Eliminate Harsh Tones and Improve Your Photos

How the Shadow/Highlight tool, History brush, and Dodge tool can enhance portraits

By Ctein Back to

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There are many kinds of f laws that make a photo scream “amateur,” but poor tone and contrast characteristics are among the most common. Amateur photographs often have a lot of midrange contrast, with tones in the highlights and the shadows pushed far towards the pure black and white. Faces suffer especially. They acquire hard lines and sunken eyes, aging a person 10 years, and excessive contrast can make a placid expression seem glowering.

Fortunately, problems like these can be easily fixed in the computer (unlike, say, awful focus or composition).

The Shadow/Highlight adjustment

Difficulties arise when you want to improve both shadows and highlights at the same time. You could do that with a curve shaped like the one in Figure 1. This kind of curve expands the contrast in the highlights and shadows but compresses tones in the midrange. Subtle adjustments can work well, but strong curve changes like Figure 1 don’t usually produce such attractive results. The midtones become so compressed and low in contrast that the print looks flat and lifeless.

By way of example, I applied this Curves adjustment to Figure 2, left. That photo preserves the original quality of an on-camera flash from the 1950s, but toning the harsh highlights down and bringing out the details that were lost in the shadows would give the photograph a more professional look. The Figure 1 Curves can do that (Figure 2, middle), but look at what happens to the midtones, most obviously in the tablecloth and faces. They look flat and artificial, as if someone just painted the tones and colors onto the photograph.

Photoshop’s Shadow/Highlight adjustment is an amazing (and complicated) control that improves the contrast and visibility of detail in both highlights and shadows. What makes it amazing is that it can do that without destroying midtone contrast.

Figure 2, right, shows what miracles Shadow/Highlight can work. The high- lights have more details, and the shadows are more open with better color and saturation than in the Curves- altered version, without destroying midtones. The faces and the tablecloth look just as lifelike and natural as they did in the original version, yet somehow the overall contrast of the photographs is moderated. It almost looks like it was lit professionally.

The Shadow/Highlight adjustment can do this because it doesn’t blindly apply curves changes to the entire photograph. It analyzes the tones present in the photograph and selectively works on areas of highlights and of shadows but leaves midtone areas alone. There are separate sets of sliders for adjusting the shadows, adjusting the highlights, and maintaining midtone contrast and color saturation.

This is a complicated control. I’ll describe what the sliders do in the next several paragraphs, but don’t be surprised if this description is a bit confusing. The way to understand what this tool does is to play with it and look at how the preview changes when you move the sliders around. My explanation will help you figure out why moving a slider has the effect it does, but messing around with this adjustment on your computer is the best way to understand it.

At the top of the Shadow section is an Amount slider. That controls the strength of the adjustment, with 0% being no effect on the shadows at all. In this case I applied a moderate 33% effect to bring out the background detail. The next slider, Tonal Width, controls the range of tones over which the effect is applied. Set it near 0%, and only the tones very close to the darkest ones will be affected. Set it near 100%, and almost all the tones in the photograph will be lightened.

The last slider, Radius, controls how wide an area the adjustment samples to determine what range of tones to correct. This is the part that is smart enough to figure out how to leave the midtones alone. The adjustment takes into account all the tones within a radius to find out which ones are the shadow tones that should be adjusted.

The Highlight sliders work the same way. The only difference is that the highlight tone width is measured starting from white and working down, instead of from black and working up. Most often you’ll apply only a very small amount of highlight correction. The 13% I used is a pretty potent effect.

The last set of controls ensure that the shadow and highlight adjustments don’t make the image look too dull. Color Correction controls the saturation in the areas being altered. It doesn’t have any effect if you’re working on a black-and- white photograph. Midtone Contrast does about what you’d think; it’s a way to control how snappy the print looks in the midrange. To some degree, it counteracts the effect of the Shadow and Highlight adjustments, so use it sparingly. If you get good at setting the Shadow and Highlights sliders, you’ll need to make only very slight midtone contrast corrections. The Midtone Contrast slider is very useful for fine-tuning the look of the photograph after you’ve set the shadow and highlight corrections.

Figure 4 shows a more typical use for the Shadow/Highlight adjustment to correct this snapshot from 1970. The settings I used are shown in Figure 5; I’ve circled the three settings that are different from Photoshop’s default settings. Since I was mostly interested in improving the highlight detail, I pulled

back the shadow amount to 17% and turned the highlight amount up to 15%. I boosted the contrast in the mid- tones by nine points so they have a little more clarity. That’s how little it took to produce the marked improvement you can see in this photograph. This level of improvement in family snapshots would make most photographers (or clients) very happy.

Three paths to better faces

Amateur snapshots can have pretty harsh contrast, so most amateur photos (or even professional ones made on sunny days) don’t flatter people’s faces. Most photo restoration requires increasing the contrast of the photograph, which can also do unpleasant things to faces. If the original photograph also was printed poorly, as many old photos were, restoring the blacks and whites to their full richness produces some very harsh skin tones.

