Retouch Pro + Amy Dresser = Tutorial Heaven

I've never been big on video tutorials. I prefer to follow along at my own pace. So when I see postings for online events like "webinars" (a really ugly word, my son Max tells me) I tend to ignore them. But when RetouchPRO sent me an email about a "RetouchPRO LIVE" event with Amy Dresser, I signed up. The event interested me because:

1. Amy Dresser is basically the supreme goddess of beauty retouching and has become something of a patron saint to the RetouchPro community. Seriously, look at her work.
2. The event was scheduled to last 2 hours and the registration fee was only $10. Ten bucks to watch a top-notch pro retouch in real time? Deal.
3. She was going to retouch a photo of a man. You almost always see retouching done on photos of women, so I was curious to see if the gender of the subject would change the method of retouching.
   

The big event was yesterday. I loved it and I took notes. I'm not going to try to deliver all the information (and shouldn't anyway)—for that, you can go to the RetouchPro channel on the YouTube Rentals beta site where it will soon be added to their already large collection of rentals. The only downside is that it costs twice as much ($19.98). Read RetouchPro's explanation of the Youtube rentals for more info.

And now...some random notes:

On sharing information
If nothing else, Amy Dresser and I share the philosophy that sharing information is good. Some people are guarded about their techniques as if revealing their trade secrets will make them useless. Amy, on the other hand, knows that no one can replace her own artistic eye and vision. She doesn't need to hide anything because the real technique is in how the brain works. It's the decision making, the seeing that matters more than the Photoshop settings.

On skin
Amy doesn't think gender or age should change the way you retouch skin. "Skin is skin. I have the same approach to everything," she says. The look of the skin (gritty, smooth, dreamy, shiny) is determined by the style, not the subject.

On technical details
She doesn't pay attention to histograms. She never looks at the "info" palette. She doesn't mess with most of the settings in Photoshop or on her Wacom tablet. She describes herself as "not very technical." Nice to know that you don't have to know every little thing about Photoshop to be successful.

On workflow
She does some basic manipulation in RAW, starting with exposure and working her way down. After that, she has an action that sets up her organizational system of folders and layers. Her organization reminded me of a paper outline—it's just a structure that reminds you to attend to certain points, then you fill it in as you work.

On getting things done
Amy works from general to specific. In other words, fix the biggest problems first and work your way to the smaller ones. For example, she's not going to make one area perfect before moving on to the next. Move around the whole face, make everything better and then better and then...oops. Times up. The client wants the photo. Aren't you glad you have a pretty decent overall photo rather than half a face that's perfect and another half you haven't even touched yet?

On little steps
Amy made about 30 separate curves adjustment layers (and quickly) to fine tune the skin tone. When she does dodging and burning, she works at 3%. When she paints (to colorize something or to add a little white at the base of the eyelid, for example), I saw her use as low as 1% flow. This is typical of her tendency to build up many small steps rather than do one sudden change. That way, if you make little mistakes, then they stay little. It also helps cultivate a subtle eye.

On zooming in
More often than not, Amy keeps the photo zoomed out to how it will look in print. That way you don't waste time doing pore-level changes that don't matter. Look at what people are going to see, and if it looks good then why go down to the level of the pixel?

On photography
"I'm actually not a fan of photography." Biggest shock of the session to me. Remember, she is a retoucher, not a photographer. She says she never takes pictures. As for me, I'm a photographer who sees retouching as a means to an end. I retouch because I can't afford to send my work to someone like Amy Dresser, and I'm enough of a control freak to prefer doing things myself if I can't hire someone way better. So, I'll forgive you, Amy, for not loving photography. After looking at photos all day long, you need a break. My suggestion: music.

On using your weirdness to your best possible advantage
"If you have a weird talent and you can find a way to use it for your career, then, like, power to you." Amy always had an eye for detail and color. I would compare this to my mother-in-law, who (as I have mentioned once before) seems to have the equivalent of perfect pitch for color. Amy's visual abilities wouldn't help her much if she were filing papers all day, but luckily, she found a job that turns those abilities into gold.

For future events, look on RetouchPro. That Youtube rental thing (at twice the price) might not be quite the right price point, but if you try it, let me know.

