Lesson 2: Organic Forms, Contour Lines, Dissections and Form Intersections

As of October 8th 2016, after roughly two years of offering free critiques, I will now be limiting my own critiques to patreon supporters ($3 or more). But don't fret - you are still welcome to freely submit your work and questions directly to the /r/ArtFundamentals subreddit to be reviewed by the community.

If you haven't already, go check out Lesson 1 first. In order to gain the most from these, the lessons should be done in order.

Many of you have already completed this lesson, and I don't expect you to go back and redo the homework. While there will be a few new or different exercises included here, if I've marked this lesson as complete for you, it means that I've seen that you have a decent understanding of the material. The core concepts have not changed at all. I have however added an extra exercise, and I do believe it would be beneficial to give it a shot.

The Basic Mechanics of Drawing: Organic Forms, Contour Lines, Dissections and Form Intersections

This lesson explores the use of 3D forms, and how we can apply some of the techniques and approaches we used in the previous lesson to convey the illusion that what we have drawn on a 2D sheet of paper actually exists in three dimensions.

Part 1: Organic Forms and Contour Lines

Often times when drawing, it will help considerably to reinforce the illusion that an object on the page exists in three dimensions, rather than two. While this can be achieved to varying degrees by incorporating lighting, there are other - potentially more effective - methods that can be used. One of these is the use of contour lines - lines that travel along the surface of an object, and in doing so, describe that surface.

The Uses of Contour Lines

Understanding how contour lines work will influence both how you design elements of your drawing, as well as how you go about rendering it. Costume details, such as seams and layering do a great job of reinforcing the forms underneath, bringing special yet subtle attention to how the object turns through 3D space. Brush strokes and hatching should also be used to reinforce form. Each line or stroke should follow along the surface of the object. Contradicting the surface will have the opposite effect - it will flatten the object out by breaking the illusion.

Using Hatching to Reinforce Form

I find that the way a drawing comes out reflects how the artist was thinking and perceiving the drawing process. It influences the result in subtle, but significant ways. When drawing a 3D form - especially one that curves, like a sphere - I consciously try to perceive the action of drawing along that surface as though I were carving. Instead of a pen gliding along a flat plane, I try to feel the curvature under my pen.

If you focus hard enough, and convince yourself that the object is in fact three-dimensional, you'll find that when you attempt to draw against that surface curvature, you'll feel some slight resistance. That's your brain insisting to you that what you're attempting to do is not possible in the world that it is perceiving.

Ultimately, the first step to tricking your viewer is to trick yourself.

Constructional Contour Lines

Fortunately, tricking yourself can be done through many of the same techniques that are used to trick your viewers. When I sketch an object from observation, I will just about always throw in extra contour lines, wrapping around my forms, than what I actually see in the natural detail. These are not intended to capture any particular element that I can see, but rather they help me to understand how the forms are turning in space.

The vast majority of the time, I'll draw these contour lines in as ellipses. If you remember from lesson 1, an ellipse is the representation of a circle in 3D space. The degree (width) of the ellipse communicates the orientation of that circle in relation to the viewer.

Think of the contour lines/ellipses as cross-sections of your form. In this case, it's a tree, and the branches are quite cylindrical. By using these contour ellipses, I can help reinforce the illusion in my mind that I'm drawing a tube that is winding through 3D space.

You might look at this and think it's messy - and it is, but it really doesn't matter. In doing these observational studies, we are not trying to make some pretty drawing to show all our friends. Instead, we are trying to visually communicate these objects, and thoroughly understand them. This will often require drawing through forms, including lines that you would not generally see. If you ask me, these analytical drawings convey a different kind of beauty - they're not exactly what you see when looking at a tree, but it comes closer to what makes it firm and solid, what makes it exactly what it is.

  1. Organic Arrows

    A lot of you will find that you're rather stiff when it comes to drawing. In later lessons - especially when dealing with plants - this might cause you to struggle, as it is at times difficult to understand how flat objects like leaves and petals can warp and turn through 3D space. These objects represent 2D planes, so sometimes it can feel a little contradictory.

