Let’s jump right in and start discovering all the fun that can be had with these rules for creating the illusion of depth!

The 7 secrets are...

1. Use “clean edges” only in this one specific place (and be sure to leave them out of these “wrong” places)

What on earth is a “clean edge” you ask? Great question.

It’s simply where you have a darker value next to a lighter value and there is a clear, defined edge where you can see that it changes from dark to light. There is no part where the value fades gradually from light to dark; it just goes straight from the light side to the dark side.

(There is also no outline between these two values. You’ll learn the reason why in secret #2.)

A “clean edge” will almost always indicate where one object is in front of another object in a drawing. You probably already know what this looks like instinctively.

Think of a chin that is in front of the neck. There is a hard “clean edge” around the chin where it curves around and disappears from our line of sight. This makes the chin appear to be in front of the neck—even though we’re drawing on a flat sheet of paper.

Here's a great example of what a clean edge looks like...

See how it creates the illusion that the dark edge goes behind the lighter edge? Pretty cool, huh?

This all sounds super simple—and maybe even a little bit obvious—right? Yet many artists completely miss this important detail and so the elements in their drawings begin to blur together.

And even worse, sometimes well-meaning artists put hard edges into the wrong places in their drawings without understanding what it means.

So where’s the wrong place to put a clean edge? That would be anywhere that you should be able to see the full surface of something.

Let’s take a cheek with wrinkles for example. Most wrinkles are places where the skin curves gradually into a “dip” and comes back out—but we can still see all of the skin, even though it “dips” into the wrinkle. It never curves so far in that part of the skin goes “behind” and out of our view.

So in cases like this, we must avoid hard edges or we will create a place that confuses the viewer and makes them feel like a wrinkle is actually the edge of something, or maybe even a scratch or other blemish on the cheek. Certainly not the wrinkle they were trying to represent.

There are countless other situations you’ll run into “clean edges”. Start looking—you’ll notice them everywhere now. You can learn more about clean edges and how to use them to your advantage here.

This next secret will show you what not to put around the places where clean edges should go...

2. Why “coloring book” outlines are the fast-track to a flat drawing

Drawing a thick, dominant line to represent the edge of something is the equivalent of a big red “STOP!” sign in your drawing. Outlining your drawing will kill your hard-fought depth and dimension faster than you can say “coloring book,” and it has everything to do with light.

Take a look at your face in the mirror, do you see any thick black lines around your head?

What about around your eyes?

I’ll bet your answer is no—unless someone just outlined your face with a magic marker—and here’s how I know…

Your head is cylindrical! From the tip of your nose to the back of your head there is a gradual transition—as though you were working your way around a globe or a basketball. And when you follow the shape of an object to the edge, you simply see whatever thing is behind that object.

It might be the wall behind your head, or the computer screen you see behind your hand when you hold it up. Either way, there isn’t a big outline drawn around your hand, your head, or any other object in the “real” world. We simply see the edge of one object next to the background that is behind it.

So, what happens when you put a thick line instead of a “clean edge”?

Well, you’re telling anyone viewing your drawing that they are looking at an object that has no more depth than what they see on the paper. There’s no illusion to it—what they see is what they get.

This next point will teach you how to create the “shape” of an object without drawing big outlines around it...

3. Here’s why values that show depth are always in a gradient — even if it’s a flat object

First, let’s get that big word out of the way: gradient. You may know what a gradient is, but if not… it simply means that the value (remember that means how dark or light a color is) is constantly and smoothly changing from a lighter value to a dark one (or vice a versa, if you prefer.)

Here’s an example of a gradient…

Notice how you can’t point to a specific spot and say, “That’s where it starts getting darker”? Because it’s constantly getting just a little bit darker (or lighter, if you prefer.) So there’s no place where it just stops or starts.

Okay, so now that you know what a gradient is…

...how do you use that to make your drawings awesome?