Complete Portrait Retouch Workflow

Not long ago, NPR aired a story about a checklist for surgery success. Atul Gawande—a surgeon who also teaches at Harvard—offers compelling evidence that surgeons will get better results if they follow a simple checklist. The biggest challenge is convincing surgeons that they need it.

Of course, when we retouch a portrait we're not exactly saving lives. Egos, maybe, but not lives. Nevertheless, following a checklist (better known as "workflow") can streamline your retouching and help you get the best results possible. This post will tie together some of my tutorials to create a start-to-finish portrait retouch workflow. I will give a brief description of each step, but you will have to click on each step for the full tutorial. [I will come back and add photos to this post, but you don't really need them since each of the links has ample photos]

Step 1. Correct your white balance.
If you work in RAW, you will want to correct not only white balance, but as many other settings as possible. If not, you can open a curves adjustment layer and use the eye dropper from the curves dialog box to sample a white, a black, and a gray (or at least one of those). Correcting your white balance can have a dramatic effect on the overall color and brightness of a photo.

Step 2. Use curves to fine tune skin tone and color.
Even though you created a curves layer to fix white balance in step one, I find it more helpful to create a new curves layer devoted to improving the skin tone.

Step 3. Whiten teeth.
I usually warm up the skin in step 2, which has the side effect of warming up (i.e. yellowing) the teeth. If you were to whiten teeth before warming the skin, you would just have to repeat your work later.

Step 4. Clear up blemishes
Take care of the big problems with the skin first. I prefer the patch tool for most large blemishes, and the clone stamp tool occasionally. Remember to do each step on its own layer. Most people save a version of all the layers in case they need to come back and adjust something later. I have to confess, however, that I usually merge down when I am satisfied with a given step. If a client wants me to change the retouch (and, this sounds vain, but they never do), I can just go from where I left off.

Step 5. Reduce wrinkles (especially around the eyes) as needed.
This step also uses the patch tool, but I do it on a separate layer because my method (as you can see in the tutorial) uses adjustments in opacity. The main point in this step is to reduce larger wrinkles. Save the smaller ones for dodge and burn.

Step 6. Overall skin improvement using either a high-pass technique or dodge and burn.
Your choice of hi-pass softening or dodge and burn retouch will depend on how important visible pores are to you, how much time you have, and the look that you want. If you want a very soft look, a hi-pass softening or even the "foundation method" may fit the bill. It all depends on the style you want.

Step 7. Add sparkle to the eyes.
A little dodge and burn can create better catch lights and help give more interest to the eyes. If you used dodge and burn in Step 6, you can still work on the same D&B layer.

Step 8. Optional contouring with dodge and burn.
If you want to contour the nose, the lips, the cheeks, and so on, you can use dodge and burn to do so. This step is not always necessary.

Finally, don't forget to sharpen!
Maybe one day I'll do my own sharpening tutorial, but until then...
High-pass sharpening is one of the most popular quick techniques.
Adobe has some great recommendations for sharpening and they'll even point you to a long tutorial that covers several methods of sharpening. I use the sharpening programs created by NIK, which I love.

Photoshop Dodge and Burn Tutorial

"D&B"
In a traditional darkroom, dodging and burning refers to the manipulation of exposure to make selected areas of a print lighter (dodging) or darker (burning)—a technique covered in most photography classes. In Photoshop, however, the typical user doing a portrait retouch may never click on the dodge and burn tools—and for good reason. Rarely is "D&B" explained in Photoshop tutorial books other than in general terms, and usually applied to landscapes rather than people. Furthermore, finding usable information on D&B in forums is a foolhardy endeavor best left to people with too much time on their hands and a high tolerance for uncertainty. Or an insomniac with a blog.


The mystic order of hi-end beauty retouchers meets your high school art class

In Photoshop, the precision of dodging and burning can be taken all the way down to the level of a pixel (whether you should go to that extreme is up for debate). When it comes to retouching skin, the pro retouchers swear by (and at, I'm sure) D&B because it leaves the natural (a word which here means perfectly lit air-brush makeup enhanced) skin intact. While other "skin smoothing" methods rely on blur, which compromises texture at the risk of creating plastic-looking skin, D&B affects only shading.