    While flat objects do not carry any weight or solidity like your heavy 3D forms, their essence lies in their fluidity and flexibility. They wrap and curve through space itself.

    For this exercise, we are going to draw arrows. You can also consider them to be ribbons, fluttering in the air, but I believe adding on the directional element of the arrowhead helps emphasize the concept of movement.

    Start off by drawing a curve on the page. You may want to practice these a bit on their own as well. Try to draw a curve that bends and turns a little. S-curves are usually generally pretty good. Put yourself in the mindset of drawing in 3D space - your curve isn't simply sitting on a flat page, it's travelling through the depth of it as well.

    Keep in mind, when parts of a curve in 3D space are further away, they will bend and twist more quickly. Then, as they come closer to the viewer, the curves will be much larger and more gradual.

    Figure 1.5 is an exaggeration, you probably don't want to use such a spiraling curve for this exercise. That said, look at how it is broken down into points that define the curve. Where the curve is further away, more of those points are crammed together into a smaller space - because of the rules of perspective. Things that are farther away are smaller, including the distance between the points.

    Next, draw the same curve a little below it. This can get tricky, since it's quite difficult to replicate an identical curve. You'll notice that in my example, it isn't an exact duplicate, so don't worry if it's a little off. Perspective-wise, technically it should be smaller on the far end and larger on the closer end, but don't worry too much about that, as it might overcomplicate things at this point.

    Now, we connect them and add an arrow head at one of the ends. Fairly straight forward.

    Finally, add a little bit of shading at the bends, and reinforce your overlaps with a bit of extra line weight. A good rule of thumb for applying line weight at overlapping points is that the line that crosses on top gets the thicker treatment, to establish its dominance. Don't go overboard with this though, just make it a little bit thicker. Be subtle.

  2. Organic Forms with Contour Lines

    Now we're going to put those contour lines and contour ellipses into practice. All throughout this exercise, remember one thing above all others: WRAP your contour lines around the forms. Don't simply draw an arbitrary line, actually consider how the curve will go around the form. Drawing those contour lines as ellipses for the first page will help give you a sense of how these lines should wrap around.

    Start by drawing an organic form on the page. Basically, a blob. It may help for it to be more sausage-like in nature, but you can be fairly random with it.

    Next, draw a center line through the form. If you've got multiple pieces branching off, let your center line branch off as well. Try your best to get this line down the center of the form's masses.

    Now, we draw our contour ellipses. Draw a few of them, using that center line as the minor axis. If you didn't quite get your center lines in the middle of the form's masses, you'll have to approximate a bit (as I did in the example). If we were doing this with a cylinder rather than an amorphous blob, the center line would go straight through the spine of the cylinder, and all of the ellipses' minor axes would align to it. If you don't remember what the minor axis is, skip back to Lesson 1 and reread the ellipse section. Essentially, it cuts the ellipse into two symmetrical chunks through its narrower dimension.

    I expect you to spend a fair bit of time practicing this exercise with full ellipse contour lines. Draw them as you drew the ellipses in lesson 1, drawing through them a couple times before lifting your pen to ensure that you get the appropriate shape. As I mentioned there, try to be clean, but the shape takes precedence.

    Eventually you'll be able to draw your contour lines as curves instead of full ellipses. Be sure to wrap them around the form nicely so that they communicate a strong sense of volume and 3D form.

    Here's a short video demo on how to tackle this exercise

These exercises should be done traditionally, using a felt tip pen (0.5mm is ideal). I use the Staedtler Pigment Liners, and sometimes the Faber Castell PITT artist pens (more expensive and higher quality), though there are plenty of other brands that work just as well.

Felt Tip Pens

In a pinch, ballpoint pens can be used, but I strongly advise against using pencils or working digitally for these exercises.

As homework, I recommend doing at least:

  • 2 filled pages of arrows
  • 2 filled pages of organic forms with contour lines; one page with contour ellipses, one page with contour curves

If you want a critique and some direction, you can submit your homework for review as a comment on this lesson's post on /r/ArtFundamentals. If you do choose to submit, please be sure to complete the homework in its entirety (all three parts as prescribed: organic forms, dissections, form intersections) in the required medium/media. While I am happy to help out, it does take a lot of time, and I'd greatly appreciate it if the time is taken to fully read and digest the material.

