So my last episode was all about making the
perfect node tree and this caused quite a stir
in the comments. I had hundreds of comments from people
going where do you put halation,
where do put you glow, where'd you put your grain, why you
put in your grain there and not the
beginning, all this sort of stuff. But the most common
thing that kept coming up was where'd you
put noise reduction. And it made me realize I haven't
actually done a single episode about
noise reduction at all. I'm going to show you exactly where
noise reduction goes. I'm going to
show you two different examples actually because I don't
put it in the same place religiously on
every single program. I'm going to show you why I would
change where it goes in the no tree.
I'm also going to show you a couple of really good tips on
how to dial in exactly the right amount
of noise reduction. And to do that, I've been very kindly
allowed to use an actual BBC one
documentary that I worked on in June. It's called Tommy,
Jessop Goes to Hollywood. I'll put a link
to it in the description. And Tommy's brother, Will, is
actually the director. I've worked with
him a couple of times now and he's very kindly let me use
the footage from that to show you a real
world example. So let's get straight into it. So this is
the actual original project that I worked
on. You can see my node structure is very similar to what I
gave away in my last episode. And this
is a one hour BBC documentary. So let's have a look at how
many shots that would be. So looking in
light box, I've got all clips selected and it's 661, which
is very typical for a one hour documentary.
The reason I'm pointing that out is because I don't use
noise reduction unless I really have to.
I don't like using noise reduction. It's as simple as that.
If I filter this by noise reduction,
you can now see how many clips I've actually got noise
reduction on and it is 56. So it's less
than 10% of the program that's got noise reduction on it.
And you can see quite clearly some of this
stuff is very low light. This is a sort of fly on the wall
type documentary, a lot of run and
gun shooting. So you're obviously going to get scenarios
where the lighting is not perfect. So
that's mainly why there's noise reduction in there. So to
allow me to explain the different
techniques of noise reduction, I've chosen two very
specific clips from the documentary and
I've put them into a separate timeline. So let me just show
you what that is about. I've got a shot
here and just quickly scrub through that. And I've got a
shot here and they both have different noise
reduction properties and they're in different places on the
timeline. So you can see this one
is on node two and the previous shot, the noise reduction
is actually on node three. So I'm going
to explain why that is happening. So let's take this first
shot here and let's have a look at
what's going on. Now, just to show you a quick bit about
the color management that's going on here,
I'll go to my settings, go to color management. We're in
our regular DaVinci Wide Gamma intermediate
timeline color space and our output color space, Rec.709
Gamma 2.4. We're using CSTs for our color
management. Okay. All documented in that episode last week.
I've got one on the end here. This is
taken as DaVinci Wide Gamma to REC.709 as always. And our front
CST is our camera profile up to DaVinci
Wide Gamut. And the camera profile on this one is Panasonic
V-Log. Okay. So it's Panasonic camera.
What I want to show you first is how it looked, but with
the CSTs on. So it's not the log image.
I'm going to show you it's in the correct color space and
you'll see what's going on. So I've
just got a wipe here. This is the image, as you can see,
it's really underexposed. And so the
first thing I had to do was lift it using this node here.
Okay. That's a lot of lifting to do in
there. Because it's underexposed, you've got noise and I've
had to lift it a lot. So this is why I've
put the noise reduction after this node in this instance.
Okay. Normally I would have it after the
CST straight away, but this one needed so much lifting that
I've actually put it in third. I
wanted to lift the image up first. Now, if I switch this
noise reduction off, you will see how much
noise is in here. Let me just zoom in a little bit for you.
I'll zoom in 200% and you can see a lot
of noise in here. Okay. So let's have a look at what I did
for this shot. I'm going to put it back
to fit. I'm going to bring up a couple of scopes here. So
we're going to have our parade and our
vectorscope going on. And let's just switch that on and
off. You can see quite clearly the noise,
even in the scopes. So what I'm going to do in this is I'm
going to reset that noise reduction.
I'm going to build it from scratch. So on your scopes, make
sure that you don't have this
selected. It's a low pass filter. And what that does is
filter out noise on the scope. So we want
to see the noise on our scopes is our first tip. All right.
And then what we're going to do is come
over to here. So we've got our motion effects. So this is
just selected from here, this row here.
And we've got two different types of noise
reduction. We've got temporal noise reduction
and spatial noise reduction. Motion blur on the end here is
just in that category. It's not noise
reduction at all. It's just a, it's literally motion blur.
So sometimes it can help disguise
it, but it's not part of noise reduction. So temporal noise
reduction is looking at forward
and backward frames in time. So what it's doing is taking a
single frame that you're on and depending
how many frames I select here up to five will depend how
many frames forward and backwards.
It looks at changes in the shot, thereby
determining what could be noise. Okay. Now,
once you go above three into four, five, your system
literally will grind to a halt. Okay.
It's really, really slow performance. I've got a really
fast Mac here. And when I go into four
or five frames, temporal noise reduction, my system pretty
much grinds to a halt. I generally
start at two and I often will just stick out to two frames
forward, two frames backward.