At some point in your schooling someone (with wildly untamed curls, a smock, and Birkenstocks?) taught you how some careful shading can turn a 2-dimensional circle into a wondrous charcoal-smeared "3-D" orb. Erase the shading and the circle becomes flat. Now let's replace that circle with an ugly zit. The zit "pops" (sorry, as a Dad I am legally required to use this brand of groan-inducing humor) out on the face because of highlights and shadows. Tone down those highlights, lighten up those shadows, and the zit disappears. It's all about shading. Adjust the shading and crater-like pores lose their attention-getting shadows. Circles under the eyes? Gone. Wrinkles? Reduced. But wait! there's more. Want to create better bone structure? Sculpt perfect cheek bones? Add sparkle to eyes? Fill out lips and add extra shine? That's right, folks, all this and more can be yours for the low low price of...

Only 6 hours of your time! Per photo!

What? Doesn't sound like such a good deal? You'd rather just blur skin to smithereens in a few clicks and call it a day? I don't blame you. But before you give up on D&B, let me tell you about bread for just a minute.

I have a friend who makes the most amazing bread. Specialty flours. Supplies purchased in France. A custom built wood oven in his backyard. Poilâne himself would approve. Amazing stuff. But does this mean I'm going to build a bread oven in my backyard? No. I wouldn't even know where to begin. But this doesn't mean that I'm doomed to a life of store-bought bread. My wife makes a bread that can pass for artisanal that doesn't even require kneading.

The moral of this story is that it doesn't have to be all or nothing. The purists might disagree, but I say, learn some techniques, find a compromise that works for you, and go from there.

THE TUTORIAL

Step 1. Assess your photo

Here is the "before" photo:


I am using a stock photo because if it were an actual client of mine I couldn't say things like "Who does your eyebrows, Mrs. Potato Head?" Seriously, that is some criminal overuse of eyebrow pencil. But too bad, I'm dealing with skin here.

Before we start retouching, we need to assess the problem areas:

Her eyes look tired and red. The shading under her eyes adds to the worn-out look.

The skin near her mouth and chin area has some blemishes and dark spots.

Her lips are not bad, but a little better definition and fullness wouldn't hurt.

The overall lighting is making her face very flat.


Step 2. Create your dodge and burn layer

Some people like to do one layer for dodging and another for burning. I prefer to keep it all on one layer and switch between the tools.

Create a "New Layer" and in the dialog box change the mode (from the pull-down menu) to "soft light" and check the box that says "Fill with soft-light neutral color (50%) gray." I named my layer "Dodge and Burn," but you can name yours "Snooki" if it makes you happy. Now click OK, and we'll start dodging and burning on the gray layer we just created.



Step 3. The maligned Dodge and Burn tools—Use them.


Most people "dodge and burn" without actually using the dodge and burn tools. Instead, they use the brush tool with white or black paint. Prior to CS4, they had good reason to do so. The D&B tools were notorious for suddenly changing skin to shades of gray or orange. However, CS4 improved the D&B tools and added default settings that protect tones, so I think the actual D&B tools deserve your loyalty.

When the dodge or burn tool is selected, you will see some settings in the top menu bar that merit attention. You will be changing the diameter of the brush often, so learn to use the right (larger) and left (smaller) bracket keys on your keyboard to adjust as needed. The hardness of the brush should be extremely low (like 0%) for smooth transitions. The "Range" options let you choose to affect "Highlights," "Midtones," or "Shadows." You are more likely to get good results if you concentrate on the midtones. In fact, feel free to leave it there the whole time. The exposure setting should be kept very low, such as 5%. A low exposure setting means that the changes will be very gradual. Small repeated light strokes will give you better control of the effect.

Step 4. Choose an area and get to work.

I prefer to work by area and switch between the dodge and burn tools and then move on. For inside the eyes, see my previous eye tutorial. The following picture shows one of the eyes as seen when only the gray D&B layer is visible (you click the eye icon in the layers palette to toggle visibility on and off for any layer):

The lighter the gray, the more I dodged in that area (and the darker=burned). I brought out the catch lights in the eyes and I dodged the dark circles and wrinkles under the eye a little at a time (and changing the brush size to suit the area) until I got passable results.

