible shift click and join okay let's see let's go to the last frame and see what else we can pick up here I wonder if this twig is here for the entire shot that might be a good tracker assuming that it's not moving in the wind or anything we'll see about that yeah I think it's staying on there okay so we'll lock that end that made it pretty far what else I'm looking for tiny dots now cuz they are very easy well see if the motion blur is an issue for this one it's already very hard to see nope that worked out perfectly maybe we'll keep testing our luck on these see this tiny white dot in the background we'll pick that you get pretty good at detecting what would be a good tracker marker as you do more and more of this so if you're like oh how did you see that you're you're gonna notice it when you're desperate and need that camera saw you'll see it I'm in the hot seat so let's see what else let's get some stuff in the background here these bricks at least some of them are looking very distinct track backwards you know one issue I'm noticing LLC does this even come back yeah I want to show up issue I'm noticing is a lot of these trackers aren't surviving the whole shot I'm gonna do eat this one and it's not a big deal but it is nice to have trackers that last a long time and also we have nothing on the right side over here so that's not very for our 2d distribution so let's add something in a spot we can pick out again it's like that track Ford's okay I made it to frame 59 let's see if it comes back so it's this a very discolored brick the bottom-right corner of that okay so that is coming back can we pick it out I think is this we'll make sure to check again so track forwards and then track backwards lock that in so I want to make sure that it's the same one so we have this discolored brick that that's that's at the same height as this piece of the wood over here so let's see if that's the same that appears to be the same so we can shift quick join tracks and do we have eight I would believe it if we don't so I'm just gonna pick one more of these tile trackers maybe this one because they seem to be plentiful and pretty much a free tracker marker and a lot of them do seem to ask the holeshot my last bit of water this is gonna be precious very precious come on make it through the whole shot do it oh oh look at that it almost didn't make it but it's a survivor look at that it was really on the margin okay let's lock that in and then we'll try to do a solve it will tell us if we don't have eight active trackers there'll be an error message right here and I don't think we've ever ran into this issue but maybe we'll see the error message for the first time so hopefully that goes away in a second so solve and then this time make sure to enable tripod and then relatively everything is the same you see a lot of this key frame stuff is grayed out we're not gonna worry about that so with tripod enabled let's go for a camera solve okay three point seven six with tripod shots it's a bit different in that it's kind of okay to have a bit of a higher solve but really what's really telling is the graph we want to tell the quality we want to look at the quality of our graph okay so this is like it seems to be capturing our camera motion just not very well let's go for a couple more songs yeah so that's consistent and I wonder if the keyframe settings even matter what tripod they might not yeah it seems that they don't and there's probably some theory behind that because when it's doing its limited construction and then extrapolating that's dependent on looking at a set of trackers between the frames and looking at how they move in terms of parallax and when that doesn't exist because the tripod shots it no longer becomes relevant so it's okay to have a bit of a higher solve error here but ideally we want to minimize it so with refine we'll refine for everything see how that does okay now we're down to two and this graph is looking a bit more settled let's go for one or two more see if it's constant sometimes what happens here is it will actually change the focal length and the optical center that it's going for yeah you see it's doing tiny adjustments over here so sometimes they get something a lot better sometimes they get something a lot worse but after a while it tends to stabilize on this number apparently again it's okay to have something a bit higher here but we can do these same tricks as always see if we have any inconsistencies with our graph make that a bit bigger so these dips over here just mean that they just came into existence you see this tracker right here so it's going from zero to whatever value so this is an action and consistency but maybe the beginning of this is so let's try trimming and doing a solve without any refining anymore just so we can see if this changes anything is that worse okay yeah that's worse so you want to undo that and you just want to try this and see if it does better or worse so let's go for this one trim the end solve that is better okay so that's that's the case where it actually helped us and I'm expecting to find one or two more of these yeah what's up with this one over here is it because it's a weird tracker might be because it's going to the margin over here but I'm gonna cut this off and see what happens so trim that that actually worked so let's go even a bit further trim okay I'm happy with that and let's see if we can do any more correction before messing around with our weights I think we just messed with this one and we ran into an issue so let's not do that hmm okay so if you look into this you might be able to do a bit more maybe with this tracker specifically let's try one more round trim I think that helped I don't even remember what number was but let's say that we're actually done with this step and then we're on to the last step which is the weights which makes really bad trackers worth a lot less we've already gone over this so turn off the footage info so we can see all the errors and whoo yeah some of these are really bad some of these are 3.2 whereas some of these are are any of these under 1 yeah this one's 0.8 so we can do a lot of work here with the weights more so than with the normal parallax