Today we're gonna be talking
about the differences between log footage and linear footage
when it comes to grading, and why just adding contrast
and saturation to log footage usually isn't enough
to get an accurate image. Let's get undone. [offbeat music] ♪ Gerald Undone ♪ ♪ He's crazy ♪ What's happening, everybody?
I'm Gerald Undone, and I perceive the world
with 18% grey. So, I already made
a previous video demonstrating how to match the colours
from different cameras, and also how to manipulate your
curves to take the log footage from different cameras and
turn it into sort of a neutral, accurate standard. And while
that video was well-received, many of you asked if we could
take a more beginner look at log and how to correct it
a bit more easily. So that's what we're gonna
do today. And for the more advanced colourists out there,
I ask that you excuse some of the oversimplifications that
we're going to use in this video in order to keep this video
a bit easier to digest. So I've got a few samples
loaded here into my laptop, all shot on the Sony a7 III
with different profiles. We've got S-Log2, S-Log3, HLG3, and then
the Creative Standard, full contrast,
no picture profile mode. And for each profile, I shot
this chart here from DSC Labs, so thank you to them.
Big fan of the products, they're the same company that
sent me the Xyla 21 that I used in the dynamic range tests
in those recent camera reviews. And this here is one of their
CamAlign charts, which are fantastic because of this
11-step crossed grayscale that you can see here, which makes
it really easy to see what these log curves are doing to your
image, which I'll show you in just a second. But if you're
somebody who's interested in making LUTs for money,
or just matching your cameras more precisely, I highly
recommend a chart like this to dial in your accuracy.
OK, let's look at the samples. OK, so as you can see here,
I've got a bunch of different samples all the way across.
The first group is just S-Log2 at different exposures, and then
S-Log3 at different exposures, and then two--
we got three HLG3s, and then this is
the full contrast linear one. This is what we're going
to start with, 'cause I want to explain that 11-step crossed
grayscale thing, which you can actually see on the waveform.
Let's make the waveform a little bigger here. So if we take a
closer look at this “X” pattern here, we can see what we're
looking for when it comes to a complete linear image,
which is that each step-- although this isn't perfect--
but each step, generally, should be about
the same distance, and that it should form
almost a straight, you know, 45-degree angled line
in both directions. And you can see that here
on this chart-- because from light to dark and dark to light,
that's why it forms the X-- and then each one of
these 11 steps is a value, with them both having sort of
a middle grey in the middle over top of each other. And
that's why this chart is handy, because now when we look at one
of the log shots, we'll be able to see how they differ
quite a bit. So this is good. This is a finished linear image.
This is when, you know, people are adding contrast and
saturation to their log footage. This is what they're trying to
achieve. OK? But this will have less dynamic range if you
shoot this in-camera like this, which is why we use log
in the first place. Now let's jump over to
our S-Log2 image here. Well, first of all,
we can see not only is the image very squished down
on the waveform, it occupies
much less of the waveform. But as we increase in exposure,
because often you'll hear, “I like to expose log one
stop over, or two stops over,” so I went through those as well.
Because when we're just down in the shadows here, this
whole "X" is below middle grey, so it doesn't look that bad.
You would still suggest that each step looks like
they're about evenly placed, but you just haven't really
expanded that waveform yet. But if we increase
the exposure-- so now this one is two stops over, I believe--
then we can start to see how it curves off
above middle grey there. Where the steps below middle
grey-- so this one, this one, this one, and this one--
all have a lot more height to them on the waveform, if you
will, than the ones afterwards, especially the last three.
They have, you know, barely any height at all compared to
the first three. And this is-- you're starting to see
that log shape now. The distance between
these values is not the same as the distance
between these values. And that's going to bring
us to, sort of...basically, the fundamental problem with,
you know, “quick grades” of log. Now, something to keep in mind
is that when we're talking about colour, nothing is
sort of true across the board. So not all logs are the same,
you know, there's things like C-Log1 and C-Log3, which are
already kind of contrastier, and maybe these rules
don't apply so strictly to them. And then there's stuff
like S-Log3, which we can pull up a sample of that here.
Let's jump right over to the four stops over S-Log3.
And you can see that one's even more squished than S-Log2.
