Join Deke McClelland for an in-depth discussion in this video Radius and tonal width, part of Photoshop CS4 One-on-One: Advanced.
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All right gang, let's review. We have this image right here called Tropical pathway.jpg. The Background layer is active. We go up to the Image menu, we choose Adjustments, we choose Shadows/ Highlights. Just a couple of sliders is what we see, so I'm going to turn off Show More Options for a moment. We'll just see these two, Shadows Amount, Highlights Amount. Just horrible defaults settings here, creating this dreadful effect that we're seeing on screen. So I would go ahead and take this Shadows value down to 30%, better, and elevate the Highlights value to 30% as well, to drop the highlights a bit. It looks okay, but as I say has Shadows/ Highlights written all over at this point.
I don't like that. I can mitigate the affect of the effect by turning on Show More Option. The reason this is just screaming Shadows/Highlights, I'm going to go ahead and zoom in on this a little bit, is because if you look closely you can see these weird edges sort of showing up around the steps and around other details inside the image. Let me see if I can point out a few. Notice this shaded portion of the railing right here, and notice this darkness right there, how there is this abrupt darkness at the beginning, and then it tapers off and becomes less dark, that is a function of Shadows/Highlights.
Detecting this edge and sort of scrubbing into the edge, a little bit, but not going all that far into it. All right. So we can disperse the effect a little bit, so that we don't have these weird edges showing up. It's another one of things where you can take a look at the image and go, yeah, this is it, this is exactly where it's happening, or you can just take any entire image at a time and go, something is wrong here. That's the impression it creates over time is just like, ha, this doesn't look write. All right. So turn on the Show More Options checkbox. Now you've got Tonal Width and you've got Radius for each of these options, for Shadows and Highlights. So Amount is just how much lightness you're adding to the Shadows and how much darkness you're adding to the Highlights. Tonal Width is what is Shadows and what is Highlights.
So in other words, at 50%, we're treating 50% of the image as Shadows, and then of course down here for Highlights, we're treating the other 50% of the image, that's 50% lightest colors in the image as Highlights. They actually drop off of course. They drop off gradually over that 50% range. But if you wanted to incorporate more colors into the Shadows, then you would increase Tonal Width. If you want to incorporate fewer Luminance Levels into the Shadows, then you would reduce the Tonal Width here. I'm going to take it down to 40%. That might require a little bit of an increase in the Amount value, which I think it does. So I'm going to take the Amount value for Shadows up to 40%, and I'm going to leave 30, 50 for Highlights, because that looks pretty darn good. You can play around with them if you want to.
Now, Radius is a little harder to understand, but Radius, it's that thing I was telling you about, that extra bit of darkness at the edge right there. It's because Shadows/Highlights is an edge detection filter, and this Radius value, which we'll see a lot when we look at Filter, such as Unsharp Mask and Gaussian Blur and those guys, Radius is all about evaluating and emphasizing or de-emphasizing the edges. So it's doing this sort of scrubby thing that's 30 pixels big, along this edge right here.
If you've got some tight details, like if you're applying this to a portrait shot, and you've got an iris or something that you're trying to brighten, then you want to bring this Radius value down. Otherwise, unless you've got some tight little detail that you're really trying to nail; and usually it's going to be an eye, usually it's going to be that kind of detail that you really want to narrow in on, but if you're looking at a landscape shot like this, you probably don't have that kind of detail that you're trying to isolate. So increase the Radius value. I would say you can take it as high as like 100.
I'll go ahead and take it up to 100 in fact. You want to make it big enough so that you're not seeing those edges anymore. There is a little bit of darkness still here. Anything that's left is going to be natural darkness that was actually part of the scene. So I'm going to take the Highlights Radius value up to 100 as well. If you pay close attention to what's going on inside the image, you're going to see the effects get dispersed. You can sort of safely ignore these last options. Well, at your peril actually, we should talk about them, but the thing is the defaults are okey-dokey. I would prefer that Color Correction by default was set to 0 and Midtone Contrast of 0 is good. But what that means is that we're not elevating -- Color Correction by the way is just Saturation, it's just another one of Photoshop's many words for Saturation. If you decrease the Color Correction value, you're going to decrease the Saturation of the overall image, and if you increase the Color Correction value, you're going to increase the Saturation of the overall image.
Now, this particular image, most images don't want any modification to Color Correction, in my opinion, most images want that left alone. This image, it's a tropical scene man, we want some heavy vegetation saturation. So I'm going to take this up to 60 and then Tab. Now, Midtone Contrast is going to emphasize the Midtones, which normally get kind of lost in the shuffle where this command is concerned. If you want less contrast, if you want to sort of send the Midtones away, then you would reduce this Midtone Contrast value right there, but that ends up creating sort of a leached effect that doesn't look very good.
Most images I think want a Midtone Contrast value of 0, but if you're feeling like you're losing a little bit of contrast there in those middle colors, those midtones, then go ahead and raise that value. You can take it really high, as high as 100. I'm going to take it up to 10, like so. Then Black Clip and White Clip, this is all about, if you also want to apply a levels adjustment on top of things. So you're trying to make your blacks darker and your whites lighter. So in other words, you don't quite have blacks or whites inside the image, then you would start clipping colors. You could raise this value like to 2%. Notice I'm going to clip away a lot of blacks now, which is exactly the opposite of what I want to do.
So I'm going to send that back to 0.01%, just leave it set to its defaults. I wouldn't monkey around with these too much, because they're just kind of weird. If you need to regain your blacks and whites, then you should use the Levels command to do it and you should use Levels before you come into the Shadows/Highlights command in the first place. All right. These are the settings I'm going to apply to this image. Click OK. Let's go ahead and zoom out a little bit, so that we can take in the entire scene, like so. Just to give you a sense of what we were able to accomplish, this is before, this is the original image. This is after, brighter, more vivid. We've got some more detail down here in the shadow areas, and a little less heat associated with these highlights on these railings.
Just to give you a sense of how that compares to the Curves Adjustment, I'll go ahead and press Ctrl+Z, Command+Z again; this is the original image now. Turn on low contrast. So that's what the Curves version of it looks like. Now certainly, I could have done better than that, but you know why, when Shadows/Highlights is so easy to use. So I'll turn off that layer and then press Ctrl+Z or Command+Z on the Mac to regain my Shadows/Highlights function. You can do that, isn't that amazing? This is the corrected version of the image. We have now discussed in great detail Levels and Curves and Shadows/Highlights here inside Photoshop. Tell you what, every once in a while I'll do this. I'll ask a question of the Peanut Gallery here.
Here is my question, would you like to see a Photoshop CS4 Color Adjustment series, that would just be devoted to the myriad Color Adjustment functions and we would take a look at not only all the adjustment layers that are available to us, all the Color Adjustment commands, but also a little bit of Lab, thrown in for good measure probably, and some Camera Raw correction as well, and I try to sort it all out. So I prioritize which things you really want to use and which stuff you can ignore, and that would be the series. That's what I'm thinking. It would be late 2009, mid to late 2009, but just let us know what you think.
I send you on your way to Chapter 14, in which we discuss Filters; those very filters that I was telling you are coming up, and we're going to learn how to sharpen details. Stay tuned.
Recommended prerequisite: Photoshop CS4 One-on-One: Fundamentals.
Download Deke's customized keyboard layouts and color settings for Photoshop under the download feature.
- Using blend modes, adjustment layers, and layer styles
- Organizing a layered composition so it is fluid and editable
- Creating and editing type in Photoshop
- Using blur effectively
- Using adjustment layers to add color
- Combining layers into a clipping mask
- Working with Camera Raw