Notice that I said "passable." A pro retoucher (and that is not me—I'm a photographer) would spend more time and do much more detailed work. But then, a photo used for a cosmetics campaign will be scrutinized more heavily than most portraits. What I am proposing is something that you can do in about 20 minutes (or less) once you get used to it.

Compare this...

to this...
It still looks natural and has exactly the same texture as before, but her eyes now look better rested. I could have done more, but I think it's better to do stay subtle.

A few tips before moving on to another area:

• If you have access to a pen tablet, your D&B "sketching" will be much easier. If not, well, be glad I'm not telling you to do pixel-level editing
• Zoom your view in and out to keep things in perspective. Don't bother doing individual pixels. Zoom in to about 300% when you need to get close for more control (changing your brush size as needed), then go back to 100% as much as possible. Finally, make sure you zoom out to see the whole image once in a while.
• If your skin tones start to shift (toward gray or orange), try switching to the "sponge tool" (it's in the same pull-down menu as the D&B tools) and under "mode" in the top menu settings select "desaturate" (to tone down the orange) or "saturate" (to move the gray back toward normal skin color. I use a higher flow (20%) with the sponge. But remember that if you are having a lot of problems with tone shifts, you are probably overdoing it and/or not being precise enough with your brush.
  

Step 5. Skin imperfections

Theoretically, you could retouch every blemish with D&B, but I wouldn't recommend it. Remember that I'm trying to steer clear of six-hour retouch sessions. For large blemishes, I would use the patch tool or the clone stamp to save time. If your subject has a very bad complexion (i.e. bad acne over most of the face), you may have to resort to the foundation method or some form of hi-pass skin softening. You can still use D&B for contouring (see step 6).

In the photo here, there is just a patch of blemished and uneven skin to the left of the mouth.
As in step 4, I will dodge out the darker areas to make it even with the surrounding skin. When I accidentally lighten something that doesn't need to be lightened, I simply switch to the burn tool and darken it up again. With only the D&B layer visible, you can see the dodged section on the lower left side:

In very little time, you can make the area vastly improved (or perfect if you're willing to take a long time):


Step 6: Contouring
This is the fun part. You can improve the shape of the face, lighting, and the lips with a little D&B. First the lips:

Dodge the highlights to get a more plump shape. You will want to accentuate the highlights and extend their reach. Next, burn to create more shadow near the bottom and more definition (like a light lip liner) around the edges (if needed). The shadows at the base of the lower lip will give it that pouty look.

Pay attention to how in the "before" photo, the lower lip has almost no highlights in the middle area:

After dodging to even out the highlights and burning a little at the base, the lips start to look more full.
Now you can contour as much of the face as you like. Here is what I did:

I dodged a highlight down the nose and burned some light shadows along the sides of the nose. This gives better lines and can be a great way to make the nose thinner as well. If you know how to do makeup or if you have illustration experience, chances are you can do a much better job than I have here. If you have absolutely no experience, just pick up a magazine and look at the highlights and shadows. The dark dot at the end of the nose shows where I burned in to reduce glare.

I also brought out the cheekbones with some D&B because the lighting had flattened them. I burned a little more definition into the chin, and I dodged a little more sparkle near the eyebrows. You don't need to change any of the settings (from your 5% and "midtones" as seen in step 3) except the brush size, and course switching between dodge and burn as needed.

This doesn't need to take much time because we are going for overall improvement rather than a 6-hour fashion spread perfection. As a final step, you can create a new blank layer (just normal blending mode, not a gray soft light layer), sample a nice pinkish tone, and dust areas that are still on the blotchy side with a soft brush (not the D&B tools) set to a low opacity (5-8%).

Here is the before:

and the after:


Here they are side by side:























As one final note, I should point out that I am a big advocate of subtle retouching. I don't think you should look at an image and say "Wow! Look at that retouching!" You can, of course, use the principles in this tutorial to do as much or as little as you like.