So the motion estimation type is faster is obviously going
to give you a faster rendering,
but slower results. And we always want better. We always
want the best results. So no point in
putting that on so faster at all. And the motion range here
is saying how much motion is actually
in the shot itself. So if I just put this into the loop
play and then we just start playing,
there's not actually a lot of motion going on in the shot.
So what you're doing is helping the
temporal noise reduction know how much movement should be
in a shot. So if you're doing a whip
pan, obviously that's a lot of movement. Okay. So we'll
just put that to medium. So there's not
actually any noise reduction applied yet because these
figures here, luminance and chrominance,
are still set to zero. Okay. By default, these are linked
together. So as we start moving up,
we start introducing noise reduction and
you can see that's going much softer already.
And let's take it back off and we can see the noise. Now,
one thing I do with this is I keep
an eye on the scopes. All right. So watch, this is our RGB
parade. So it's the red, green, and blue
channels. And this is vector scope, which is our
saturation. And I'm going to unlink these.
So the first thing we do is dial in temporal noise
reduction in the Luma channel.
And let's just look at our scope and see what's happening.
So as I move that, you can see there's
a point at which, if you look around here, there's a point
at which it takes out the noise and then
it doesn't do anything anymore. So that would be a good
point to start at. You just find the point
where it kicks and then just come back a little bit. Let's
have a look what's happening with the
chroma. Okay. There's a little bit in the shadows there as
I'd expect. Okay. So just down in the
shadows, that is being affected. Okay. But not so much in
the highlights there. So somewhere around
about there. So let's leave that set for there for now. The
motion here is, this is helping with
aliasing and artifacts that you might get on the image when
temporal noise reduction is applied.
So you can adjust that higher or lower amounts of motion.
And the blend is obviously blending it
back to zero. So if I have that back to on a hundred, I've
actually effectively taken the
temporal noise reduction off. All right. Let's have a look
at spatial noise reduction. What spatial
noise reduction is working on a frame by frame basis. So
it's much more accurate than the temporal
noise reduction. It's literally analyzing the image and
it's trying to keep as much detail
as it possibly can. So it's a far more intelligent noise
reduction. But again, this is much more
processor intensive. So you've got your faster mode. We
don't want to work faster. Okay. We want to
work at least better. The radius is the amount of softening
or blurring, if you like, that the
spatial noise reduction is going to apply to the image. So
we want to keep this as small as
possible. So start with small. If you need to build it up,
we can go higher. So next we've got
the threshold for our spatial noise reduction and Luma and
Chroma are actually locked together.
This is because we're in better mode. You need to go to
enhanced mode in order to make them run
independently. Now, a quick tip here is that if you go up
to the effects, you've actually got
noise reduction as one of these open effects. And the
reason for that is it now works in the edit
page as well. So it needs to be in this column. So you can
grab exactly the same settings that
you've got here in your open effects. Let me just type in
noise and see if we can find it. There it
is. I'm just going to put it onto a blank node for the
minute. So you can just see the menu,
but what's nice with this one is if I go
to spatial noise reduction and go to better,
I can actually separate luminance and chrominance out. So
if you need to do that, but you just want
to work in better and not enhanced, you should use it using
the open effects. And in fact,
sometimes I get better quality from the better mode than in
enhanced mode. So it's worth playing
with both. The main reason I'm not using it as an open
effects all the time is because I'm on the
advanced panel and it's really, really quick to dial in
noise reduction on the panel. So what we're
doing now is just having a look at how much temporal and
how much spatial to put in. And
ideally I want to be working with spatial a bit more than
temporal. So I try and get them
to about a half split. So whatever I've got going on in
spatial, I'll try and sort of work on
measurements around about half in the temple. Don't go
exactly half, but somewhere around that
sort of ratio. So we've been using our parade and our
vectors go to the minute. If I just switch
that on and off that node, we can see it's definitely
reducing noise reduction. And let's
just zoom into the image. Let's have a look at what's
really going on here. It's his face that
is concerning me quite a lot. And here we want to make sure
that that doesn't look noisy. If I play
that in a loop. Okay. You can see without noise reduction
on it really did need noise reduction
in this instance. Okay. I avoid it like the plague, but I
did actually need it here. So let's just put
it back on. And I just don't want to go too heavy. I don't,
it's a little bit of a soft shot anyway,
but I don't want to overdo it. So let's just dial in a
little bit more spatial threshold
and just see what we can get. Okay. Now the
second tip I've got for how much to dial in
is coming away from the scopes. So again, we just check in
that it's actually affecting it.
Okay. That's not really affecting it much there. In fact,
if I take my temporal threshold down a bit
more, let's see if I can actually reduce it better using
spatial threshold. Yeah. There's a little
bit coming in there. So if I put
my chroma there and my luma there,
I'm just playing around with these. But what I'm going to
do is switch to a different mode. And
if you go up to your highlight tool and press A/B, what that
does is show you what you're doing
just on that node. Okay. So if I switch all my noise
reduction off, let me just do this brutally.
