Tiếp tục dịch phần 3 một bài viết rất hay của Monika Zagrobelna
7. Thêm màu vào bản trắng đen có sắc độ không phù hợp
I painted this picture in 2011. This is certainly a nice, heart-warming scene, and I still quite like it. I remember I painted it in grayscale and then added colors using probably a few Blend Modes (Color, Multiply, Overlay). I remember having this one annoying problem: how to get a proper yellow when painting over grayscale?
I don't have the original file any more, but this is how the grayscale version looked, probably. Notice that both green and yellow areas are equally dark. This is not true in reality!
When I was a beginner like you, I believed that light makes all the colors uniformly brighter, and shadow makes them uniformly darker. That's why painting in grayscale seemed so convenient. I could have focused on shading, and added colors later. Unfortunately, this trick didn't work, and it took me a long time (mainly because I didn't really try) to understand why.
The simple answer is different colors have different brightness independent from lighting. When you ignore it, you get muddy colors as a result. Colors you add directly to a picture in grayscale are devoid of an important part of them. If you want to learn more about it, I've written a complex tutorial on the topic of value.
Both heads have the same colors applied with Color mode. Notice it's not the coloring layer, but what's beneath that matters
8. Shading With the Dodge and Burn Tools
The Dodge and Burn Tools are one of the beginner's favorites. They fit nicely the belief that Photoshop is a "painting program". You only need to choose the base colors, and then select the areas you want to shade. The rest is controlled by advanced algorithms, not by you, and that's great, because you wouldn't know what to do anyway.
However, it's not that easy. These tools aren't completely useless, but when you're a beginner, it's better to stay away from them. They're not "shading tools". The Dodge Tool isn't equal to "add light", and the Burn Tool isn't equal to "add shadow", either. The problem is they fit a beginner's vision about shading so neatly that it's hard to overcome the temptation.
The problem doesn't lie in the tools, but in a misunderstanding of shading itself. Beginners often think that objects have some color, and this color gets darker in the shadows, and brighter in the light. It's not that simple. It may work well for cell-shading, or for cartoon purposes, but even there this is just a shortcut.
If it "kind of" works, why not just use it?
- It's another technique that blocks your progress. When using it, you don't even notice what you're missing. Shading is a complex issue, and you limit it to the "darken-lighten" rule, because it's easy. Photoshop is here to work for you, not instead of you. Don't let it stop you from learning.
- It flattens the shaded object. No matter how many textures you add to it afterwards, it works just like a big brush—which means you can start a picture with it, but never finish it this way.
- It misrepresents the colors; they should be dependent upon the environment (direct light, ambient light), but neither the Dodge Tool nor the Burn Tool knows anything about the background you're using. They shade everything the same way!
Shading With Black and White
The extension of this technique is shading by using white for light and black for shadows. This comes from a belief that every color starts as black (in the shadow) and ends as white (in the light). While it may be true for over- or underexposed photographs, it shouldn't be a rule used in painting.
We all search for simple rules, something easy to remember and use. But it doesn't mean we should invent simple rules that have nothing to do with reality, like: "add white to make it brighter, add black to make it darker". This one is true only for grayscale! If you want to learn what rules you can use to shade with colors, see this article.
Unvaried Shading
When you overcome the previous problem, you may fall into another one. Let's say you've chosen orange as the base color for your character. You decide that the light source will be yellow, and the ambient light will be blue (sky). According to this, you shift the hue of the base color to yellow in the light and blue in the shadow, and that's all. It makes shading much more interesting than if you used black and white, but it's still a shortcut that doesn't necessarily lead to the desired results.
(img) digital painting how to shade boring shading cold shadow warm light
Why is it a shortcut? By creating only three basic shades for your object, you automatically place it in an artificial environment, where everything is reflecting light in a 100% predictable way.
In reality, light continuously bounces off everything around, including the "hills and valleys" of your 3D object. Therefore, shading rarely can be limited to two or three colors. The blue of the sky can make some shadows on the object blue, but in some other crevices they may look greenish because of the light reflected from the grass. Moreover, some shadows may be actually bright and saturated because of light that came through the obstacle into the "shadow" (see subsurface scattering).
If you take this into account and decide to use indirect light sources to make the shading more varied, you'll be forced to paint more deliberately—and that's great! You can't use a big brush here, because it would mix the colors and you'd lose them as a result. And a small brush means you're creating a texture on the fly!
9. Blending With a Soft Brush
There are two main methods beginners use to blend shades, both designed for quick effects:
- Blending with a soft brush
- Blending with the Smudge/Blur Tool
As we've already learned, quick effects often mean they're out of our control. In this case, blending with big strokes flattens the object and makes it unnaturally smooth. Even if you add a photo texture afterwards, it will not take that "plastic" effect away. Again, this method may be good only for that starting phase.