shot so let's actually do that so with this one we want to cut down the way to half and with anything that's like three points something that's really bad cut down the weight what else do we got three point three eight sounds good to me not good as in a good tracker but good to cut down and then you want to disable the Salak so we can zoom in closer okay a lot of these seem to be doing very well did we handle this one okay so let's go for a solve okay now we're in 1.6 so getting even better and let's just do one or two more rounds of Correction until we get down to like 1.3 I think I'd be happy with and again the cameras all kind of matters less because you're just gonna get a camera that's moving around so it's not gonna look like things are sliding around as much if you have a half-decent solve what else is doing not too hot this 2.4 it's pretty bad let's go for another solve okay 1.46 I did say 1.3 will see if I hold on to that promise my not this one we need to cut down a lot and it's just this refining process I think there is a script that I saw somewhere that does this automatically but I think it usually goes a bit too far where all these weights turn to like around zero which isn't very good because now you're not representing the shot the original shot that well and you want to retain some of that motion data so you don't want to get too extreme with this okay we're under 1.3 I'm happy if you look at our blue line there's a bit of inconsistency but it's relatively it's relatively flat so the interesting thing here is actually doing our orientation so with our 3d viewport oh yeah we have all this set up so let's actually get rid of all this I guess and add in a new camera and it doesn't really matter where it is it's gonna do the camera solve no matter where the camera is its independent of location yeah so once we're happy with the solve we can set up tracking scene and you see that this one's a bit different if we play this the cameras staying still but it's rotating around its location if we hit and four properties we can see that this location is staying still so that that's the important part here and in terms of orientation we're kind of missing the most important part here so I want to make sure we actually see this in terms of orientation or in terms of these trackers really you're gonna notice that they're all at the same distance from the camera it's actually creating a sphere around it and it's projecting those points on the sphere so all of these exist on a sphere of a certain radius around the camera which means that it doesn't really know the location of our trackers and it shouldn't because it doesn't have any parallax data so that's what makes a tripod shot very special in that these trackers don't really mean much in terms of their location because even if one's very far out and ones very close that's going to project them to the same distance since it just doesn't know with the information that's given now that doesn't mean we can't do a bit of with orientation so we can still pick you know initial position and orientation for this but it's just that it doesn't really matter where these are so there's no like origin floor plane or anything like that but if we go into this you see that this is sticking on very well just in a very different way so let's move this to a place that makes more sense like over here play that out yep that is tracking on very well move this down a little and you want to do this orientation manually I would recommend so it's kind of hard to tell but we're gonna set this rotation to make sense on this frame and then it's gonna move around top view might help here so what I'm doing is I'm just setting this camera to look straight ahead on whatever frame were on frame one ninety nine essentially the last frame two hundred and then it's gonna move around based off that which will make our plane kind of look like it's resting on the floor of course we still have the issue that it's looking like it's angled downwards and to fix that we want this view you need to rotate until it's looking right it might be even better to do this in the camera view so rotate on the y-axis until this is aligning up and then if we play through this I mean you can tell that the solve there even though it's higher than what we usually accept it's not as significant no matter what you put no matter where you put it in the C and even if we move this cube here it's gonna look like it's really attached to our frame and with in terms of compositing it's pretty much the same deal as always we have this background and it made a background layer for us and if you want to mess around with the shadow catcher you want to move everything to the same layer and it might have even messed with our compositing no it didn't it actually kept it as is but it's the same type of deal just that this time we don't have any parallax so my voice is officially gone now but we've we've done it we've gone through part four of the motion tracking tutorial series and very soon well could you hear that did that hurt to hear very soon we're gonna be doing object tracking which I know is what everybody is getting hyped about so that's the next part in this motion tracking series so I hope you guys enjoyed this I know is more of a repetitious type tutorial than what you're used to but I do think it's important to go through these examples so from now on whenever we're doing our camera solves or object solves which are gonna happen to be very similar you're gonna know how to do it at speed so my voice is gone I'm probably croaking at this point so I think I need to go check out patreon if you want to invest put your money into these tutorials for example this microphone that should hopefully sound better not my voice but this microphone sounds better this was due to patreon investment so it goes directly into this channel I think that's all I have to say my voice is gone I'm out of here I'll see you on the next one bye bye

Channel: CGMatter

Views: 37,025

Keywords: blender, 2.8, motion, tracking, camera, tutorial, matchmove, camera tracking, motion tracking, compositing, cgmatter

Id: epTx7iM4Lb8

Length: 56min 7sec (3367 seconds)

Published: Wed Jul 24 2019