And that sort of “squishing” is what we're talking about-
compacting data down, which gives you the most potential
for dynamic range, which is why something like 10-bit log would
require a lot more bits linear in order to create the
same amount of dynamic range. That's why there's math
conversions for that purpose. But I'm not trying to bog
this video down with that. Basically, if you want
to have more dynamic range and you're stuck in 10 bits,
you need to use a log curve, otherwise you're going to
run out of steps real quick if every step is evenly
spaced out like in a linear, like we saw in this last
one here. But the advantage of the linear stuff is that it
looks great right out of camera because you're occupying
the full waveform, so you have a nice
amount of contrast already. And we're gonna talk
about contrast a lot during this video. So, contrast from
this sense is basically taking the image, taking this squished
“X,” or whatever it is that you're shooting, a face--
and spreading it out across the image, across the values,
across the luminance values, or, in this case,
the height of the waveform. And when it reaches
down lower and higher, you're going to get darker
blacks and brighter whites, and it's going to have more
contrast, right? You guys know this already if you've ever
edited a photo or anything. The issue is that when people
do quick grades in NLEs, which-- I've seen a lot of YouTubers
comment on this lately. And I'm not throwing any shade
here. Their images look great, and I'm not criticizing
anything, but I have seen people evaluate the colour
and the tonality of a camera by saying, “Here's some log,
and I just added some contrast and saturation.” And I've also
seen some problems on Twitter lately of people asking
why is it when-- like, "Here's a quick grade I did.
What's wrong with these reds or these oranges? All I did was
add contrast and saturation.” And I hope that we're going to
explain what happens to those reds and oranges, and what
happens to your face when you just add a little bit
of contrast and saturation. So if you think of contrast
as sort of pushing things away from the middle...if your middle
isn't right, and you already have sort of, like, a curve
at the top, no matter how far you push it, you're not
gonna be able to get it right. So let's do one of those
and find out. First, let's add contrast to our linear image
here, which is an easy contrast. And I'm using Resolve, but it's
pretty much the same principle if you use a contrast slider
in Premiere, or Final Cut, or something else. Only difference
is that Resolve has a pivot, which we can also look at if
you're new to Resolve and wondered what pivot's all about.
So let's jump down here to the contrast slider. And we're
just using this one node here. So I'll position it like this,
so we can see the actual image, our waveform, and our contrast.
And I'm just gonna jack the contrast way up. Now,
see how things are getting pushed away from
the middle point there? So we have our middle grey,
and things are-- the space between these ones in
the middle grey is increasing, and things are getting more
squished here and there. That's what contrast does.
And if you look at the image, we've got really, really black
blacks, and now we're losing a lot of variation between
the whites here. We don't have that same sort of
nice gradation there. If we hide this and look at it,
now we can see clear steps between our grayscale,
which is what we wanted. We already had decent
contrast to begin with. But now, let's just adjust
the contrast back down a bit, and then adjust the pivot so
you can see what happens there. So let's increase the pivot now,
and you'll notice that now the midpoint is shifting down.
And if we go the other way with the pivot,
now the midpoint is shifting up. So if we had the pivot really,
really low, and then increase contrast, you see how
our middle-- our little middle of the “X” there is getting
higher and higher. But if we had the pivot
all the way the other way and we increase contrast, you see how
the middle point is going down. So pivot is almost like
positioning where you're going to favour-- who's going
to get the more information? Is it gonna be the shadows
that get more information or the highlights
that get more information? So let's load up an S-Log2 image
here. By the way, if any of you are having trouble, saying
“OK, this is all great and he's showing an X and he's showing
these values on this chart, but what does that have to do
with grading a real scene?” What you need to realize is that
every one of these steps here is the same, in essence, in terms
of contrast and luminance value, as something else in
the environment. So there's skin tone patches here, and
they'll have a similar value on the 11-step grayscale as
something else. So this whole scene you're looking at right
here could be represented by these steps on the grayscale.