Part 2: Dissection

The dissections are a whole lot of fun, in general. I could have included them in the previous section, because they are essentially extensions of the organic forms. That said, I'd like to take this opportunity to introduce the use of reference images to help inform our decisions when applying texture.

As I've probably mentioned before our goal here is, rather than creating beautiful pieces of art, to visually communicate the idea of whatever it is we're trying to draw. Form, volume, solidity and construction are all major components of this, but on a secondary level - once all those other things have been sussed out, the next thing that will help communicate our ideas is detail.

All beginners have a whole lot of trouble with drawing detail off the top of their heads, and for good reason. When we just start drawing, we don't actually have any information regarding detail stored in our visual library. What is a visual library? It's the part of our brain where we tuck away all the little bits of information we gather from observing the world around us. We build it up by truly analyzing and studying any and all subject matter. Looking at how trees are made up of branches that split off from one another, off the central trunk. At how a hinge is composed of two components that pivot around a single axle. At how plate armour is composed of a series of articulated layers of metal to allowing for mobility. Everything can contribute to your visual library.

I'm sure you've seen people just regurgitate all of this intricate detail into a drawing without relying on any reference images - this is because they've already looked at the reference and studied it extensively. For now, you will have to rely on looking at photos or live reference material. While the most common method of expanding one's visual library is to study reference, another method I encourage you to try is to incorporate it into your own drawings. To learn to take the information presented there and find the parts that are relevant to you, and transplant them into your own drawing.

Figure 2.1 is an example of how you can use photo reference. I took three pieces of reference to inform different textural areas - the inside was pulled from a kiwi, while the skin on the outside was a combination of a cucumber and an armadillo.

A few things to keep in mind:

  • Never leave anything paper-thin, unless it actually is that thin. In this case, the skin has some degree of thickness, so I was sure to include it in the cross-sectional cut.
  • Mind your focal area. DO NOT apply texture uniformly across the entire surface. Concentrate it where you want to draw the viewer's eye and let it fade out everywhere else.
  • Don't forget about your object's silhouette. Texture does not simply apply in a 2D sense, but it will also modify the silhouette. Notice in some places you can see the armadillo scales poking out in subtle ways, altering the shape of the object's silhouette.
  1. Dissections

    This pinterest board, set up by community member /u/Rybar should serve as a good jumping off point when looking for reference

    You start off with an organic form with contour lines. It's important that you don't start off with any particular design or object in mind. Just start off with a random form, and add contour lines.

    Pick a section of your organic form, between two contour lines. This section will be your point of dissection - imagine that you've cut it out and removed it, and add a bit of weight to the edges to emphasize that they are the edges of the forms, and that the section between them has been cut away.

    Now... stop. Put your pen down. Go find photo reference, or live objects you can look at and study. I've received plenty of homework submissions where people try to use their imagination for this step, and quite frankly it never turns out well. Reason being, your imagination - or what we call your "visual library" - is empty right now. You don't fill it by just knowing certain things exist. You fill it by actively studying those objects, analyzing them in detail and then applying what you've learned about them so as to solidify them in your mind. That's what this exercise does.

    So, grab some photos of objects with interesting textures - anything will do, because literally any and every object has a texture to it. Next, look at the texture closely and identify what characterizes it - start by noting the major visual elements (bumps, spots, scales, any sort of visual aspect that you see repeated in a pattern). Then identify how those elements are organized - are they spread out evenly over the surface, or are they grouped together, or do they merge to form larger clumps?

    Every texture follows a rhythm - randomness does not exist. At its surface, something may appear random, but if you look deep enough, you'll always find some manner of organization and structure. Never scribble or draw randomly. It simply won't look good or capture the texture you're after. Furthermore, refrain from using hatching lines, as they generally aren't present in most natural materials. More often than not, people just use hatching lines as a shorthand for "I have no idea what goes here and I don't really want to take the time to find out."

