Hi-pass skin softening: 4 great tutorials

I've been too busy with a photo shoot today to write my own tutorial, so I'm going to give you an introduction to another skin retouching technique and then point you in the direction of four great tutorials. The technique is usually called "hi-pass skin softening" because it uses the hi-pass filter as a way to soften skin without losing too much detail. Each of the tutorials below is a variation on the hi-pass theme.

As I mentioned in my last post, the problem with the "foundation" method is that it is like adding makeup. It can quickly lead to a dull plastic look that no one wants. So why use it at all? Well, the fact is, if you use it in moderation, it can be a nice way to soften skin in a photo that has an overall soft feel—such as in the bridal photos below:


For most situations, however, a method that uses the hi-pass filter should be your top choice. Keep in mind that there are nearly as many Photoshop recipes for skin softening as there are recipes for chocolate chip cookies. Cookies are on my mind because Michelle made some last night and was not thrilled that they were on the flat and crunchy end of the cookie spectrum. That didn't stop any of us from eating them, because at the end of the day, it's hard to go horribly wrong with butter, sugar, flour, and chocolate.

So what are the staples of a hi-pass recipe?

• at least one new layer
• a change in the layer blending mode
• the hi-pass filter
• a blur
• a layer mask to paint in or out the effect

The following tutorials are all good and you should try them all out if you want to find your favorite.

Tutorial 1: hi-pass at the venerable lynda.com site
I have to confess that I am not a fan of video tutorials. I prefer to follow steps at my own pace rather than pause, rewind, pause, etc. But this video is worth a look. It covers more than just the hi-pass method (you'll see our friend, the patch tool, for example), but the heart of the video is this:

1. new layer, filter---other--hi-pass with a radius set very low
2. pull the saturation down to 0%
3. change the blend mode to overlay or soft light
4. use command-i (PC: ctrl-i) to invert the layer (sharpness now becomes blur)
5. add a layer mask and paint out the effects (or add a black layer mask and paint them in)

Like many tutorials, this one uses a hi-end fashion shot rather than your average portrait. To me, that is the equivalent of using a pro photo against a white background to teach someone about to extracting objects from the background (which you also see a lot). It's not real-world Photoshop for the average user.

tutorial 1 is the only one that sticks to the hi-pass filter alone. The other three all use a double layer (low-pass/ hi-pass) approach.

Tutorial 2: "airbrushing" at the Photoshop tutorials site
In this tutorial, you duplicate your background layer twice. One layer will be a layer of blur (people used to use the Gaussian blur, but now Surface blur is the new favorite because it helps keep edge details) and the other layer will be a hi-pass layer. In tutorial 1, the hi-pass layer was inverted to become a gentle blur, but here it will remain in its original sharpened state, where it will work together with the layer of blur to form a compromise of smooth skin and detail.

Tutorial 3: freeonline classes "professional skin smoothing"
Same principles as tutorial 2, but with some variation in blending mode and use of the "smart object" feature.

Tutorial 4: byRo's quick "de-grunge" technique at RetouchPro
This is a favorite among forum members at RetouchPRO—a forum devoted to retouching. My own experience with the forum is mixed in that it's kind of a beast to navigate, but it has many hidden treasures. It reminds me of the chowhound message boards where you can find stellar recommendations from people who know food like nobody's business, but where you also have people who drop in just to ask the same question that has been asked 500 times before.

But back to the de-grunge. Aside from the name, which I find off-putting for some reason, this is a great tutorial. I have used this exact method many many times. The tutorial is clear and relatively simple. The results will be good—and this goes for all hi-pass methods—if you plug in the right numbers (which is the hardest part since there is no one-size-fits-all answer).

Hi-pass methods are worth exploring, but don't even think that we have exhausted the skin retouch possibilities. There's more to come.

A word about skin texture

Reducing wrinkles or removing zits is relatively easy compared to the challenge of improving the overall complexion. A couple of posts ago, I showed you a blur-based technique for skin softening. I compared it to foundation because the powdery blur improves skin at the risk of making a person look fake. Women who use a good deal of makeup already don't seem to mind the airbrushed look at all, but I would never use the technique on men. Sounds sexist, I know, but the problem is that since the "foundation" method is based on blur, any man old enough to shave is going end up with a Halloween-hobo style smudge of skin and stubble. And for those men with baby-smooth skin who probably don't need to shave more than once a month (the ones we always see in shaving commercials) anyway, skin softening is only going to make them look like the Adam Lambert album cover, which is fine if that is what you're going for, but not every guy wants an androgynous mannequin-like complexion.

I am also not a big fan of the "foundation" method used on anyone who doesn't normally wear makeup (that means kids—let's hope—and a good number of women as well). So what do you do in those cases? Well, you have to find a technique that does a better job of preserving texture. I'll cover that very soon.