And if you had a camera that, say, had 11 stops of dynamic
range, this is essentially what you're seeing, and maybe
your face is here, or maybe your face is here if you
have a darker complexion. And then, maybe, you know,
this is your sky. And then maybe this here is, like, the shadow
in the background. So it all applies, even if you're
not seeing contrast on a face. But we'll be able to apply it
so that you can see it, and, obviously, apply it to
your own footage and it'll work. But even looking at my face now,
you'll see that I have shadows, and I have a broad tonal range
across my face from, like, highlights to shadows. And
something I noticed about those YouTube things that I was
questioning, where I said on Twitter and on YouTube, is that
I'll find that often when they do just a quick contrast and
saturation to a log image, that their face will often lack tonal
variation. It might look nice, the image might look good,
and their skin might look nice and even and everything, but
that's what I'm talking about, is that they're only allowing
a certain amount of information for their skin, rather than
having it go across a whole, you know, wide range
of tonal variations. And that usually comes from
not positioning log correctly in the waveform, based on
not respecting the fact that it has a strong curve
to begin with. So if we look at S-Log2 here- this is S-Log2
exposed correctly. Which, by “correctly,” we mean
according to the manufacturer's standard of setting it to,
like, 32% or whatever it is for middle grey. We can see
middle grey is way down here, at, you know, that mid-30% zone.
Now, when we apply a LUT from the manufacturer, which I
have over here. I've got, um... I've got the one, actually, for
S-Log3. Let's do S-Log3 instead. So this is S-Log3.
Pretty similar. You expose this one to 41%
middle grey, so that means you want to target your middle
grey node there to go about 41%. And let's throw on
this LUT here, which is from S-Log3
S-Gamut3.Cine to 709. Now, if we throw that on,
now we can see that the waveform was expanded to form more of
that “X” that we were talking about, and the steps are a lot
more even. But you might think it's still a little bit dark.
The issue is that not all LUTs necessarily respect the correct,
you know-- they might say expose to 40%, and you
put it on and you find it dark. So depending on where
you're getting your LUT from, they might want you
to overexpose. For example, a LUT that I like a lot
is from Paul Leeming, but he wants you to overexpose
your image by a few stops. So if I jump over to Leeming
LUT Pro II, and I have the one here for S-Log2, and
we dropped it on this image, which is quite
a bit overexposed... Well, now we get a complete
image there. So, obviously, his LUT wouldn't work
on the 32% exposure, but it works on this overexposure
one here. And again, we get a really nice “X” with pretty
even steps all the way up, and that lets us know that now
this image has been sort of linearized, and the log curve
has been accounted for. But now, let's say
we want to do this ourselves. We want to do a quick grade with
just contrast and saturation. So let's go to this middle
one here. This is S-Log2, about two stops over, which puts
the middle node rate around 50%, so right in the middle, which
you think would be the easiest one to just apply contrast to,
based on what I just showed you with linear. I said,
“just throw up contrast and it pushes to the edges, then
you'll get a full image,” right? Let's try that. Now, as we
start to push the contrast up, you'll notice that all
that really happens is the log aspect of this
image is being accentuated. So we still have much bigger
steps below than we do above, and it's still curving off
like a log curve. So maybe we should
adjust the pivot, right? Keep in mind that not all NLEs
even let you adjust the pivot, so the idea of just adding
contrast in Premiere is probably going to make a worse effect
than even what we're doing here in Resolve. So now let's adjust
the pivot, so we can hopefully bring that midpoint back down
to about the middle... Well, OK. But we still are
getting that kind of log thing in the highlights, and we're
still not making it look like the linear image. Let's see what
our target is over here again. So with linear, we had a perfect
“X” all the way up to just over 90%, and down to
probably about 6% below. So let's see if we can reproduce
that again with contrast. So we'll add some more contrast
to try and raise it up to 90%, and then we'll try
and get the pivot there... And as you can see,
we've got this really strange... [chuckles] curve now, where it's
almost like a weird S-curve, where we're losing information
in the shadows and in the highlights, and we still
don't-- it doesn't look at all like our linear image. And
if we look at this full screen, I would say this image is too
punchy, and yet we're still not even really hitting, like,
the full range of what we could occupy,
even in Rec. 709. This would be what
I think people do that would be passable, and then
they would add saturation to it, so let's do that too.
Let's, um...let's-- let's cool down the contrast a little
bit. Because something else is that contrast affects
the intensity of a colour to your eye the same way
that saturation does-- not the same way,
but it also affects the intensity of a colour. So if you add way
too much contrast, and then add your saturation in,
it's going to be way overkill. So let's put the saturation--
we'll put it afterwards, 'cause people always say “contrast
and saturation,” but whatever. Uh, generally with log curves,
I find, in Resolve saturation, you need, like, 75 to 80.
That might be too much with the amount of contrast that we
have. But we'll add to 75 there. And let's take a look
at that image. So then we could say, “OK, this
image looks...somewhat finished. It's-- it's got contrast,
it's got enough saturation, it's punchy, it's finished.”
