Monday, December 14, 2009

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.

3 comments:

michelle said...

Huh. While I don't love extreme zit close-ups, this is probably a post I will refer to multiple times in the future as I can never remember how to do this!

The Three Amigos said...

I've only used the healing brush tool. I'm so EXCITED to try out the patch tool. I don't think I even knew it was there. Thanks!! I can't wait!

slefler said...

Marc, this is amazing. I use this for my landscape photography when I end up with a spot on my sensor (due to constant lens changes). This has saved many images that would normally need to be tossed. And it is so quick. And your directions make it so simple. Good-bye to the clone stamp tool! Thanks for your posts, I really find them useful.