[flow_default] Transcription: 01. Color Balance & Waveform.json

transcriptions/01. Color Balance & Waveform.json

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+{
+  "audio_file": "01. Color Balance & Waveform.wav",
+  "text": "Hi everyone, in this video I want to show you the entire process of color correction and grading directly in Blender. Some time ago I was working on the animation project and just because I didn't have After Effects installed on my workstation I decided to do the entire process in Blender and to my surprise it turned out to be much more efficient than importing, turn the Notes on and drag and drop our XR file. So as you probably know from the previous course chapters, I'm using the XR files because this allows me to store the exact render output in a single file. For example, if I was using the PNG or JPEG files, I would lose a lot of data and it would be really hard to work on the post processing in Blender on a file renderer layers and connect it like that. The composite node, if you're not planning to render the animation frames from this setup in the compositing, you can just delete it. I'm gonna now press the N key, hide the toolbar on the right, go to the screen corner, left click and drag to have another screen here and I'm gonna switch to the image editor. So now in the image editor I'm gonna click here and choose the viewer node. So this way everything that it's plugging to the final, to the selected viewer node will be visible here. In the image editor I'm going to press the N key and select the scopes here. So previously we've been only focusing on the histogram but today I want to tell you more about the waveform and a little bit about the vetroscope. So you can click here, drag down and have this better preview. with I'm gonna start with the waveform. So this image here Gives us an information on the pixels on our rendering going from the left to right So all you see here is the representation of pixels in this side of the rendering when you go here It's this side the rendering. And so I'm gonna demonstrate it later with one of the nodes. But to start, I'm gonna add color and color balance node. And now I'm gonna copy this node and just check, sorry, change the settings here. So I'm always starting with those two nodes and now I'm gonna start editing the first node looking at the histogram to know what's happening. So before we start we have to understand what those values mean in the color balance node and it's actually pretty easy to lift. Represents the bottom values of the waveform. Gain represents the upper values of the waveform and Gamma are all the middle tones. So as you can see, looking at the image, we lack of those brighter tones. They are only visible here in the windows. And if you'd like to balance the tones of the image, it's nice to have this waveform spread across all the ranges. It will, of course, vary between different images, but here you can see everything is kind of stuck to the bottom. So to fix that, all you have to do is just move this one slider and you can see this whole tone range is now spread it more evenly across the different tones. Now you have to be careful with using those settings because let's say I'm gonna slide those values down. You can see we're getting this flat line here. And if I hold the Ctrl key and my left mouse button, we can scale the waveform. So you can see we are now getting this line here. And that means all the dark tones, all those tones are now clamped to 100% dark. So let's say here on the left part of the image it's probably this area like this here. It's now 100% black. So in general you want to avoid those extensive clippings in your image. And when using this slider is like too sensitive you can always go here and just type the values manually. So I would say something like this is okay. And if we still feel that the contrast is a little bit off in the image then all you have to do is use the gamma slider. So we can do it like that and then move those brighter values a little bit up. So you can see just with those very, very easy tweaks, we are getting much more balanced image and it already looks like miles better than the default rendering. Let's now move to adjusting the colors. So when we look at the image, we can see there is a little bit too much red in the white color spectrum because our intuition tells us the ceiling, the walls are white, but in the actual image they are shifted towards the red. So how can we fix this using the waveform? Well, we have different options here. Normally I like starting with the parade and what it tells me, what it shows me is sometimes that you have a the It's virtually not visible in the darker areas, same with the blue, whereas the green is overrepresented. So we can use the parade view to quickly analyze the image and see how it looks like. And what's really great with using the waveform is no matter what's the quality of your desktop monitor, because on lower quality monitors, by looking at the image, you might not be aware if there is a color shift or or something wrong happening. Your monitor might be set up in an incorrect way and you might look at the image and feel that it's looking nice. But the other people who have different monitors, they will see the color like shifted towards red, green or blue. So what's great about the waveform, it always tells you the truth. So how it is in reality. And what you want to have in the parade view is the balanced look between all the channels. So basically what we had at the beginning was a pretty good result. I can just click on this color bar here and reset the settings here. Just keep the value as one and we'll have the starting point back again. So the way it looks here in the Parade Editor, in my opinion, is good. I can look at the blue channel and see the bottom