Figure 6a was a commercial portrait that wasn’t badly faded; the print was badly made, so it was very low in contrast to begin with. The good news is that, because the print densities were undamaged, all it took to get a full- range photograph was a careful scan and a very slight amount of Curves adjustment in Photoshop. That yielded Figure 6b, which has a nice range of tones from black to white.

Technically it’s quite satisfactory, but it’s not particularly attractive. The original lighting in the photograph was too directional and came from too high an angle. When the child leaned forward, the shadows fell harshly on her face. Happily, there are many ways to improve this.

I applied the Shadow/Highlight tool (Figure 7) to the corrected photograph to get Figure 8a. Because I didn’t increase the midtone contrast in the adjustment, it softened those tones. In combination with slightly opening up the shadows and substantially reining in the highlights, this adjustment improved the face quite a bit.

Another way to fix the face is the good old Dodge tool. It only takes a few strokes to turn Figure 6b into Figure 8b. I set the radius of the tool to about the width of the child’s lips with the hardness at 30% (a fairly soft edge). I set the range for midtones and the exposure to 12%. Anywhere there was a dark shadow on the child’s face I dodged it with this brush. Specifically, I ran the brush under her eyebrows and across the bridge of her nose, over her eye sockets, and along the bags under her eyes. I also clicked the brush a couple of times in the whites of her eyes on either side of the pupils to bring them out a bit more.

Next I ran the brush over the “muzzle lines” running from her nose down to the corners of her mouth. I dodged just under her lower lip and along the dark- est shadows under her cheeks to soften them up. That’s everything; it’s not much! You don’t have to completely rework a face to soften its look; just tackle the darkest and most contrasty spots, and you’ll see a big improvement.

When the Dodge tool seems too crude and unresponsive, there’s a better way: use the History brush as a customized Dodge tool. I applied the curve shown in Figure 9 to the portrait and got Figure 8c. All those harsh shadows have been grayed out (along with everything else in the photograph). I assigned that state to the History brush and reverted to the pre-curves portrait. Now I could use the History brush to paint in that softening effect.

I set the brush to an opacity of 9% so that I could work the effect in controllably, with each stroke of the brush slightly lightening the shadows. I worked over the same areas with the History brush that I had with the Dodge tool to get Figure 8d.

The advantage of using the History brush is that it’s easy to customize the effect of the brush to alter tones exactly as you wish. For example, if the portrait had also had harsh, blown-out highlights, I could have pulled down the white point on the curve to a light gray and had a brush that would both lighten shadows and darken highlights automatically.

Using the History brush to dodge also lets you pre-visualize what the effect will be. Before reverting the history state to its pre-Curves condition, you can duplicate the modified image and keep it on your desktop as a reference. That way, when you’re working with the History brush, you can always see which direction it will be pushing the tones and how far it can push them.

For maximum control, I like to use a masked Dodging layer. Instead of applying the curves in Figure 9 directly to the portrait, use them in a Curves adjustment layer and paint the effect you want into the layer’s mask.

Hand-painted adjustment layer masks let you apply correction effects exactly where you want them. The effect can be as broad as half a photograph or as narrow as a single pixel; it’s just a matter of what radius brush you use to paint the mask.

You can apply any kind of Curves alteration you want this way. I do most of my dodging and burning-in with masked adjustment layers because I can produce effects a lot like dodging and burning-in does in darkroom printing. Unlike darkroom printing, I can have as many different dodge and burn-in effects going on as I want by creating a new adjustment layer for each particular flavor of alteration I want to make.

Good dodging and burning-in curves are intentionally super-strong so that you can paint them into the layer mask with a low-opacity brush, building up the changes you want stroke by stroke in a controllable way.

First I inverted the Curves adjustment layer mask to make it black, which zeroed out the effect of the layer. Now I could paint in the Curves adjustment just where I wanted by using a white brush to paint over the mask. Just as when using the Dodge tool and History brush, I used a small-radius brush set to very low opacity. You can see my results, along with the layer mask I ended up with, in Figure 10.

This method has all the advantages of using the History brush along with being completely reversible. If you make a mistake and dodge somewhere you didn’t mean to or overdo it, just change the brush from white to black and paint over your mistake. You can switch back and forth between white and black brushes any time you like, so that you can rework the mask as much as you need.

This is a great method for beginners, as well as advanced workers, because you never have to worry about doing anything irreversibly wrong. This requires no painterly skills. The better you are with wielding a (digital) brush, the more efficiently you’ll be able to do this, but you can erase or rework any mistakes you make, so you’ll always be able to get there bit by refined bit.

That’s it. You don’t need to be a Photoshop expert to give your photos a more professional look. A few tricks and a little practice with the digital brush is all it takes.


About the Author

Ctein
Ctein
Ctein is a technical writer and expert printmaker. He is also the author of Digital Restoration and Post Exposure—Advanced Techniques for the Photographic Printer.