PAINTING BASIC SHAPES IN PHOTOSHOP
When you go to art school or simply take a course on drawing you will find that you will often have to draw the basic shapes: a cone, a sphere, a cube, and a cylinder and there is great reason for this exercise. As you progress through your drawing you are going to find that the human body, a fan, a car, whatever you see is comprised of variations of these shapes. Understanding how to simplify these complex real life objects into shapes is very important to be able to accurately create a successful image.
Unlike traditional drawings where you have to learn how to fully control your arm to form straight lines and perfect circles you can call on the aid of digital tools to help you and speed up your workflow. Speed becomes very important if you transition into the working field. We aren't going to do a comparison on digital and traditional. They are both important and as you progress as an artist you will find you will probably begin to utilize both mediums.
With a basic understanding on the importance of these basic shapes we can begin!
By clicking and holding on the dotted box (default) in the top of your toolbar you will get an extra window that will show up that contains other shapes. We are going to use these as somewhat of a stencil.
Let's start by creating a new layer in Photoshop.
With your new layer added we are going to select the circle marquee tool and simply drag a circle on the new layer. By holding shift, you will get a perfect circle that drags from one edge, if you push shift and alt you will drag a perfect circle from the center.
Go ahead and fill this circle with gray. Since I am working on a light gray already I'm going to chose a gray that is a little darker than the background. Don't worry, we can adjust the values later if we need to. To do this, select the paint bucket (if you can't see it, it's hidden under the gradient tool. Click and hold to get the fly out menu). Alternatively you can also push Command+Delete or Option+Delete depending on what color you have set to foreground or background fill. Experiment with them both to see the difference.
LOCK TRANSPARENT PIXELS
Now we have a circle in our canvas and filled we are now going to lock the transparent pixels so we don't have to work around the marquee's ant trail. What this option does is only allows us to paint on the currently existing pixels and only up to their current opacity. Since we don't have any soft edges on this we don't have to worry about the opacity but it will help us with the bounds of the sphere.
Click this little checkerboard image in your layers pallet to lock the pixels. Now we don't have to worry about painting outside of our sphere but if you have a sphere with soft edges it will match the transparency of the pixels. I will include and example.
From here it is helpful to have a little understanding of value. Value is the most important aspect of how we see and perceive the world around us, it is how one color is set apart from another. It is why we can understand a black and white photograph just as we would a color photograph and so on. By simplifying the values down to five we can now start to understand the differences of one value to the next.
Our eyes can see infinite value but we cannot understand that for a drawing, we must simplify and build up as our understanding grows. For instance, here I have a texture I shot, in color it is hard for us to make sense of it immediately.
In gray, we still see it as the same rock wall but it has tremendous amounts of value that we still have trouble understanding.
What we want to do is break it down to five values. Highlight / Light Side/ Mid Tone / Shadow Side / Cast Shadow. This is a way that our brain can begin to comprehend what we are doing and then we add more and more blending to it until you know longer see the simple value breakdown.
I believe this will make more sense by actually attempting the exercise than just reading about it. With experience as our best teacher, often it's while you are working on your project that it will click and suddenly make sense.
PAINTING A SPHERE
Now we understand value and the tools we are ready to start painting. First we want to separate the sphere into a light side and a dark side. Though we want to think in the five values, we will use a soft brush to get our even tones. Let's choose a gray that is about a 70% shade. That will be 0% 0% 20% in a HSB slider.
And now with our light and dark separated, I like to put in the cast shadow as well. This will be the same value as your core shadow. Let's put in on a separate layer as well. Let's start with using the marquee for the shadow and we will adjust from there.
Since shadows are sharper at the source and fade as they get further back, we are going to duplicated the shadow, use Filter>Blur>Gaussian Blur to get the soft edges and then use a layer mask to blend them.
So, let's make a copy of the shadow, drag the shadow layer down on top of the new layer icon in the layer palette and you will get a copied layer. Now go to Filter>Blur>Gaussian Blur. Now the shadow side is slightly blurred, we are going to make a layer mask to get the source area sharper.
After you click on the mask button you will see a new box show up beside your image in the layer palette. We paint white or black in this box to show or reveal what is under the layer. Here is what my layers look like after I have masked them to what I feel is appropriate.
Now we will start to add in the varying degrees of light. I always like to work shadow sides first so I'm going to add in some reflected light. You can see my previous tutorial Blending Color in Photoshop if you need to learn to sample colors and blend them.
We just worked with a 70% shade to do the core and cast shadows so we are going to lighten in just a little to get our reflected (bounced) light that would hit the ground and bounce up onto the sphere. I used the 75% shade for this. HSV 0% 0% 25%.
The previous value on the sphere is serving as a pretty nice mid tone so we are simply going to use a soft brush and lighten the value from the local color and add some light onto the sphere.
Now lets choose our brightest color and add a small highlight and you will suddenly see much more roundness to your sphere after you add the highlight. Don't use 100% white and likewise, don't use 100% blacks in the shadows either. I used a 5% tint for the highlight.
And there you have it. Now to finish this off we are simply going to go back and soften some edges and try to lose some edges. We will probably also add some sort of horizon line in the background just for variation. This wasn't a landscape or similar so it doesn't matter adding it at this point but it's very important to get early on for landscapes.
Don't forget to uncheck the layer transparency lock if you are softening the sphere edges.
Let's go ahead and finish this up!