Vibrant, Sparkling, and Sharp Eyes

Introduction
If we look at poetic excess as an indicator of importance, the eyes may very well be the most important part of the body. Here are a few overwrought gems of proof:

There are whole veins of diamonds in thine eyes,
Might furnish crowns for all the Queens of earth. (Philip James Bailey)

Thine eyes are springs in whose serene
And silent waters heaven is seen.
Their lashes are the herbs that look
On their young figures in the brook. (William Cullen Bryant)

Eyes, that displaces
The neighbor diamond, and out-faces
That sun-shine by their own sweet graces. (Richard Crashaw)

You get the idea.

Can the eyes in a photo possibly live up to such elevated language? It's a tall order. For one thing, photo paper tends to steal some of the life from eyes. This tutorial is meant to help you bring that sparkle back while remaining true to life. I don't promise eyes of diamonds and silent waters of heaven, but I do guarantee that these easy steps will make your portraits better represent what you see when you look into someone's eyes.

Here is a the same (bridal) portrait I used in a very stylized dot project.
The eyes don't quite do justice to what I saw in real life when I took the picture. So my goal is to restore some of that brightness and clarity. I don't want to change the color of her eyes. I just want to bring out what the camera didn't quite capture. I am going to do this in two parts. First, dodging and burning, then, sharpening.

PART I: Dodge (and Burn)
1. Duplicate the layer (Mac: Command–J. PC: Ctrl–J). It's just a good habit.

2. Create a new layer. In the New Layer dialog box, pull down the "mode" menu and select "overlay" and check the box that says "Fill with Overlay-neutral color (50% gray)."
In the layers palette, the new layer will look gray like this:
It's gray because it doesn't actually contain the image, it will simply overlay the effect.

3. Now it's time to dodge—or lighten—the eyes. Select the dodge tool from the toolbar on your left. Next, look at the dodge tool menu bar at the top. Here, you can select brush type (you will want a basic round brush), hardness (somewhere in the middle will work well), size (depends on your photo), as well as the "range" (shadows, midtones, highlights) and exposure (the intensity of the effect, which you should keep very low, such as 7%).
Let's start with the highlights. Zoom in on the eyes and look for the catchlights (the whitest reflections that go across the pupils).
The photo I am using was done in natural light. If I had used studio lighting, you might see circles (from an umbrella reflector) or a more rectangular shape (from a softbox) or the tell-tale doughnut shape of a ring flash. But these natural catchlights are less uniform and not as intense as studio lighting. To make the lights stand out a little more, just use the dodge tool set to "highlights" (with a small brush size to match the catchlights) and paint over the light parts until they stand out a little more.
You can click the layer visibility on and off to see the change as you go. Don't overdo it. If you so desired, you could paint little half-moon shapes as faux catchlights, but that can quickly lead to a fake-looking retouch.

4. Now let's improve the whites of the eyes. Start with the "midtones" selected from the dodge tool menu (but feel free to alternate between highlights, midtones, and shadows as needed), and brush along the whites of the eyes to lighten them up. But beware! Too much dodging and you're headed for Village of the Damned territory.
Keep it subtle and let it get darker toward the edges.

5. The last step of our dodging is to lighten the iris. With a brush size that fits between the iris and the pupil, paint around each iris to lighten it. Steer clear of the edges, which look better against the whites if they stay dark. You will have to experiment with highlights, midtones, and shadows. Your goal is to lighten while keeping a natural look.

That's the end of our dodging step. If you want to burn (make darker) anything (for example, the pupil), you can do so by switching to the burn tool. But for the most part, you will want to brighten the eyes. When you are happy with your work, you can merge down or flatten the layers. So here is the BEFORE so far:

and here is the AFTER:


PART II: Sharpen
1. To really make the eyes come to life, you can sharpen them. Sometimes, if the eyes are already bright enough, you can skip the dodging and go straight to this step. Duplicate your layer.

2. From the top menu, select Filter-->Sharpen-->Unsharp Mask. It's counterintuitive (a relic term from a darkroom process), but the unsharp mask will make your image sharper (by increasing contrast).