    Lastly, draw your textures to various parts of the organic form. Remember that you're transferring texture only - leave any form information behind.

These exercises should be done traditionally, using a felt tip pen (0.5mm is ideal). I use the Staedtler Pigment Liners, and sometimes the Faber Castell PITT artist pens (more expensive and higher quality), though there are plenty of other brands that work just as well.

Felt Tip Pens

In a pinch, ballpoint pens can be used, but I strongly advise against using pencils or working digitally for these exercises.

As homework, I recommend doing at least:

  • 2 filled pages of dissections, starting off as random organic forms with contour lines (examples: here and here)

If you want a critique and some direction, you can submit your homework for review as a comment on this lesson's post on /r/ArtFundamentals. If you do choose to submit, please be sure to complete the homework in its entirety (all three parts as prescribed: organic forms, dissections, form intersections) in the required medium/media. While I am happy to help out, it does take a lot of time, and I'd greatly appreciate it if the time is taken to fully read and digest the material.

Part 3: Form Intersections

I'll be honest - this one is hard. If you aren't comfortable with rotating forms in 3D space (like the organic perspective boxes from lesson 1) you may want to try the 250 box challenge and the 250 cylinder challenge first.

Every object is in some way or another constructed through the interaction of five primitive forms:

You'll notice that for some of them, I didn't use the geometric terminology (cube/rectangular prism, sphere, cylinder). The reason is because I want to emphasize the fact that rather than being hard, like something carved from stone, these forms that we have at our disposal are softer, like rubber. We can squish and stretch them as we please.

Furthermore, I say that objects are formed by their interactions - not just jamming two forms together, but also subtracting them. For example, we can subtract the space a sphere occupies from the side of a cube.

This kind of interaction between forms might be a little more familiar to those of you with a 3D modeling background, where it is referred to as a "boolean operation".

As I said, every object is constructed this way, but it is most noticeable on 'hard surface' objects. Vehicles, household objects, buildings, etc. Figure 3.2 is the rough construction of a tank, made up of boxes and tubes.

You'll notice that in the construction, you can see the horizon line, but no vanishing points. As I mentioned in lesson 1, a construction can have tens or even hundreds of vanishing points, one for every set of parallel lines. Because of this, I approximate my perspective, and one trick in doing so is to pay special attention to my horizon line. All of my vertical lines are straight up and down (this is technically 2 point perspective), so I need only worry about the vanishing points that sit along the horizon. Because of this, I can use my horizon line to help approximate my perspective.

Always keep in mind the fact that if you have a line that is level with the horizon, it will run along it. Then, as your line goes further above or below the horizon, its angle will become steeper.

How Forms Intersect

Moving forward, I want to discuss something that a lot of people struggle with - the actual intersections between forms. As I mention later when we get into the actual form intersection exercise, this is the least important aspect of the exercise, and it takes a great deal of time, practice and study to get your head around. All the same, I'll discuss a few key points that may (or may not) clarify part of it. I warn you now - things are getting technical. Try your hardest to think of these forms in 3D space, as if you could move them around in front of you, and if you don't get it immediately, don't worry and just keep moving forward.

In figure 3.3, you see an intersection between a cylinder and a flat plane. I'm skipping over intersections between two flat objects, because the bulk of the confusion comes from rounded objects.

The most confusing aspect of intersections is understanding where one form is in front of another, and where it is behind it. I will be referring to this quality as dominance, where a form is dominant when it is the one in front, or closest to the viewer, at that given location. The nature of an intersection is just that - the passing of dominance from one form to another. If one of the two forms in question were to always be dominant, then there would be no visible intersection - that form would always be in front of the other.

So, if you look at figure 3.3, it's a lot like a hole-punch going through a sheet of paper. The cylinder penetrates straight through the plane, and so hole left by the intersection is a very simple cross-section of the cylinder itself: it's a circle.

For the majority of this intersection, the cylinder is dominant - except for the area shown in purple, where the plane cuts out in front of the rear section of the cylinder.