And this would be what I think people qualify as
a “quick grade” when they go to look at the
colour accuracy of a camera-- or, I find this in reviews--
often people will say, “I added contrast
and saturation, and now we can evaluate
the colour science.” You cannot, because the luminance of
these colours is incorrect. And that's one of
the issues that happens here. The easiest way to see
this on the waveform is, you see the colour chips-- you
can see, you know, the yellow, and the red, and the green.
You can see how high up the waveform they are. If we
switch over to, say, this one here, we can see that they
fall in different positions. And if we switch to the
Leeming LUT, which actually does a really good job with colour
accuracy, let's take a look at the relationship between this
yellow patch here and the green, and then the cyan, and then look
at the one that we just made. Our yellow is way up here. I don't even know where our cyan
is, and our blue is way down here. So we're not mixing our
colours well. And if we jump back and forth...even though
this one's not as contrast-y, so let's go ahead and add some
contrast to the Leeming LUT version to try and get a
similar kind of intensity going. If we switch back and forth
now, look at that colour shift. So look at these swatches--
this one, this one, this one, and the ones below as we switch
back and forth-- look at the way that they shift. The luminance
of them that's changing, and it gives it such an
extreme difference, because the human eye is very sensitive
to luma changes like that. So, that's another issue
with why you can't just do contrast and saturation and then
evaluate the colour of a camera, because your
luminance values are way off. OK, so before we jump
into how to fix that, then, I just want to show you HLG
as well, because that's another thing I get asked about a lot-
how does HLG fit in this? Because it's half log,
half linear in a sense, right? That's why it's a hybrid log. So
if we look at these HLGs here-- I got this one, I've got this
one, which is about one stop over and then two stops over,
which is about as extreme as you can go with HLG. And you
can definitely see a bit of a log curve there
at the top of the HLG. But when
you're not too overexposed, it definitely represents
a bit more of a linear look than the full log curves. So
the question, I guess, would be, can you just add contrast
and saturation to HLG? Well, let's give it a quick try.
So, for this one, you actually don't need to add
a lot of saturation to HLG. And we haven't talked
about saturation knowing how much is enough, but I'll
do that for you in one second. So let's add a little bit
of contrast here... and, you know,
we'll adjust the pivot. OK. So we added
a bit of contrast. It's probably not bright enough,
because of the exposure for it, so, you know, we can increase
the gain here to sort of brighten it up a little bit...
and give us-- let's see what that looks like...eh. Looks
like a pretty decent image. Now let's go over to this one,
and we'll apply a LUT on it. Again, Leeming LUT's got one
here that's pretty good for HLG. So we'll see what a fully
corrected image should look like, and we can
bounce back and forth. So...not terrible. Again,
our image, I think, was a little bit underexposed. But
you can see that we were able to achieve the result quite a bit
better with just contrast with HLG than we were with
full log. And this is kind of what I was saying, that not
all log curves are the same. And this also supports the
idea that I recommended earlier, that HLG-- like, a long time ago
with my videos-- is that HLG3 is probably a profile that'd
be easier to use for people than log if they want something
quick, because those quick grade principles definitely apply
a little bit easier for HLG. There are still some
colour space conversions that need to be done but that's what that
previous video was all about. Now, when it comes to
determining how much saturation we need, which I just
said we'd talk about... If we change this to
the vectorscope instead, we can see the colour swatches
and them approaching these target boxes on
the vectorscope. And there's a couple things you can do here.
If you don't have a chart in your shot, so you don't know
if your colours are falling in the correct zones-- by the way,
this lets you know that our own HLG that we did is not
exactly that colour accurate. Let's look at the Leeming
one...much better. They're all falling in the boxes. But
what we can do is look at our skin tone, if we have skin
in the shot. And this is our skin tone line, and you can see
the different skin patches here. Generally, for fairer skin
tones, like, I would say mine, and in this image here we can
see that they're referring to the lighter skin values--
you'd want them to come up this skin tone line, which is this
one here, about-- I would say about 40% of the way up.
And the darker your skin is, the less high up
that line is gonna go. But if we combine all
this information now, and... what does it mean that-- how do
we do it if we're not gonna do it with contrast and saturation?