A dialog box will let you adjust the amount (intensity) of sharpening, the radius (how many pixels are grouped together as units to be sharpened), and the threshold (how much a pixel needs to differ from its neighbors in order to get sharpened). The settings depend on your photo, but there is a lot of room for variation. Do whatever you think looks best. Try starting with an "Amount" between 80 and 180 percent, a "Radius" between 1 and 5 pixels, and a "Threshold" between 1 and 4 levels. If the preview box is checked, you will see the effects (you can click on the eye in your image to make it appear in the box, and you can zoom using the + and - boxes just below the preview window). In the preview window, you can also click and hold to see the "before" and release to see the "after." Note the difference between these settings...
and these ones...
When making your sharpening choices, focus on the iris and ignore the rest of the picture. The increased radius is making the effect stronger, and the area around the eye is looking oversharpened. But if you only look at the iris (and pupil), it looks good, so I'm sticking with those settings.
Click OK when you like what you see.

3. You will now add a black layer mask to your sharpened layer. Click on the layer mask icon at the bottom of the layers palette while holding option/alt to add a black layer mask on your sharpened layer.
4. Your sharpened effect is now hidden and you can paint it back in selectively by making the black mask active (click once on it) and then using the brush tool (b) set to white (If black is in the foreground, just click "x" to switch it to white. If your colors are set to something other than black and white, click "d" first) to paint over the middle of each eye:
I would avoid the whites, because veins will become more prominent. But you might want to sharpen the inner corners (what are those called, anyway?). Since you have done all of this on a separate layer, you can dial down the opacity if it looks too sharp.

That's it. In very little time (once you get the hang of it) you will have vibrant, sparkling, and sharp eyes (Well, not your eyes, sorry. You've been staring at a computer monitor for too long and your eyes are looking red and tired.)
Here are the eyes BEFORE:


and AFTER:


Here is the finished retouch (I recommend that you click to enlarge):
The "after" actually looks more like her real eyes than the "before." The change is subtle and realistic.

Using curves in Photoshop to adjust tone and color in a portrait

This tutorial is the first in a series that will teach you a basic workflow for portrait retouching in Photoshop (some of the future tutorials will also work in Elements, but not this one). I will try to give you enough information to get good results without getting mired in pro-level details. Future posts will include blemish removal, teeth whitening, eye retouching, and so on, but before you do any of those things you need to fix the overall lightness and color.

1. Open a photo (Your next family Christmas card? A new Facebook profile picture?). Most photos will greatly benefit from the following simple adjustments. And unlike one-click automatic adjustments, the following method gives you customized control. Once you understand the basics, you can correct color with more precision or even stylize color in unexpected ways.

I will be using this engagement photo:

To be fair: Step 2 (in which you duplicate the background layer) is not strictly necessary in this tutorial, but I think that step should be automatic (for reasons that will be apparent in future tutorials), so you may as well practice good habits now.

2. Hit Command-J (PC: Ctrl-J) to duplicate the background layer. You will now see "layer 1" in your layers palette just above the background layer.
Note: If the duplicate layer does not appear, double click on the word "background." This will bring up a dialog box to rename the layer and "unlock" it. Hit return to name it "layer 0" or you can rename it "original" or anything else. Some people do this as habit before duplicating a layer.

3. Open what is called a "curves adjustment layer" by clicking on the pull-down menu in the bottom of the layers palette:
Once you have done that, you will see a new layer (which should be active) that looks like this:

Notice that there is no thumbnail of your photo on your curves layer. That is because it does not actually contain your photo; it only contains the adjustments themselves. On the left side, that curvy line represents—surprise—the curves adjustment, and on the right, a layer mask (which will not be used in this tutorial (but for the curious: it allows you to selectively remove or "mask" adjustments).

4. Next, you will lighten or darken your photo on the curves adjustment layer to get better skin values. Double click the curve box on the left side of that layer to get a dialog box like this:
It looks intimidating, but we are going to keep it easy.
A quick explanation to demystify it: the horizontal axis represents the tonal information within the image, running from black (left) to white (right). The vertical axis shows how much information falls within various tones. For example, the two "mountains" show that my photo has a lot of light and dark tones, and the "valley" shows that it has fewer midtones. Naturally, your photo's histogram will differ. If too much information is on the far left, you probably have an underexposed image. And if too much information is on the far right, you probably have an overexposed image.

