Today I show you the Curves effect.
You use it to adjust brightness and contrast and even to color correction.
Hello and welcome to this new Google lesson.
In this After Effects tutorial I'm going to show you the Curves effect.
This effect is a really important effect because you can do so many different things with it.
It can be used to adjust basically any aspect of your color.
You can use it for color correction to make your image lighter, darker, add contrast, whatever.
It's really the essential effect for color correction.
Let's apply it to our composition here. We have already prepared a layer with our footage.
Now we want to adjust its color using the Curves effect.
We just drag it here onto the footage.
In the previous lesson you've seen that you can apply such effect to adjustment layers.
But if we only want to affect this one layer and this is the only thing we have here,
you do not need to keep it on a separate layer but can also put it on the layer itself.
The Curves effect consists of this one graph here, this line.
You can click on it and modify it to adjust your image.
The aim of this tutorial now is that you need or I want you to understand what this line means
and how you need to change it to get what kind of effect.
You do not just play with it without really understanding what is going on
but really to understand what is happening here.
The exact same effect also exists in Photoshop.
I think there it's more easy to understand first.
Therefore let's now quickly switch to Photoshop.
I have unfortunately only a German version here.
In your English version you could go to Image,
Correct or Color Correct or something like that.
Graduation Curve is called in German.
So something was curved in it and then you have here this curve line
and what I like better in the Photoshop version is that you see here this color gradient
and this color gradient effectively explains you what is going on here.
What this line says is how the color values or the lightness values of the original image
are mapped to values of the final result.
So for example this point here of the curve tells that 50% gray of the input
maps to or results in 50% gray in the output
and 100% white in the input becomes 100% white in the output.
On the other hand if you want to make your image now darker
so you do not want to have 100% white to get to become 100% white
but it should become darker you can move this point here down
and if I do this you can immediately see the image becomes darker
because 100% white in the original image is in the result this gray value here.
With the same idea of course you can also move this point
and say 100% black should become something like this gray value.
100% black this input should become this output here
which makes the entire image effectively much lighter
and this is a way to make elements lighter or darker.
Of course if the image should be brighter here you seem to also lose some quality or so.
Brightening the image in that way doesn't really look very natural
and this is because if you make black this 80% gray or something like this
it will effectively erase everything that is,
or you have no really dark pixels in your image anymore.
Therefore a much nicer way to make it brighter
is to say I take me here an additional point by clicking
and here also another additional point maybe like this.
This now says something like I still want to allow very dark.
100% black still remains 100% black
but if you go a little bit lighter it becomes here in the result a lot lighter.
In other words you do not forbid 100% black completely
but you just make it occur less frequently.
Brighten your image by choosing a curve that makes here in this darker part
maps the colors of these darker parts to here brighter colors.
This more or less dark gray becomes here already 50% gray which is much lighter
but you see that this looks really more contrasty
than if I simply move this here up.
So the image becomes also lighter but it by far not looks that good.
Talking about contrast you can see if I disallow here the very white elements.
So it's like white maps now to 25% gray and black to 75%.
In total the image didn't get brighter or less bright
because I made both the dark elements less dark
and then the light elements less light.
So in total I've just lost a lot of contrast.
But what you usually want is of course to have more contrast than you had before
and how can you do this?
I mean you cannot move this point here in the opposite direction.
I move it below because 100% black cannot get more than 100% black
and 100% white cannot become more than 100% white.
So what you therefore can do is to say okay 100% white must stay 100% white
but the other light areas of the picture these ones here should become even lighter.
So make the light portions even lighter and the dark regions of the image.
So this half should get even darker.
So if you have such a kind of S curve it says make the bright regions brighter
and make the dark regions darker.
And this in total results in more contrast.
So you can make this less subtile or more subtile.
So now we have more contrast than before.
If you swap the S curve say you want to make the dark elements lighter
and the light elements darker you can see we lose contrast.
So this image looks much less contrasty.
So the normal S curve, more contrast, this S curve here,
so this inverted S curve, less contrast.
Okay I hope this gave you a brief idea of how you can modify contrast
and in general how light your image is.
And now the next thing I want to show you is that you can do this also
for individual color channels.
For this let's switch back to after effects.
So again here this curve has exactly the same meaning.
So you can see now I make the very dark elements much brighter
and everything very bright here becomes basically 100% white.
So I brightened my image quite a lot.
And if I instead now do here some kind of S curve for example,
so such an S curve will increase my contrast
and sorry this S curve will decrease the contrast
and this shape like this, this S curve will increase my contrast.
And now I do not want to do this for the entire image.
So I click these points and move them away to get rid of them.
But I now want to influence individual color channels.
And this can be done by choosing here instead of RGB.
The red, green or blue channel independently.
So I can for example say I want to have more green in my image.
So what do I do?
I make the green channel more light.
So I brighten up my image by making everything more green.
Now you can see really everything becomes more green.
If you want to say the light regions,
the bright regions should get greener
and the other areas not,
make sure that this lower part looks more or less like a straight line.
And now you can see the dark regions here
have not much influence of the green,
but the light regions here and here are much influenced by the green.
Now you can compensate, can say for example,
okay let's say we want the dark regions to become blue.
So we take the blue channel and make it more in the dark regions.
And in the light regions it should not have so much influence.
Here we brightened up so we made the blue more visible in the dark regions.
Now you see that the dark areas here become bluish
and these areas are still tinted more green.
You can even reduce this here more.
And now you subtract effectively blue from the lighter regions,
which makes the lighter regions now become yellow.
So of course this does not yet look like a really artistic image,
but I hope it gave you some idea.
I hope you are able now to interpret this curve here
and understand what it means.
And again if you just want to change the brightness of your image,
adjust the RGB curve.
Of course you can do this here still on top.
Say now I wanted the entire image to be brighter,
or not as bright.
And go to the different color channels
to really modify the color and the look of your image.
Okay, that's it for this Guru lesson.
I hope you enjoyed it.
And my name is Matthias for mamoworld.com
and I hope you join again for the next Guru lesson.