I think that we can use all these mistakes to figure out
a fix. And I'm gonna go down to the curves here, and what
I'm gonna try to do is recreate, as best I can,
this linear image with S-Log2 by just adjusting the curve. I'm
going to do this really quickly, I'm not gonna try that hard
on it because I don't want to waste too much of your time, but
I'm basically just going to try and get our midpoint there
to fall around that 512 point, and then I'm just going to
adjust the curve until the steps look like they're occupying
a similar height for each step. And if I see an area that
looks like it's not too even, then I'm gonna come in and
just add another little point on the curve and fix it. And you do
need to be careful doing this. If you add too many points, and
if your positions of the points are too sharp, then you'll end
up with weird extremes, where, like, the colour
resolution might break apart and you'll see, like, weird
bands that you don't like. So try and be
not too extreme with it. Keep it somewhat conservative. And...I don't know. Something
like this. Again, I don't want to spend too much time on it.
But you can see, if we jump back-- we'll just take a quick
peek. There's the linear one. There's the window of the curve.
It's pretty close, right? And if you were watching those colour
bars while I was adjusting the curve, you probably would
have seen them shift position. So now we do still need
to add saturation. So let's go into our second node
there, and we'll add that... I don't know, 75 saturation in. And now you can see
those colours. If I just undo and redo,
you can see them get their saturation, but based on their
luminance-- if I hide this one and then put it back, and
hide this one and put it back, you can see that there's more
at play than just saturation. Let's take a look at
our vectorscope, and... I would say, yeah, we're pretty
good. We're hitting probably around 40% for
the bulk of our skin tones, our red is right there,
we've got nothing outrageous. And at this point is where
you would need to correct for the fact that often, logs might be using
different colour primaries. You know, maybe 2020 instead
of 709, or maybe they just have, you know, a certain flavor to
them, that they like to favour certain things and you don't
find it accurate, or you can't match it with other cameras.
That's when we'd go in and do the other steps that I mentioned
in the previous video. Now at this point,
if we wanted to, we could go in
and add a little bit of contrast if we felt like our image wasn't
punchy enough, or we wanted to, you know, get a certain vibe to
it. But we should use it more as like a finishing touch
that makes the image a bit more, you know, a bit more punchy.
But also keep in mind, you might then have to roll back
your saturation a little bit, because, again, contrast--
as I can show you here if I add a bunch-- will make your
colours look a lot more intense, as we just saw, so you
might need to dial back your saturation in order to make
that work. But...this will be up to you, but we should use
it more as a finishing touch, is what I'm trying
to say, rather than a way to correct log footage. Now, if we do switch back
and forth between this one and the linear to sort of
see how we did, we can see that our “X” pattern is pretty close. Our colours aren't exactly
the same, even though I would say the intensity of
the colours is pretty similar. And that's because I corrected
the colours of the log image where the standard has its
own flavor of colour, which, you know, isn't exactly accurate
if that's what you're going for. This is standard. You can
see it kind of has almost, like, a hue twist to it, where ours
is a little bit more accurate. And the most important part
is the gradations and finality between the different ranges.
So if we look again at the linear image, we can clearly
see distinct separations between the white and the different
nodes of grey all the way down to the black. And if we do this
on the image that we corrected with the curves,
we still have that. Where, if we look at the one
that we did with just contrast, I think that we have a lot
less separation between these high values, and that's usually
what I think creates that sort of plastic skin with very
little tonality in the skin. It's that kind of “squeezing”
of the highlights that is still kept
if you only add contrast. OK, so, before we jump
into some Twitter questions, I wanna give you just a couple
quick practical demonstrations. Because I know so far this
has been highly theoretical, and it might not be
that useful if you're like, “well, what am I supposed
to do on set--" [laughs] "--if I don't have, you know,
one of these charts or whatever? How am I supposed to
line up my Xs or whatever?” I can give you sort of a quick
little range of something you can do with your curves to make
it work, or what you should be looking for. I'll show you sort
of roughly what you have to do with the curves to make this
work. So if you have a log image that's overexposed, you're gonna
want to grab the curve probably-- generally, you want
to grab it around where your midpoint is. So if your midpoint
is around this 60, 70%, you're going to want to grab it
up here, and you're gonna wanna pull that down...and as you can
see, that will give you sort of that “X” back. Doing this will
put you in better shape to add just contrast and saturation
if that's what you need. This is what happens
if it's overexposed. You need to kind of, like,
invert the log curve. If you have a completely--
you know, neutral exposure, which would be, say, maybe this
one, where you're right at 50%, then you can try going
for a little bit of, like, an S-curve style, but you'll
find that your midpoint will still need to be adjusted
in order to make that work. So you're going to want sort of
an S-curve like this, where the midpoint is still
brought down a little bit, because once you boost it
up enough based on log, squeezing everything down,
this will give you-- now, this is for, like,
a 50% middle grey type of curve. Then let's do one if you
expose by the book. So with S-Log2,
you might be at 32%. Often you'll find these logs,
they want themselves 32, 35, 40, somewhere in that zone, usually.