There's nothing appearing because we haven't actually done
anything. So let's go back and
dial in our settings again. We're going to go to, we're
going to go better. We're going to say
at medium, and we're just going to dial in just luma. And
there we can see what's being affected.
Let's put a little bit of chroma in there and let's go to
our spatial. Let's start with better
and small. And we're just going to dial it in. And what I
want to do is keep dialing in,
but protecting the edges of his face. Okay. So the main
features, we want this noise here taken out,
but we don't want to be in a position where we're seeing
like this. This means we've got very heavy
noise reduction going on. So I'm just going to dial that
back again. And I'm just going to go until
we can just see his face and I'm going to knock it back a
little bit. And just by default, we seem
to have got, so that's 27, 28, so half that would be about
14. So we're a little bit less than half.
Let's just punch in a little bit more of this then. Again,
half is just a little rule that I've used.
And let's punch that back a little bit more, switch the A,
B off, or sorry, switch the highlight off.
And let's have a look at how much noise reduction we've got
going on there. So it's done a really
good job of cleaning up the image, but this is looking far
too false now. It looks a little bit
plasticky. So I'm going to dial it back. We could use blend
here, but I'd rather actually
dial back the amount of noise reduction than blend it back.
So something like that. So let's have a
look at with it on. So obviously we need to have it on. It
looks much better. This is far too
distracting for the viewer. I will put it on. It's doing a
good job of clearing up here and here.
Okay. Let me have a look at the whole image and press play.
All right. So that to me is looking
much better than that. You've got to always just put it on
and take it off. Just check that you're
actually improving the image. We could add grain and
sharpen and things like that to bring a little
bit of that sort of grit back. I've got it on the end here
after the CST. So I tend to work with my
grain in rec 709. And if I just switch that on and off, you
can see it affecting the scopes,
but let's just see what it's actually doing to the image.
Yeah. It's just putting a little bit
of texture back in just to show you my settings on that. If
I go to effects, I've got a grain
strength increased. And if I'm my advanced controls, I
normally bring down the highlights a
little bit. I don't want as much grain in the highlights as
I do in the shadows and mid tones.
All right. So that's that shot done. Now what I'm going to
do is move on to the second shot and
I'll look what's going on here. So this
shot, let me just show you the whole thing.
My noise reduction is on node two. And the reason for that
is if I just command D that's log,
obviously, but the exposure was actually very good on this
one. It just happens to have picked up a
bit of noise. So if I disable that and play through, the
noise on this one is actually in
a certain focused area and it was just a little bit
distracting. But if you look at his jumper
and look at the camera, even we can see noise in there.
Okay. Can you see it? And there's noise
here. Okay. And I just found it a little too distracting.
So I don't want a lot of noise
reduction on this. I just want enough to take the edge off
that. So let's put the noise reduction
on and play that through. And that's much better. It's
cleaned it up. So what I've done with the
noise reduction on this shot is I've isolated the shadows
into the mid tones area and I've kept the
highlights out of noise reduction. So I don't want any
noise reduction on his face. His face is
looking great there. It's just the jumper and the camera
that I really wanted affected. So to do
that, I used a qualifier. Okay. So before I reset this
qualifier, have a look at Tommy's face here.
Okay. You can see it's got really good detail in it. And if
I reset this qualifier, you can see
that it's gone far too smooth. Okay. It doesn't look quite
as natural. So let's rebuild the
qualification that I did. I used a luminance qualifier and
I'm going to switch on my highlight.
I don't want to be in A/B mode this time. I want to be in
this mode so I can see what's going on.
So I'm going to use the luminance qualifier here to protect
the areas of highlights. So just bring
that down until it goes in. Yeah. So we're just keeping his
jumper exposed noise reduction,
the camera here, and obviously we need to soften that off
or it's going to look really quite abrupt.
So something like that. Maybe I just knock that back a
little bit. So I'm trying to concentrate
on what I'm doing and explain at the same time. Something
like that. Let's have a look at what
that looks like. So I'm going to take that off. I'm going
to enable and disable. So there we can
see the noise reduction is nicely taken out his jumper and
his face has been protected. Okay. We
just got a little bit going in there, but let's just play
it through. Always play noise reduction.
You really want to play it. And if you're struggling to
play this in real time, what you can do is go
to playback, go to render cache, say user, right-hand click
on here and say node cache on. And then
that will now render. So if I play that through, it's going
to start rendering. It will go blue
once it's rendered. There you go. So now I've got real-time
playback of that noise reduction.
And anything I do after that, this will stay rendered. If I
do anything before it, then it
will need to re-render that cache. Okay. That's a
disadvantage of doing the nodes too late in the
timeline. So take a look at this video that's appearing
here. If you want a better breakdown
of my perfect node tree, this is the node tree I use on
this BBC program as well. Look after
yourselves and I'll see you in the next episode.
That was definitely a 10 out of 10.
Oh, wicked.