Pretty simple, actually. Make sure that you always use a gradient as you are shading your drawings. Unless there’s a really specific use — like a dark background that needs to disappear into infinity — you never want to break this rule.

(Psst… also, don’t miss the secrets for amazing shading you can find at the end of this article.)

So why is it that everything is a gradient?

Well, most things that we draw are going to have some “curve” to them. They’re not flat objects. So as an object curves — it could be a cheek, a nose, an eyeball — it moves to an angle where the light can’t shine on it as much. And the further it turns away, the darker it gets, causing a “gradient” or gradual change from a lighter area to a darker area.

So what about those flat objects? Why aren’t they all the same value since they’re not curving away from the light? Well, that has to do with the fact that as you move further away from a light source, the intensity of the light decreases causing it to get darker. 

The gentle curvature and ever-changing angles of a sphere are a prime example of this phenomenon. If you're interested in learning to draw the perfect sphere and becoming a gradient master — here's the place to start!

The next big secret that works together with this idea of always drawing your values as a gradient is...

4. Not only do light colors get darker in the shadows — dark colors get darker. (Also, light colors and dark colors both get lighter in the highlights.)

So, now that you know what a gradient is and how to properly apply it to your drawings, let’s talk about how your values react as they get darker or lighter.

For this one, let’s look at the image below as an example.

The majority of the light on this image is coming from a light source in front of the little boy. If you follow the contour of this little guy’s shirt into the shadow areas, you can see that the white of the shirt is getting darker as it moves further into the shadows.

It’s not surprising to see that the shirt is getting darker because it doesn’t have the light shining directly on it and brightening it up.

At least we’re not surprised that the white parts of the shirt are getting darker. But what about those dark gray stripes? They’re already really dark. So they’re not getting darker, right?

Actually, yes. They will get darker just like the white part of the shirt.

(When we get to secret # 7 below we’ll learn even more about why this happens.)

But let’s look at one more (perhaps surprising) truth about how the visual world is working on our little buddy’s shirt for just a second.

What’s happening to the bright areas of the shirt where the light is shining? Naturally, it will be lighter. And… you guessed it. Both the white and the gray stripes are getting lighter where the light is shining.

As simple (and maybe even obvious) as this may seem, the surprising part is how there are very few would-be artists that employ this powerful concept when putting pencil to paper.

Members of "Art Studio" — Darrel's weekly online drawing class — can click here to see this principle in action now!

Now, let’s discover one more secret that gets ignored over and over again...

5. If something is in front, you can’t see what’s behind it (duh!) — Plus, a bonus.

Here’s where our brain can really play some funny tricks on us!

Sure, it seems super obvious that if something is in front of something else it will hide what’s behind it. But how often have we all tried to draw way too much of that thing that is back there in the background?

Let’s think about ears for just a second. We know — and agree — that if something is “behind” something else it is not going to be seen, right? Good!

So when we’re trying to draw a portrait, why do we so often fool ourselves into thinking that we need to draw the entire ear — even if it’s completely hidden behind hair or partially obscured by a cheek because of the way that the head is turned?

It’s all because another part of our brain kicks in and tells us that we need to draw a full ear there. So we have to “defeat” that part of the brain while we’re drawing and realize we’re only drawing the part of the ear that isn’t being covered up.

See how the lens of the glasses is hidden behind the nose?

How many times have you seen someone draw something like this—but try to move the lens (or whatever else) over so that the whole thing can be seen?

BONUS SECRET: Let’s just take another minute here and look at the cause of another, very similar, problem that most of us run into.

To understand this other problem, let’s now think about the cheeks on a face.

Just like we were discussing about “things hiding behind” a second ago, if someone turned their face to the side, you wouldn’t be able to see one of the cheeks—the one that is “behind” on the other side of the face.

Now if they slowly turned their face back toward you, part of their hidden cheek is going to begin to appear. But you won’t see all of the cheek at once.

