welcome back to another episode of our camtrackar master class in the first episode we took you
through how to use our free virtual production studio app for ios camtrackar we demonstrated
some of the powerful features for onset real-time previs including chroma key and 3d model import
and in this tutorial we're going to show you the next step how to take that footage and composite
it inside of hitfilm you can find the project files in the description if you'd like to follow
along so let's get right to it at the end of the last episode i talked about getting the files from
camtrackar off your ios device you can see the individual folders for each recorded take we did
on set there are two shots we're going to look at for this tutorial the first involves adding
a 3d model to the scene and the second focuses on the green screen aspect for this first shot
all i need to do is drag the hfcs file from my camtrackar folder into the media panel and hitfilm
this composite shot has all of the tracking data inside of it so a camera will be created as well
as import the footage itself if i scrub through here you can see that the 3d grid is already
aligned to our scene the motion tracking is done and i can straight away begin adding elements into
my clip and it's as simple as that that's where camtrackar is really powerful it does the motion
tracking for you we don't have to worry about it now there are numerous different things you could
do at this point and they could all be their own vfx tutorials one common thing to do when you have
your scene fully 3d tracked is to add a 3d model we have several tutorials on this that go into
detail and since that's not the focus of this master class i'll just give an overview of that
process if you're using express you'll need the 3d model render pack when you import your model
you'll have a variety of controls to dial in the textures and the way the materials react to light
we tend to use sketchfab.com for high quality 3d models and mostly go with the gltf format
but hitfilm also supports obj fbx 3ds and lwo once your model is imported we can drag it into
the scene a quick way to place it directly on the anchor from camtrackar is to parent the model to
it then reset the model's transform properties you can then unparent it from the point if the
anchor point of the model is in the wrong place you can change that in the transform properties
this is important to have it properly sitting on the floor the model moves with the camera
correctly but it doesn't look too great select the model and go into the material properties
the environment map setting helps the metallic surfaces appear to reflect its surroundings
and ambient occlusion creates extra shadows in places like crevices and corners the other
important thing with compositing a 3d model is the lighting hitfilm has a few different types
of 3d lights and i'll create a few to replicate the lighting on set including the different colors
you can also place 2d effects on the model layer just like a picture or video
to further composite it into the scene
remember to turn on motion blur when you're ready to export now let's focus on the green screenshot
you've seen before you can do the majority of this workflow in either hitfilm pro or express
but since i'm going to be using the custom light flares effect later i'm going to do this in pro
i'll follow the same process import the composite shot and the footage will come with it i'll also
import a rendered background created using unreal engine 4. this is made possible by importing the
camtrackar fbx into unreal if you're not sure how to use the camtrackar data in other programs like
unreal and blender don't worry we'll cover that in the next episode the first thing we need to
do is mask out any areas of the footage that aren't green screen because they'll stay there
even after we key out the color using the freehand mask tool draw a shape around your subject in the
controls panel activate keyframes for the path position rotation and scale now go through your
footage and create a rough garbage mat around the subject adjusting the mask to always include them
this is not an exact roto of the person just enough to remove anything that isn't green screen
once the mask is finished we can remove the green screen i'll use the chroma key effect
if you're in express and haven't purchased the add-on you can use either the hue and rgb
key or the color difference key use the eyedropper to select the green color and adjust the various
controls to remove it if the edge has a little bit of a halo you can use the erode expand slider to
push the edge in the pre-blur slider can help if your edges are looking too crunchy but they're all
right here next i'll add a spill removal effect to get rid of the slight green cast and then we can
begin matching the color between the two plates compared to the snowy cold environment oli looks
quite warm here first a color temperature effect to cool him down but this makes the shadows very
blue almost purple so i'll use a hue saturation and lightness effect i can go into the blue and
magenta channels and turn down the saturation and even shift the hue to be a bit more cyan
to push the color in the right direction i'll use a curves effect
lowering the red channel will add cyan and i'll add a curve in the green channel i'm doing this by
eye to match the color of the background you can also use curves to brighten or darken the footage
in the final example i added a lens flare in the distance since we already have the tracking
data this is super easy to do realistically first create a point change it from 2d to 3d
use the controls in the viewer or position in the controls panel to move the point to where it would
be in the 3d world now i'll create a plane and add the custom light flares effect to it
right-click and change the blend mode to add or screen
open up the options and choose a preset you like or make your own i went with
dark of the moon which is inspired by the anamorphic look of the transformers movies
in the hot spot position set the center to zero zero and set it to use the point
the final grade layer is where the composite really comes together because these effects get
applied to the entire scene i'll use the curves effect again to tweak the colors to be just right
then add some stylization effects like chromatic aberration an anamorphic lens flare bleach bypass
to change the colors lens dirt to add a bit more texture when the light hits the shot
as well as some film grain to make it look less cg obviously the scene was composited with this
background in mind but if we wanted to swap it in with something like this star wars corridor
i would just have to make a few adjustments and tweaks to better fit the composite
now that you've learned how to film a scene with camtrackar and then composite in hitfilm you might
be interested to learn how to use the data to work with other programs like blender or unreal
engine to create the 3d backgrounds that you saw in this video we'll be covering that in the next
tutorial so be sure to subscribe and ring the bell so that you get notified of when that video goes
live if you have any questions leave them down below and we'll see you all in the next video