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Blackmagic Fusion 8 Tutorial – Improve Green Screen Composites


Hello people, My name is Mohith and Welcome
to my first tutorial on YouTube. In this tutorial we will go over the topic of Keying in Blackmagic
Fusion 8. Lets get started. We have our source loaded in to the flow area.
Selecting the loader we will hit Shift-Spacebar, that will bring the Add Tool Menu and search
for Primatte, by typing the first few letters of the tool. That will add Primatte to the flow. we will go ahead and select the double view
icon, so that we have two viewers. To see the effect of Primatte, We will click
and drag the Primatte tool in to the Viewer 1. You cant see any effect ie, because we
haven’t changed any settings on the Primatte .
Click and drag the Primatte in to the second Viewer as well. Click on Fit. We will also click on this button to get the
Alpha view. Select the Primatte tool. On the Right hand side we can see the setting of
the Primatte. First click on Auto Compute. That will give us a pretty decent Key straight
away. Next I ll click on Clean background noise.
Select Box from here. Click and drag in areas where we need solid
black. ie the transparent areas. Now click on clean foreground noise. Click
and drag in areas where we need Solid white. ie, the areas that we want to keep. Now if you see here, we have a pretty nice
KEY. For the Spill Suppression we ll use this clip.
There is a lot of evidently visible green spill on our subject here, which will help
us understand the de-spill method better, as the results will be more evident as compared
to the previous clip. As earlier I have added the Primatte and I
have got my Key. Now there are two things
1. We have lots of green spill , around the hair, on her face and on the Reflective dress,
which we have to remove. 2. We have this tracking object which we do
not need. First we will get rid of the unwanted object
for that we will add a polygon mask by clicking on this icon.
Connect it to the garbage matte input of Primatte. Select the polygon and we will draw a mask
around the subject. Well that’s not the result we want.
Not to worry, go to settings click invert. That will bring our subject back and the unwanted
object is removed. Let us add a little bit of feather to the
mask. Now getting to the spill suppression, let us add a matte control node.
Connect the source clip to the background input of the matte control. Drag it to viewer
2. Go to spill, Select Green, because our background
is green. Push this Spill suppression all the way to
1. As of now we don’t get a satisfactory result. The spill method is set to rare. we will try
different algorithms, but I think Well done suits our purpose here.
It gives us decent result, but it can be better. If you compare our source clip with the de-spilled
one, there is a Luminance difference and I would like add that luminance back in to the
de- Spill. For that , first we extract the spill out
of our source clip and then add it to the de-spill.
For extracting the spill, we will have to subtract this from this.
To do that , I will add a channel booleans node.
Connect the source to the background and the matte control to the foreground of the channel
booleans. Change the operation to Subtract and alpha
to – do nothing. We have our spill extracted, which can be
added back in to the despill. Before that I will add a brightness contrast
node, so that we have more control. Take the saturation all the way down.
Add another channel booleans. Connect this to the background and this to
the foreground. Change the operation to Add.
That is what we get. I ll do one thing, Add the source to A and
this one to B. You can see that we have achieved similar luminance. Next step is Spill Replacement. First we will add a background node. Connect
the output of the background node to the output of the brightness contrast node. it will automatically
add a merge node in between. Change the apply mode to multiply. Now select the background
node click on this arrow, that will bring up the color wheel.
Drag the merge in to the viewer 2. Now if I move around in the color wheel, you
will see that the spill is replaced by the color I select. ok So, why is this Important? To show that, I will go ahead and connect
the output of the de-spill or the channel booleans to the output of the Primatte with
a merge tool. Now This is what we get. Let us also take the output of the Primatte
and connect it to the effect mask input of the merge. Now we have our Key along with the Spill Suppresion.
We will also add a background for our Key. which is an image I pulled out of google.
Our background has more Resolution, so I have added a Resize node to bring it to 1920*1080.
Fit. Connect the output of this merge to the output
of the background. Lets view it in the viewer. Now if I select the background, and change
the color to may be purple. You will see that the spill is matching this color. but this
region, it would have been better if we could get the Sun’s yelloyish color affecting that
region. So let us try and get the background itself
to affect the Spill. For doing so, First I ll add a blur node.