Next, in figure 3.4, we see a similar set up - the only difference is that we've put the plane at an angle to the cylinder. Surprisingly, this doesn't change a whole lot - the only difference is that the cross-section slice of our cylinder that we use to determine part of the intersection is no longer a circle. Instead, we take a slice at the same angle as the surface with which the cylinder is intersecting.

The easiest way to think about this is to picture a cylinder in your mind. First, imagine cutting it straight across. Then, imagine cutting it at an angle - the resulting surface is going to be stretched and elongated.

Just as before, the cylinder is dominant for the majority of the intersection, except for the far right side.

So, we've determined that intersecting a rounded object with a flat surface is still fairly simple. The trouble comes when you intersect two rounded forms together. In figure 3.5, you see a cylinder intersecting with a sphere.

I know I've covered this one with notes, but don't let yourself get overwhelmed - just analyze it piece by piece.

The tricky part about intersections between rounded forms is that the passing of dominance from one form to another is not clean and immediate. When doing so with a flat object, you can see the exact point where that dominance changes, because you have a stark change in the angle of your intersection. With rounded forms, that shift is gradual, blending from one to the other with curves instead of hard angles and straight lines.

Look at the area highlighted in blue first - here we're following a cross-section of the cylinder, because it is dominant. As the blue section ends, the curve turns gradually towards following the cross-section of the sphere.

Finally, in the green section, we follow the sphere which is now dominant.

And here is the resulting intersection. Notice how the intersection line is a wave, smoothly transitioning from the contour of the cylinder to the contour of the sphere as dominance is handed off between them.

  1. Form Intersections

    Before tackling this exercise, there's something I want you to acknowledge: The specific aspects of how to handle intersections outlined here are not entirely correct. I have vastly simplified them, and this is completely intentional. This is for two reasons:

    • Proper intersections can get very complicated. A student at this stage could easily become overwhelmed.
    • This exercise is, in all honestly, not really about the intersections. It's about being able to arrange forms together in 3D space. Ultimately that is what I gauge when critiquing homework submissions, though general intersection mistakes would also be pointed out. Still, that should not be your focus.

    So, while some of you may feel the desire to open up a 3D modeling program and test out the intersections yourselves, know that the results may be different, and you may end up confusing yourself far more than you need to.

    Anyway, moving on...

    In principle, this exercise is quite simple. In practice, it's a whole different story - just about everyone has trouble with this one, to some degree.

    Basically, you draw a bunch of forms on the page, and these forms will intersect with each other. You're not constructing anything, so don't try and build it into recognizable forms. Just be abstract. Stick a ball on the end of a tube, jam a box into it, and cut into it with a cone. Anything goes.

    You start off with a box. Well, you can choose whichever simple form you like, but in honour of the name of this website, we're going to use a box. It also helps that it's the most versatile form we've got, and it effectively summarizes 3D space by its very nature.

    If you're having trouble drawing boxes without explicitly drawing your vanishing points, you should look into the 250 Box Challenge before attempting this exercise.

    Be sure to draw through your forms - that is, include the lines that exist on the opposite side of the form, that we technically wouldn't be able to see. This will help you get a clearer understanding of how that form sits in 3D space. I will warn you however that this WILL make your boxes harder to understand visually, so you should absolutely thicken the "visible" lines to make things a little clearer. Adding a little line weight to the silhouette of the form also helps.

    Do NOT use underdrawings. In the past, people have attempted to make things easier by roughing in the forms in pencil, or even with the same pen, before going back over them to "clean up" their line work. This is a bad idea, as it encourages you to be wasteful with your rough lines, and then causes you to be overly careful with your clean-up lines, which ruins the flow and confidence of your marks. Instead, every mark you put down should be done so using the ghosting method - everything should be planned and thought through, and ultimately executed with confidence. You can later go over your lines to add more line weight, but there's a difference there - you're not replacing the lines, you're adding thickness to them.

    Now, draw another. This is where the meat of the exercise comes in. Your primary goal here is to draw a bunch of forms that all look and feel consistent. That is to say, they all feel like they belong together in the same space and scene.