If you want to get a nice subtle texture (which is good for most of the natural materials), use a harder brush with Flow controlled by pen pressure (the harder you push, the more solid the stroke).
This kind of brush lets you control the amount of color you want to use.
Thanks to this attribute, you don't need to blend the border between two colors. You just start with the base color and cover it lightly with the other one. Then you can add another layer of the same color, making it more solid.
If you want to make it smoother, just pick a color somewhere in between and paint lightly over the border.
For a stronger texture, use a textured brush (with rough edges).
According to the 80-20 rule, don't bother about blending in the first phase. Use a big brush, and make the edges apparent, creating an exaggerated shading.
Later you can use a smaller, textured brush to blend the edges. No Smudge Tool, no soft brush, just the Eyedropper Tool and your hard brush with variable Flow. Remember: blending depends on the texture of the surface, so you can't use the same way of blending for every material!
10. Using 2D Textures for 3D Forms
Photo textures are a beginner's last resort, when the object is theoretically finished, colored and shaded, but it still looks like a plastic toy. However, a texture itself may make it even worse.
Let's say we want to add a texture to this big cat.
The object must be shaded before adding textures. The tricky part is it doesn't need to be a complete shading. The method of blending depends on the texture—if you blend without having any texture in mind, you'll get a non-texture blending (smooth surface).
You can download a texture from the Internet, or use one of the Photoshop patterns—there are lots of them in the default sets. This is my favorite pattern for scales, inverted Screen Door.
If you change the Blend Mode of the texture to Overlay, you'll see it applied to the shading. However, notice that some parts have been brightened. You may like it if shading wasn't done properly, but it's another case of giving up control. In most cases, we don't want the texture to create its own version of shading. While the Overlay mode isn't the best solution, it lets you see how the texture looks on the object.
Now, the most important and overlooked part. If the object is meant to be 3D, it can't be nicely covered with a 2D texture. We need to adjust its shape to the form it covers. There are three main ways to do this—experiment and find your favorite:
- The Free Transform Tool (Control-T) in the Warp mode
- Filter > Liquify
- Edit > Puppet Warp
The Overlay mode brightens the parts of the layer covered with white areas of the texture. We could use Multiply instead (it makes white areas transparent), but it would make gradual tones (grays) darker than necessary. There's another tool perfect for adjusting a texture's transparency.
Double click the layer and play with the Blend If sliders. In brief, you can adjust the transparency of white and black with them.
We need to understand what a texture really is. It's not a "rough pattern" placed right on the object. It is, actually, the roughness of a surface. When light hits a smooth surface, it's reflected uniformly. If the surface is rough, i.e. made of tiny bumps and crevices, the light hitting it will create a whole set of tiny shadows. And that's the texture we see.
Another fact can be derived from this. If it's light that creates visible texture, there can be no texture without light. And what is shadow, if not lack of light? Therefore, we need to reduce the texture in dark areas (if there's ambient light present), or remove it at all (no light, no texture). You can use the Layer Mask for it, or play with the Blend If sliders (the second row). Keep in mind that the crevices of texture are in fact shadows, so they shouldn't be darker than the "normal" shadow area.
Applying a texture is fast and easy once you know what actions to take after choosing one. However, this is not the end. Every texture is different, and while some of them will look great when applied directly, most require some more work.
Again, the 80-20 rule applies here. Adding a texture is easy, but making it work is what takes the most time. In my example I've blended the shading edges with individual scales. Things like this are very time consuming, but they change everything!
Conclusion
As we noticed, most of the beginner problems come from that urge to achieve great things effortlessly, as quickly as possible. So it's not really about lack of skill—rather, it's about that deep belief that Photoshop is an art-making program. That leads to a constant search for tools and tricks, instead of making the effort to understand and solve the problem.
You can't become a digital artist in one day, only because you've purchased an advanced piece of graphics software. Photoshop is just a tool—more convenient to use than pigments and brushes, but it's still a tool. It can't do more than you intend it to! If you want to make the best of it, treat it as a digital canvas with digital colors. Forget about all these fancy tools, filters, brushes, or Blend Modes. Just paint, as you would on a real canvas.
Learn color theory, perspective, anatomy—all these things that "normal" artists must learn. With time you'll understand how to use Photoshop's tools to do the same things easier and faster—but don't put the cart before the horse by trying to get great effects without understanding them. Patience is the key!
And although this article has been about developing skills rather than relying on technological solutions, you can still find some useful Photoshop resources over on Envato Market.