For now, I just want you to look in the mirror. Look at your skin and notice how much the texture changes from one area of your face to another. The nose is not the same as the forehead, neither are the cheeks the same as the chin. Some lucky people have nearly invisible pores, while others, like myself, have craters that are visible on google maps.

One thing I can tell you is that the perfect skin retouching software or plug-in or action has yet to be invented.

As a final example, look at Jame's Cameron's "Avatar" (crossing my fingers that it will be amazing). The close-up of the animated skin shows his attention to detail—namely, flaws and variations. (Ironically, this is the kind of thing we try to eliminate in actual human stars). I read an interview in which he claims that the technology he used for the animation is so good that he could have just as easily made perfect duplicates of humans. As my wife likes to say, "I'll be the judge..."

Photoshop wrinkle reduction with the patch tool

When you retouch skin on anyone older than 30, there's a good chance they would appreciate a little wrinkle reduction. Don't get out of control. After all, wrinkles show character, and you still want the portrait to look like the person.

Once again, I'll use a stock photo to avoid embarrassing a client. Here is a mature woman with some fairly prominent wrinkles:

I don't want to do some grotesque transformation that makes her look like a 20-something model. I will use the patch tool to reduce the signs of aging in a subtle way.

What I will show you can be used on any area, but I will focus on the eyes (well, on one eye).

1. duplicate the layer and work on the top layer. We will be lowering the opacity later to let some of the original wrinkles show through from the original layer below.

Before we proceed, a word about wrinkles...
I think it was in one of Katrin Eismann's great books (the best out there for some pretty hard core advanced techniques) that I first heard a retoucher bother to explain how wrinkles work: they work their way out. Those crow's feet that stretch down the cheeks are not uniformly deep. The newer part of the wrinkle will be further away and lighter than the wrinkles that have been there for years. This is good to know because you might want to reduce the newest part of the wrinkle more aggressively than the rest.

2. With the patch tool, lasso a good chunk of the wrinkles closest to the eye. Since you are going to have to drag to a good patch of skin to heal the area, the size of your selection will vary. I usually drag to the cheek or the forehead—whichever has a good sized patch of skin with small pores and no wrinkles.

Once you drag your selection to a good patch of skin, you will get a very unrealistic "healed" spot like this:


For now, you want to eliminate most of the wrinkles (even the newer ones). Keep working, section by section, until you get something like this:

I didn't eliminate every single wrinkle, nor did I try to get a perfect texture. It won't matter when we get to the next step.

3. Now you will reduce the opacity for the sake of realism. I reduced it to 48%:

You can still see wrinkles, but it's a big reduction when compared to this:


4. At this point, you can flatten the image. Next, you can duplicate the now-improved background image and repeat the wrinkle reduction process on the newest wrinkles only. In the photo below, you can see how the lines that extended down the cheek are gone:


5. Reduce the opacity of your top layer (this time I did 30%), merge down or flatten, and the eyes are done.


One more note about wrinkles that I learned from Eismann...
Vertical wrinkles (worry lines) are the worst. Feel free to attack them more aggressively.
You can quickly go from this:

to this:
As before, dial in an opacity reduction if needed (but keep the percentage high this time).

And now, a final look look that shows the retouched side and the unretouched side:

Of course, normally, I would have done both sides at the same time, but this helps you see the difference the patch tool can make.

Skin Retouch Step 1: The Patch Tool, your new best friend

On the first day of retouch posts yours truly gives you...

the Patch Tool! My favorite weapon in the skin retouch arsenal. This post will give you my completely biased view about why Photoshop's patch tool should be your new best friend for retouching skin.

But first, some clarification on a few points:

1. A pro retoucher would most likely be horrified by every post I do this month. Why? Well, it's like when I was in grad school and the philosophy professors were horrified that the French lit professors included not just Descartes, but even Plato and Aristotle in their syllabi. First, objected the philosophy profs, those lit professors should stick to literature and second, how can you possibly cover Aristotle in a week? This comparison comes to mind because I was doing grad work in literature while my wife was working in the graduate program of the philosophy department. I heard those complaints all the time, so I decided to take a grad class in philosophy and see what all the fuss was about. For an entire semester, we plodded through Descartes' Meditations. The smartest student in the class liked to stroke his imaginary beard and gaze out the window while exposing the logical flaws of the cogito. By week three, we were still on the first meditation and I knew that this would be the last philosophy course of my life. My point? The real pro retouchers will dodge and burn, burn and dodge until their eyes are ready to bleed. It's really impressive, but it's not my world.
   
2. Random digressions are par for course with me. Sorry. Let's get back to business.
   
3. This post is just the first step, the elimination of blemishes. I mean, even if you want a very natural and unretouched look, I doubt you want to memorialize a zit.
4. Out of consideration for my clients, I'm using a stock photo of a girl with typical teenage skin problems. So here she is:
   

She looks pleasant. Nice smile, but I bet she'd like some help with the skin. Most people would run to the clone stamp tool, but my guess is that most of them haven't given the patch tool a fair shot. I use the clone stamp tool all the time for getting rid of distracting backgrounds, but even in my tutorial on that topic, I make use of the patch tool.