In fact, it will just appear narrow at first and then get wider and wider as our friend we’re imagining turns her head further around so that we can see more of the cheek that had been hidden.

Here are some “top down” diagrams to help you see exactly why this happens…

See how the cheek keeps getting more and more narrow as the head turns until you can't see the cheek at all?

The magic of this simple idea is called foreshortening.

Discover how this principle affects the way you see an eyeball as well...

Now let’s discover another secret that may seem super simple on the surface—but is still ignored over and over again when we sit down to draw—to the detriment of our success...

6. If something is blocking a light source, it will cast a shadow — but did you know…?

Easy enough, right? I mean, that’s kind of the definition of a shadow… the absence of light, but it’s a concept that many artists fail to apply.

As you lay down your value, it’s important to analyze your subject and make sure you recognize where you have facial features, articles of clothing, or whatever it may be standing between your light source and another area of your drawing.

When drawing a portrait of a person, the nose is a notorious shadow caster, naturally, since it’s usually the most prominent feature on a face. But, things like shirt collars, glasses, and hair will also create shadows that you need to learn to take into account.

Eye sockets are another biggie! Those finely-tuned eye receptacles cast shadows because they are set back into the face and act as a protective barrier. It’s important to consider this fact as you draw and shade the eyes.

Check out this drawing and see if you can spot all the places that shadows are being cast…

The beard on the shirt, the nose on the mustache, the eyebrows on the eye sockets, the folds in the clothing. They’re all over the place!

Now, here’s a good opportunity to readdress the importance of creating a gradient! Even if you look over your reference photo, locate the shadow casters, and create the shadow on your drawing, you’re not out of the dark yet (pun intended).

Remember, the shadow can’t be all the same value! The shadow is going to be the darkest in the part that the least light can get to, but it will slowly get lighter as it escapes the grips of the object casting the shadow and returns to the light! Failure to create that gradient will leave you with a big blob of darkness that would steal the show—you don’t want that.

That being said, how do you know how dark to go in the areas closest to the object casting a shadow? Do you choose your darkest pencil and press as hard as you possibly can? Let’s talk about that in secret number 7.

7. Every color gives in to peer pressure and changes because of it’s friends

Have you ever looked at your lawn and thought to yourself, “that’s a good looking lawn!” But then you looked to your left and saw your neighbors lawn, lush and green, filled with colorful flowers, every sprig of every plant perfectly aligned.

Suddenly, in the light of this discovery, your lawn looks a little brown and what you were once willing to write off as wildflowers are now undeniably just flowering weeds.

What caused the change?

Well, you had something to compare your yard to. It’s not that your yard is ugly, it’s just that relative to your neighbor, it doesn’t shine quite so bright.

The same is true of value!

Try out this cool test of relative values below by dragging the square with a circle in it over Box 1 and Box 2…

This is an optical illusion that you face in your drawings everyday. In fact, both Box 1 and Box 2 are the exact same color.

Isn’t that wild? Your perception of value was swayed by whether the value around the square was light or dark. This is more than just a fun party trick, it’s an example of how you can use this phenomenon to your advantage.

Use this value reference chart to find where this optical illusion is hiding in your own graphite drawings!

When you draw in your shadow values, there’s no need to press super hard with a super dark pencil. As long as you create a gradient that gets lighter and lighter as it moves toward the light, your shadow value is going to appear darker in relation to the highlight.

So, you can stop damaging your paper by pressing too hard AND you don’t have to buy every B pencil on the market to get the dark values you’re after.

But remember, just like we talked about in secret # 4, if you make one area darker, you have to darken up the entire gradient to avoid creating “heavy” dark areas that stick out like a sore thumb.

So, there you have it!

7 secrets that, when applied to your drawings, are guaranteed to increase depth and dimension and add a life-likeness that gets attention.

The beauty of these concepts is that no matter what media you choose—graphite pencil, colored pencil, pastel, watercolor, etc.—these universal visual principles can be used to improve your artwork!