Pep talk digression:
I am not going to pretend that curves adjustment layers aren't powerful and complex tools. They are. But then, so are computers, right? And my three-year-old daughter enjoys playing Nick Jr. games without knowing how to program. So my point is, Dora now, programming later. Or not. You may never need to get very complicated.

And now, it's curves playtime. See that line cutting diagonally across your histogram? You can click anywhere on that line (top right is white, bottom left is black) and an adjustment point will appear. You can add as many points as you want, but let's just stick to one for now. Help! you say, I was too hasty and I've already made ten of those points on the line! No problem. You can click on a point and drag it off of the line (drag way off, out of the box) to make it disappear.

Since your photo will vary, this is a good time to experiment. You probably will want to stay away from the extreme ends. Also, don't go hog wild. Keep it subtle. Set a point and pull it toward the right and down to darken, or to the left and up to lighten. As long as your "preview" button is checked you can see the effect in your photo. Toggle the checked preview box on and off to compare. I decided to lighten my photo a little bit. Here is what my curves adjustment looks like:
A small, but not insignificant change. Depending on your photo, you may want a larger adjustment. When you have something you like, click OK.

5. Now it's time for another curves adjustment. Add another curves adjustment layer (so you can appreciate the changes for each step) just like you did in step 3. This new curves layer will appear on top. Double click as you did before to open your new adjustment layer.
In the dialog box at the top left it says "Channel RBG" along with a pull-down menu from which you can choose the red, green, or blue channel. Go ahead. Check them out. You can set a point and pull one way or the other on each of these channels as we did in step 4. Pull to the left and increase one color, pull to the right and bring out its opposite.
Red (left) is opposite Cyan (right).
Green (left) is opposite Blue (right).
Blue (left) is opposite Yellow (right).
Start with the Blue channel:
Since I want a nice warm photo, I will click in the dead center of the line and pull toward the bottom right (the yellow side).

With my preview box unchecked you can see the before:
And with it checked on again, the after:
The second one looks warmer, and in my opinion, more inviting. Now do your own blue channel adjustment, but don't click OK. You will want to move on to the Green channel before you're done.

6. Now that I've warmed up the blue channel, I am seeing a bit too much green. So in the Green channel, I am going to set a point in the middle (as I did before) and drag it a little to the blue side.
How do you know how much and which colors to change? Experiment and you will educate your eye. Some people seem to be able to look at a photo and say "too much blue" or "too much red" with no problem. If you are not one of those people, experiment with the channels and see what pleases your eye.

Another pep talk digression:
There is no right answer when it comes to color. For example, a lot of people are doing heavily yellowish looking photos right now. For those not into that trend the yellow may represent an ugly color cast. Similarly, as a rule, bluish skin is undesirable. But for a certain steely and desaturated look, it may be perfect. You decide what looks good. The important thing is that you are no longer at the mercy of an auto-adjust button.

7. I am leaving the red channel alone, but if you want to tweak it, you know how.

8. One final curves adjustment will give added contrast. Add another curves adjustment layer. Double click and leave the dialog box on all channels (as opposed to the individual R, B, or G ones). This time you are going to add what is called a classic "S" curve by manipulating two points. As you place and then pull a point somewhere in the top half (not too high up or you will clip highlights) to the left side, and another point in the bottom half (not too far down or you will lose shadow detail) to the right side, an S-shaped curve will appear, and more importantly, you will increase contrast. Here is what my subtle s-curve looks like (not much of an "s," is it?):
The more prominent your "s," the greater the contrast in the result. Try it on your photo.
That's it for now. If you practice this tutorial on several photos, it will soon become second nature.

Below are the before and after photos.

before (not bad, but not as warm as it should be)
after (warmer, with a little more contrast)

The differences you see may depend upon your computer monitor, but what I am seeing is an improvement that is not overstated. The more portrait retouching I do, the more I am a fan of restraint. Unless you are going for a highly stylized look (which I also love), you don't want something that screams out "Hey! I've been Photoshopped!"