Common problems people have with cloning skin include obvious edges and differences in lighting between source and destination. With the patch tool, it's easy to avoid both of those problems because 1. you lasso your own shapes (rather than stamp a circle, for example) and 2. some algorithmic magic beyond my comprehension helps you clone out a blemish without destroying your lighting.

Let's look at a section of the girl's face:
As a first step in skin retouching, I just want to get rid of the large blemishes. My own philosophy is that temporary things, like zits, get retouched and more permanent "flaws" (like scars, which I think we should embrace) only get retouched if the person asks for it.

Using the patch tool on skin is very easy. Select it (j), draw a line around the area you want to fix—and make it sloppy. Sloppy is fine. Sloppy is good because an irregular line tends to blend well. Here's a super quick selection of a zit (lovely, isn't it?):

Once it's selected (and sorry, but you'll have to imagine this step—no screen grab), click inside your selection and drag to a place that doesn't have the blemish but that has a good texture for the area you want to repair. As you drag, you will see a sort of cloned view inside the your selection, but remember, your end result will not be a direct clone. Look for texture that lines up well. Don't worry about how dark or light it looks. When you let go, your patch selection does its magic:
I didn't mention settings because the default setting of the patch menu should already be "source," which is what you want.

From here on out, it's just a matter of rounding up all those blemishes. Sometimes I lasso a few at a time, sometimes I take an area in smaller parts. It's just trial and error. Make an error and you can just go back a couple steps in the history panel and try again. You can clean up a whole face in a relatively short time.

Here's the "before" section:
and after only a minute of quick and sloppy patchwork:

I haven't eliminated every little problem, just the most obvious. But what you see here is the result of no more than a minute of lasso a problem area/click/drag to good area/release/ repeat.

Try it, you'll never feel like using the clone stamp for skin cleanup again.

Finally, a word of warning: Since the patch tool blends with the surrounding pixels as it heals, you need to avoid getting too close to sudden changes. For example, if I were to make a selection of skin too near her lip, I might end up with a kind of muddy rose blur. Three possible solutions to that sort of problem:
1. pay closer attention to the relationship between the selection and the area you drag to. For example, the zit near the corner of the top lip can be selected and dragged to the side in a way that lines up the same lip/skin transition and your results will look good (just pay attention to how things line up as you drag).
2. if need be, you can use a selection tool (such as the lasso tool) to define an area large enough to include both the problem skin near the lip and the good skin while excluding the lip itself, then use the patch tool within your selection. The blended result won't use any pixels that aren't in your selection, hence, no muddy blur. This is something I might find myself doing around a brunette's hairline to avoid smudgy looking blends.
3. the formerly maligned clone stamp can come to the rescue.

December Monthly Special: Skin Retouch

Back from Paris with a souvenir from the plane ride home: a stomach flu that has made the rounds through our whole family. Nothing conveys the spirit of giving like a virus. Getting sick is kind of a holiday tradition for us. Other people open advent calendars to find sweet surprises, we start each day with a new symptom. On the first day of Christmas, my daughter gave to me, a fever of one hundred and three. On the...wait, where was I? Oh yes! The December Monthly Special!

I know that the month is half over, so I'm going to get very specific and work on an end-of-the-year goal: tackling the dreaded question of skin retouching. How to retouch skin is the number one question posted in forums devoted to photo retouching. OK. I just made that up, but still...it sounds true, doesn't it? I mean, what else would it be? How to add a fake tattoo? (Clients ask for this all the time, don't they? I don't know, Marc. That portrait of my baby is beautiful, but it seems like something is missing. Perhaps some angel wings, a full sleeve, and her name in Kanji just above the diaper? What do you think? No? Too much? A butterfly on the ankle then?)

When I first began my "starters" section, my intent was to build up steps that could then become a recipe. The first recipe was meant to be the portrait retouch workflow. Most of the elements are already there—color correction, whitening teeth, brightening eyes, and so on—but skin retouching is the dreaded beast that I have saved for last. I had a mega-post in mind: the ultimate skin retouch tutorial that goes over many possible methods and evaluates each one, but a more realistic goal might be to break it down into multiple posts.

Wait! Did I say "realistic" and "goal"? And in the same sentence? That won't do. I prefer challenges. I haven't done more than 10 posts in a month since May, and I just noticed that it's December 13, which just happens to be twelve days until Christmas, so I am going to do Take-Out Photo's version of an advent calendar: 12 posts in 12 days. Not every post will be about skin retouching, but many will. I won't bother with the shared linkies this month, but they will be back in January.

Who knows what surprises you will find? One thing I do promise: no viruses.