So if you're at one of those lower exposures, you can see
already, just from this histogram, that we're all
the way down here. So we're gonna look where we are--
we're in, like, that 30% zone. We're going to grab further down
on the curve, and then bring that up to bring up the entire--
well, our entire “X” pattern, which, again, represents all
the values of our scene. And if we want to boost
our highs even more, we can, you know, try and like,
finesse this curve up here as we bring this up. And you'll have
to kind of adjust the roll-offs so that it's not too
extreme for you. And then, again, your midpoint's
gotta be adjusted, but you gotta be gentle with this because
you're doing such a boost. But if we jump between these
two...other than the fact that you can tell that I achieved
this exposure difference using f-stop, because our background
is different, we can see that we actually have a reasonably
similar image between these two. But look at the two curves.
So, exposure when you're low, you make a curve like this.
When your exposure's high, you make a curve like this. If
you're somewhere in the middle, you're gonna make a kind of
S-curve. And then for all three of these examples, you go in and
add, like, a 75 saturation. And then you'd have to add
a third node for fixing the colour inaccuracies. And
then those three things together would comprise sort of,
like, your correction LUT. That would be your LUT. And then
after that, again, you can add more contrast. So let's say that
we did our colour corrections here. Then we could add a fourth
node, and then we could add some contrast if we wanted to make
the image a little more punchy, and then finesse our saturation
again to make that work. OK. Again, I hope that
that information was helpful. I don't know how long this
video's been running for. I was gonna do this as a livestream
originally, but I thought that might take even longer. So
I'm gonna jump over to Twitter, because you guys had some
questions when I said that I was gonna do a video like this.
So let's just check and see what some of your
Twitter questions were. And it looks like our Twitter
questions are gonna be brought to you by... lawnmower sounds.
I don't know if you can hear them, but if you can,
I apologize. But we're just gonna motor on through. So
there's this question here from Jake that asked about why
Canon colour science-- you know, can you not just make that
with other cameras to match the Canon look? And the answer
is yes. Between that last video and this video, I think I've
demonstrated that you can definitely, you know, make
anything look like anything. Some are harder than others, and
some logs are more finished than other logs. But if you have
the time in post, colour science isn't really that important.
I would say colour science is only important if you need
to work quickly and you want a look straight out of camera.
Then you should probably prefer the camera that gives you
the look that you like because it'll make your life easier,
especially if you're gonna shoot like that last clip
I showed you, which was the linear standard
full contrast one. That's when colour science
will play the biggest part, because that image is already
complete. So...choose a camera that-- if that's how you're
going to shoot, choose a camera that has a complete image
that you like already. A question here about bitrate.
This is a good question that comes up a lot- how important
is bitrate as a factor? Generally, the answer is
not really. You only really need enough bits in order to achieve
the image. Beyond that, bitrate is more useful for, like, when
you compare-- you're comparing 100 megabits per second versus
400 megabits. Usually that's the difference between All-Intra
and an IPB, which is about, you know, editing, performance,
and that kind of thing. It's not really gonna make a big
difference in terms of colour. A colour value is still a colour
value. In that case, bit depth is a lot more important.
I wouldn't worry so much about bitrate. I would worry
more about bit depth and chroma subsampling and colour
resolution, which you do need a certain amount of data
in order to achieve, but once you've achieved that sort of
level, having more bits doesn't give you better colour, in a
sense. Hopefully that's helpful. There's a couple questions
in here talking about correction LUTs. So definitely,
if you get a new camera and you want to shoot log, I highly
recommend that you go to the manufacturer's website and see
if they have a LUT available. Those ones that I was using from
Sony came from the Sony website. When I made that video about
Canon before, I used the one from Canon's website.
The Leeming LUTs, however, those are third party LUTs
that he makes in order to make different cameras match
together, because Sony's LUTs don't have to match Canon's
LUTs. They're not working together necessarily, right?