Connect the background in to the blur node. Let us increase the blur value, and connect
the blur in to the foreground input of the merge. Now if you see the spill is replaced by the
colors from our background. The make this effect more obvious i ll select
the brightness/Contrast and increase the gain value.
So you get to see what exactly this is doing. Get the gain value to the default. Next step is Color matching. From hereon we will be using the previous
clip. So this is what we have after the spill suppression and Replacement.
This is our background. For color matching we will go ahead and add
a color correction node. Now connect the background of the color correction node.
In the settings go to Histogram and click on match. Uhhhh …That is too much. Once again, two
things that we need to take care off. 1. We don’t need the color match to affect
the alpha region, so we will connect the output of the merge to the effect mask of the color
corrector. that takes care of our First problem. 2. We need to dial down the effect of the
color match. So we will bring this slider down, may be till there. Also increase the
smooth out correction curve. Next step would be Relighting. Though its
not a necessary step we can certainly use it for getting some interesting result. It will all depend on the mood and feel that
want to achieve in a shot. First we will add a bitmap mask. connect the
color correction to the Bitmap. Now add another bitmap to this. Connect the color correction node in to the
background input, change the mode to subtract. Right now we can only see a black solid.
We will select the move tool and move it like this. Now we have a mask for just that region
of our Key. To make it more interesting. we will feather
the mask by sliding up the soft edge. We will also go image and click on Frame to
get rid of that at the bottom. Now to the second Bitmap, We will add another
color correction node. Connect this to the background input of this
CC node. Lets view it in the viewer. Now if we move the gain , you can see what
it does. Let us go for a value of 1.1. You can see the difference that it makes.
To make this process more interesting, let us copy these three nodes Ctrl C and paste
Ctrl V. let us make all the right connections as earlier. Now select the second bitmap and click on
invert. Go to image and click on Frame again. Now select the color corrector. First click
on Reset all color changes. Then in mid tones bring the lift value down.
So now we have transitioned from here to here. Next Lightwrap and Edgeblur. We can certainly do it manually but here I
ll be using the Wrapper node. Hit Ctrl B to bring up this window and go
to macros. Double click on the wrapper. Wrapper is added to the Flow.
Connect the background to the background input of the wrapper and this to the foreground.
if we view the wrapper in the viewer, we have our background and the our Key combined. Let us change some setting in the Wrapper.
Go all the way down, click on output wrap only, for visualization purpose. Now let us click on use luma keyer, take wrap
size up. We ll keep this at default, Alpha gain down and the blend down as well.
So this is the light wrap we have. By clicking use luma keyer ON and Off we can see what
it does. Lets increase this effect. Click on Do Wrap 2.
This time we will leave this option off. Let us push the wrap size a long way up this
time. Bring this half way down. Alpha gain down and the Blend further down. Click on use color wrap, increase the saturation.
push the color wrap size up and bring the gain down. Next click on edge blur view edge for visualization
what we are doing. push this slightly up, this one a little down, up, Leave it at default. Increase the blur size. These settings are
self explanatory. you should play around with it to achieve the results that you are looking
for. Off output wrap only.
To see the effect of the wrapper let us add a merge node and make the connections. if
we drag these both in the viewer we can see the difference.
let us delete the merge node, we do not need it. For grading as you would have guessed, we
will add a color correction node. These adjustments are based on personal preferences and the
mood we are going for. I ll take the shadows to the bluish- purple
around there. The mid tones to the light yellow and the highlight towards the cyan. Let us also increase the gain value to 1.15.
In the mid tones get the gamma to 1.1 and in the shadows, get the lift values down. For further grading, let us go to Tools>Film
>Light Trim. Increase the value to 2.Yet again go to Tools
>Film>Film Grain. Tweak the settings to achieve the results
that we are looking for. there. Now if we compare these two, you will be able
to see the grains. Next we will add a Vignette. For that first add a color correction. Add
a Circular mask, tweak the mask. select the CC node and bring the lift value down. Drag it to the viewer. We need to change the mask settings. Increase
the feather and click on Invert. There we have our Final Result. So that is it for now, there will be more
videos like this coming up soon, So STAY TUNED!…. See Ya..

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