values, so the lift values are kind of clamped, but it doesn't bother me that much. When I look at the image, I can try playing around with this color wheel and trying to maybe adjust the bottom color values a little bit but not too much. So if I move it towards the blue color then the blue channel will be untouched and the red and green will be changed only. So the color towards which you're moving will actually be unchanged. It might sound counterintuitive but it is how it works. So just look at the waveform right now when I move the dot towards the blue color, the blue channel is untouched and red and green are changing. So essentially, if I see there is a flat line here, I can either try editing the blue channel or bringing those two channels down so they match this. So to do this, to edit the red and green, at the same time, all I have to do is just moving this dot towards the blue channel. At this point, it's pretty hard to tell if the changes are for better or for worse, because there is also the RGB mode here. And this is where I try to work on the image the most. So when we look at the RGB waveform, we can see those different shades of RGB tones. And we can also see those white spots. So the white spots represent all the pixels which are completely desaturated. Since this is on the right side of the screen, I'm guessing it's representing this part of the image. And in general, what I find looking the best when working on the post production in Blender is having the white and black areas desaturated. So we are looking towards bringing those values into the white spectrum here in the waveform. And all those values like this, we just have to analyze them and see if the color channels are very much separated from each other. And if we want to balance the image, we just need to bring those colors closer together. So sometimes it depends on the image. If you bring those, so you can see this red, green, and here the muddy blue line. If we bring them next like to the same line perfectly align them then the pixels that are represented by those lines will be desaturated and that's also not what you're looking for like in every single scene for example here. I don't think it will look good but now enough talking let's see how we can do this. So since we can see those lines are here in the middle part of the waveform that means we can readjust them the best, the easiest using the gamma wheel here. I can see the red channel is up, the blue channel is a little bit down and the green is here. So maybe I will try to bring everything towards the green. So as I mentioned before, if I move the dot here towards the green color, the green channel will be the least touched by my editing and the other channels will move. So you can see the red channel kind of aligned with the green, but the blue is still offset. So I can just play around a little bit and I also need to look at the image itself because the waveform is a very helpful tool, but it's still just a tool and you always need to pay attention to the final look of the image. I'm gonna just play around with it a little and see what's the result. As I mentioned, we don't have to bring those lines together because then the image will get desaturated here. What we want is to decrease the distance between the lines. So there is not that much of a red color visible here. Now I think we are actually getting there. If I just move it too far here, we will get too much of the green tint. So I will try to look for something in the middle. And I'm actually pretty happy with this result. I can use also this second graph to adjust the colors. So when I have the lift gamma gain selected here, those three color wheels are editing the certain areas of the waveform. When I use the offset power slope, honestly, I never use the offset. I just used, I essentially only use the slope one. So the slope, it applies the color correction to the whole way for it, not to a certain color spectrum. So for example, if I increase the brightness of the image, you can see the upper values stay exactly as they are, as they were, the bottom stay exactly as they were and I'm able to move the color spectrum between the upper and bottom values. So you can use this slider, after you set up the tones here, you can use this slider to increase the general brightness or darkness of the image, as well as the colors. So you can see here, still the blue channel is a little bit off, so let's try to move this knob towards the blue. Maybe it will help, maybe not. But I think in general the image looks now much better. It's a little bit too cold still, but when we compare it to the original result and what we have right now, I think it's, yeah, it looks definitely better. So now one thing that's definitely off the natural look is the green color. As you can see the vegetation, it looks unnatural and artificial, but we can only edit the green colors using one more node and that's the hue correct node, which is very handy, but you have to use it carefully. So I within this node, you have H as v value. So we can change the value of each color, saturation and hue. What I'm trying to limit myself when working with this node is just the hue settings because when I always try to work around the values or saturation, I get some strange artifacts. So I don't know if it's me doing something wrong or it's maybe Blender not being perfect. This node system is pretty old to be honest. So yeah, just be careful when using saturation and value. And I usually just stick to the hue. So anyway, when you look at the hue correct node, you can see we have different color spectrums. So when I click on this dot and just move it down, you can see the green values in my image are changed so it's obviously too much and I just want to bring those green colors more towards yellow so when you move