Auto tone, contrast, and color

show more Auto tone, contrast, and color provides you with in-depth training on Design. Taught by Deke McClelland as part of the Photoshop CS4 One-on-One: Advanced show less
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Auto tone, contrast, and color

In this exercise, we are now going to apply the three children of the blessed union of Levels and Curves, and those children go by the names, Auto Tone, Auto Contrast, and Auto Color. I must say not names that I ever considered for my own children, but they are commands and commands are special people. Now we are going to see how these commands just make mincemeat of the problems with this image right here, which is a good thing. We want to make mincemeat of problems. I do want to show you something else. I'm working wide screen, notice that. For those of you who are with me in Photoshop CS4 One-on-One Fundamentals, that gargantuan 12 chapter series that started you on your way, we are going wide-screen now that we are in the advanced series. But we are still not wide enough to accommodate this image and the palettes. So I need to press Shift+Tab to bring my palettes back, so I can see my Layers palette.

Notice that I have layers setup for Auto Tone, Auto Contrast, and Auto Color, so you can do your thing, but first I want you to switch over to the Channels palette right there. This is an RGB image, Red, Green, Blue, and that just figures because I captured it with a digital camera, the Olympus Stylus 1030 SW as I was telling you, and digital cameras have a habit of capturing RGB images, 99.999% of the time, or percent of cameras I should say will capture RGB images. There are a few exceptions out there. But we do have this RGB image and that means it's made of a channel of Red information, a channel of Green information, and channel of Blue information, and all three of these channels are essentially independent grayscale images.

And so if I click on Red, we can see that we have a dark red channel, not surprising because the image is very bright. Where Green and Blue are concerned, we have a Green and Blue color cast going right here. So the odd man out, if you have Green plus Blue, you are getting Cyan, the opposite of Cyan is Red. So Red is out of favor where Luminance is concerned inside this image, so it's dark. In other words, that's one way of saying dark I suppose. And then Green, very bright, overly-bright. So we have a lot of Highlights to work with but very little on the way of Shadows. I mean, basically no shadow detail, just Midtones and Highlights. And then same with blue, we do get a little darker in the shadow detail, but only slightly.

It's normal for channels to deliver different information. So for one channel to be bright where another channel is dark, that's fine. But for the channels to be this widely out of sync with each other, that's bad. Where we have basically no Highlights of any merit inside the Red channel, just Shadows and Midtones, and no Shadows inside of the Green channel, just Highlights and Midtones, that's a bad thing. And so we have problems on a channel by channel basis. Each channel is different. That is something that the Auto commands and Levels and Curves can take care of beautifully.

So the other commands like Brightness /Contrast, those functions, they are really looking at the full composite image whereas Levels and Curves are capable of taking a look at each channel independently, which is a great thing. It makes them that much more powerful. So what do we do? Let's go back to Layers. I just want you to see the wackiness that is this image. I am going to go over here to Auto Tone, and I'm going to click on that layer and I'm going to turn it on, so it's active, and then I'm going to go up to the Image menu and choose the Auto Tone command. Notice that it has a keyboard shortcut, no reason on earth to memorize these shortcuts, you're just not going to be applying these commands often enough to warrant keyboard shortcuts at all. So just choose the command, but I do want to say this first. If you have used Photoshop CS3 and you are wondering Auto Tone, that's a new command, that never existed before. It's just a rename. It used to be called Auto Levels, now it's called Auto Tone. It functions identically. So no difference compared with the old version of the command.

I am going to choose Auto Tone, and I get this. Look at that. Amazing, this is before and this is after. It was capable of fixing the image that beautifully that's stellar. We just went from a cloudy day, not only did it take care of the bad metering, that wasn't inherent, there is a function of me breaking the camera, it also kind of cleared up the date and made the weather better, which is fantastic of course. Now let's try Auto Contrast, really this is what you do. You just try them out. See how they function. And so all I did was I just took the exact same image and duplicated it three times onto independent layers. All right, so I'm going to go to Auto Contrast, turn it on and select it.

I am going up to the Image menu and I'll choose Auto Contrast, and in case you are wondering why am I applying static color adjustments instead of applying adjustment layers, that's because these guys aren't easily applied. It is possible to apply them as adjustment layers but it's not easy to do, and that's kind of pointless and sort of an absurd thing to apply, something so simple that really doesn't have any control associated with it as an adjustment layer. I am going to go ahead and apply Auto Contrast now to the static pixels, and it looks like this, so not much happened there. A very subtle change. This is before and this is after. Now you may wonder, well, is there some reason that these commands are in this order? Auto Tone first, and Auto Contrast, and Auto Color? Because Auto Contrast seems to do less than Auto Tone, and you will see Auto Color does more, so why isn't it Auto Contrast first, then Auto Tone, and then Auto Color? That would make more sense.

They are arranged in the order in which they happened inside of Photoshop. So Auto Levels occurred first. I think it was Photoshop 2.5 and then Auto Contrast came around, and I believe, I want to say it's Photoshop 5.5 but it may have been 5, and then Auto Color came around in Photoshop 7. So this is before the whole CS thing, and that's the reason they have just sort of sat there in the same order they appeared inside the software. Auto Tone will compensate for color cast, Auto Contrast will fix the contrast of the image, but it will not compensate for color cast. So it doesn't do a very good job where this image is concerned. Let's now take a look at Auto Color, turn it on, this is the Auto Color layer version of the image, and then I'm going to go out to the Image menu and choose Auto Color, and bang, that does a beautiful job. So not only did it correct the contrast, it also corrected the color cast, and it tried to neutralize the grays inside the image. So I'm going to turn off this Auto Contrast layer because it's no good.

It was not a good adjustment; and I just want to compare Auto Color to Auto Tone here. So I'll turn off Auto Color. There is Auto Tone in the background, looks good. Photoshop did manage to not only compensate for the contrast but also the color cast of the image, however it left the neutral areas, the areas that should be colorless grays. In other words, it left them somewhat bluish-green, whereas Auto Color was capable of making them neutral grays as we are seeing right there, and basically, making the scene every bit as good as it should be.

Now if you feel like, gosh, some sort of mix of Auto Color and Auto Tone would be nice, then because you set things up on independent layers as I have for you actually in advance, then you could go ahead and reduce the opacity of Auto Color. For example, I could say, you know what, let's change the Opacity value to say 75%, and press the Enter key in order to accept that modification, and just a slight interaction, so 75% Auto Color mixed with the remaining 25% Auto Tone gets us this beautifully mixed image here.

So I'm going to show you before and after by Alt+Clicking or Option+Clicking on the eyeball in front of the Background layer. So this is before, this is the original image, it was that bad, absurdly horrible this image was, I tell you, and now if I Alt+Click or Option+Click and then eyeball again, this is how good it is. I'm going to Shift+ Tab away those palettes. So again, this is before, I did that by reverting, by pressing F12, this is the after version of the image. Thanks to three little children, three little incredibly powerful children that when they work, if you apply them to the right kind of problem in the first place, work brilliantly well. In the next exercise, I'm going to show you how those commands function, just so that you have a sense of what's going on under the hood. Stay tuned!

Auto tone, contrast, and color
Video duration: 8m 1s 20h 57m Intermediate


Auto tone, contrast, and color provides you with in-depth training on Design. Taught by Deke McClelland as part of the Photoshop CS4 One-on-One: Advanced

Design Photography
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