And then there's also ACES, which is a whole 'nother thing.
But, basically, yeah. Go to the manufacturer's website
and see if you can get a LUT, drop that on, that'll do a lot
of the work that we just talked about today for you, and then
you can just do those contrast and saturation adjustments
because the correction of the curve, making it from
log to linear, and fixing your primaries, that kind of
thing, that would already be done for you. So this is sort
of in lieu of a LUT, but if the manufacturer has
a LUT that works for you, definitely get that. Something
to note, though, is that you can still use the same principles
I showed you on the curve if you shot your image wrong
for the LUT. So if you shot your image too bright for a LUT--
I can show you this right now-- or too dark, you can still use
the same curves to reverse what you did to make the LUT work.
For example...let's go to this shot here, which is
too bright for the Sony LUT. If I go to the Sony--
this is, like, I think, like, a two or three stop over--
if I pop on this Sony LUT here, that image is out of whack.
Look at the waveform. It's still, like, way
up top here and everything. But now we can reverse that
curve that we're seeing here in our curves to make the image
make sense. So, again, look where the midpoint is. It's
about 768, so like 75% area. So go up here, grab it, pull it
down a little bit until your midpoint starts to make more
sense. And then you still get the benefit of that LUT.
All those corrections are there, and we just sort of scooped
down our waveform to compensate for that. So again, still using
the manufacturer LUT, but now we reversed our overexposure.
And if we were underexposed, which I actually have
an example of, let's go here... I actually just used the S-Log3
LUT on S-Log2. So don't do that! [laughing] Because your
colours won't be right. This is an S-Log3 image
that might be a little bit underexposed. Let's drop down
and see-- yeah. We're a little bit underexposed. So now we'll
do the opposite. We'll grab down here a little bit, and we'll
boost that up. And then we can boost up our highs as well until
we get that image back to form that “X.” So you can still
reverse if you're underexposed or overexposed for a LUT.
You can still undo that over or underexposure with your
curves using the same examples that I showed you
throughout this video. And I think that's a good point
to end the video on, actually, because the lawnmower has
stopped. Perfect timing! Uh, I hope that this video was
helpful. Obviously whenever we get into these videos where
I'm like, “I'll just-- I'll just pop open Resolve and
we'll just ramble at the camera for 30 minutes!” I never know
if this information is gonna be useful to you guys at all.
But I hope it was. Thanks for watching. Let me know
in the comments if you've got some, you know, other questions,
or more confusion, and maybe we can try to bundle all those
together for a future video. But that's gonna be it for me.
I hope you found this video entertaining, or at least
helpful. And if you did, make sure you leave it
the old thumbs up, and consider subscribing
if you haven't already. But if you did not find this
video helpful or entertaining, try setting the playback speed
to 75%. Alright.... I'm done.
I'm sorry but he gets it completely wrong. It took me 10 minutes to realize he was talking about his rec709 gamma encoded shot when he said "linear", which is definitely NOT the same thing.
Going from log to a specified gamma is a simple mathematical operation that he's trying to recreate inaccurately with curves. This is definitely not the way to go, and the reason why LUTs exist in the first place. That's the whole point of 1D LUTs.
While this video has the veneer of seriousness, it is unfortunately as wrong as 99% of the color grading video you see on YouTube.
I usually only take advice from colorists I know have somemerits to them , don't wanna reinvent the wheel.
This is my exception. Gerald Undone is extremely technical youtuber that gives a great indepth explanation on how to access the basics of log grading. It's a very novice / beginner approach but understanding the basics is key in color-grading - and newcoommers might have a hard time getting the basics down due to the lack of good and easy to understand guides.
Gerald compresses a lot of information making it easy to understand and easy to test out your self.
Happy coloring.
I understand this is a very through explanation, but wouldn’t using Resolve Color Management or ACES be a quicker and very effective route?
Add in a color chart in your shooting and you’ll be all set for a great grade.
I feel like many youtubers dive into the smallest details and intricate ways of explaining a concept for what could be a 5 minute video.
I am a rather avid follower of Gerald too, but i don't agree with his procedure here. I prefer to do a Color Space Transform towards my target gammacurve (and colorspace), and work from there. Juan Melara has some nice fast tutorials on this.
This is the most info I’ve seen crammed into a single video on this specific subject. Super helpful! Upvoting to help others see this video!
Is this guy a professional videographer or colorist ?