down you're bringing colors towards yellow when you move up it's towards the blue the colors so yeah all you have to do is just move down a little bit and I'm also not happy with the way the wood looks. I think it's a little bit too yellow so again we can just move this point a little bit down or up. I guess down is better and maybe try to readjust this tone. So also when you're working in Blender Compositor you can have as many viewer nodes as you want. So if you want to compare before and after, just copy the viewer node and plug it in one step before you're applying anything to your image. And then just by clicking between the two nodes you can compare the results. So I think it looks pretty, I mean the greens look much better right now, the wood honestly. It really also depends on the mood. Sometimes you just think it looks good the other day, you don't think that way. But I think in general the image looks definitely way better to what we had at the very beginning. Now with the hue changes applied to my image, I can always go back here and try to readjust something. So now even with the waveform hidden, I can look at the image and think, okay, do I like it or not? I think the shadows still are a little bit too cold. When I look at the black areas here or here or at the glass here, I feel it's a little bit too cold so we can play around within the lift values here and maybe try to bring a little bit of the red tint back if it doesn't work you can always play around with the Gemma which is the mid tones. I don't think we have to touch any of the highlights. You can always just try doing it. Actually, it looks pretty cool. So yeah, as you can see, the way the waveform is, as I mentioned, it's just a tool that really helps you understand what's happening within the image. It's a great tool definitely when you want to set up the tone balance in your image, so the bright, dark points and the contrast. But as for the colors, again, I always try to look at the parade view first just to be sure there is no like a huge color offset anywhere. Here I can actually see there is some blue offset down, but when I look at the image I don't feel it's something bad necessarily and then within the RGB when I look at the color lines I see there is a lot of distance between them I try to bring them together. Also one more thing if I look at the waveform and I see there are no white areas like this one's here then that means you definitely have to work on your image that means you definitely have to work on your image that that means you definitely have to readjust those white areas at least so they do not bear any of the color tint unless that's that's the effect you're looking for for example you want to apply a sepia photo filter or something similar on your image then yeah that's explainable but in a regular use always try to look for at least some areas of your image to be completely desaturated, especially in the highlights. Before we end this video, I still want to explain two things. Some people like to adjust the colors within the image using the vectorscope. The vectorscope essentially gives us the saturation values in the image. So theoretically, the more those black points are around the image center, the more balanced is the saturation within the image. But I personally do not always find this word correctly. So to readjust the vectorscope, I suggest using those two color wheels within the power and slope. So as you can see when I move this point, the vector scope spectrum also shifts. So sometimes you might try different approach to the color, to balancing the image than I did. You might try to bring the saturations to the middle here within the vector scope and then start working on the waveform. So for example when I do this you can see we get a very strange color behavior here within the mid-range and then you might use those the gamma node for example and the others to bring it back together but as you can see right now we have this clean white line here and the image gets kind of muddy so yeah again you always have to look at the final image in the end. These are just the tools that are here to help you analyze and understand what's happening and I want to close by showing you a method of analyzing a certain part of the image. So for example we want to see the waveform values of this ceiling area. So to do that, I need to add the box mask node. And if I just drop it here, you can see we're getting this white box visible. I'm able to move it using the values here. So let's let's change its size to something like this and now let's move it towards the ceiling and by the way we're gonna use the same setup in the second part of the video to create the vignetting effect directly in Blender. So what I have to do now is to add the color mix node, change it to multiply. Where is it here? Yeah, and also I'm gonna add the RGB curves here and darken the external parts of the image. So yeah, we do something like this. And now here in the waveform, you can see we only get this little part visible and it's this exact square. If we move it left and right, you can see it's also updated here within the waveform. So again, we can now we can see the exact distances between the colors within this area of the image. So if we think, well, the blues need to be closer to the red and green channels, we can go back here and readjust whatever we want. Right. So now we get much cleaner preview of what's happening, but again in the end you will still have to work on the full image just to see if everything is proportional in terms of colors. So yeah, I'm gonna leave it here and catch up with you in the second part of the video where we are gonna add just the visual effects such as vignetting, glare and distortion.",
+  "language": "en",
+  "confidence": null,
+  "duration": 1450.16
+}