    When two forms don't feel consistent, it's because their rate of foreshortening - how quickly a form shrinks or grows as it moves further away or closer to the viewer - are not the same. One box may get smaller REALLY quickly (dramatic perspective/foreshortening) and another may barely change over the length of its form (shallow perspective/foreshortening).

    So, the goal of this exercise is to learn how to make your forms look and feel as though they should exist together in the same scene.

    For now, I strongly encourage you to avoid forms that are stretched in any one dimension. For example, long tubes, long boxes, and so on. At this point it is far better to stick to fairly "equilateral" forms. That is, forms that are roughly the same size in every dimension.

    Now we can explore other forms. If you're still feeling shaky with your boxes (which is perfectly acceptable), you can do entire sheets of only boxes. In fact, that's actually a pretty good idea, since as I said before, a box is the most versatile form. If you can draw boxes consistently, then you can construct any other form within the space enclosed by that box.

    When dealing with any ellipse-based forms, always start with the minor axis. If you don't remember what a minor axis is, jump back to the ellipse section of lesson 1 for a quick refresher.

    Figure 3.9 includes a really quick breakdown on how to draw a cylinder, along with points to keep in mind (always keep your minor axis centred in the cylinder, and keep the degree of your far end ellipse larger (wider) than the end that is closer to the viewer). If you feel you need more practice (and I assure you, you probably do) with cylinders and ellipses, head on over to the 250 Cylinder Challenge.

    Now, fill up the whole page with forms. I mean it, fill up the whole damn page. People tend to submit homework that has tiny groupings of two or three intersecting forms. I want to see an ENTIRE page of forms all layered on top of each other. It will get visually confusing, but push through it, and use line weight to emphasize certain lines over others. Remember that you have a repertoire of 5 simple forms - boxes, tubes, balls, pyramids and cones.

    Also, don't forget to draw through your ellipses, and to apply the ghosting method. The ellipse thing goes double for spheres, because if your circle is at all uneven, it will not read as a sphere.

    Lastly, avoid drawing forms that are half off the page, because they don't end up teaching us a whole lot. So, I expect to see a heavy concentration of forms around the centre.

    Now that you have filled in your page with forms, you can now try giving some thought to how those forms intersect. In the lesson section above, I discuss how we approach intersections between forms - specifically using rounded forms, because they're tricky. Be sure to check that out.

    Just remember - I do not expect you to nail this. Form intersections are not simple by any stretch, and they take time and work to truly understand. Give it a shot, and even if it doesn't turn out well, keep moving forwards. I fully expect you to continue practicing this even after I've marked the lesson as complete, so you will have the opportunity to continue working at it as you move forwards.

    Luckily, this stuff doesn't come into play until lesson 6 and 7, and in those lessons the intersections we use are considerably simpler than these.

  2. Organic Intersections

    Honestly, I find this one kind of relaxing. The purpose of this exercise is to encourage you to think about the weight and flexibility of your forms in a way that the previous exercise doesn't quite manage. Essentially, we're going to drop a bunch of squishy, malleable organic forms on ontop of each other. If you're still struggling with contour curves and getting them to wrap around forms convincingly, you may want to practice those a little more before attempting this one.

    To start with, draw a simple organic form. Since we're going to be dealing with a lot of them, the complexity of each individual form is not particularly important. It's generally best to stick to something simple, like a sausage form.

    Next, just like in our organic forms with contour curves, and even in our dissections, we add contour lines to give the form volume and form. As you complete this step, think about what it is you're doing - you're not just drawing lines on a page. You're imbuing a flat shape with volume, with weight, with solid form. It's no longer just a 2D shape, but a 3D object that can be lifted, moved, thrown and dropped. If you pick it up from one end, it will dangle. If you hold it from its middle, it will sag on both sides.

    Don't move ahead until you can feel it in your mind, that this form has real weight to it.

    Now we're going to test this idea. Imagine that you had another dangly sausage form, and that you dropped it on top of the first. Consider how it would fall, how it would be held up in one place, and sag in others. Consider how it would conform to the mass beneath it.

    All there is to do afterwards is repeat the process. You can drop more organic forms on top, or you can play with wrapping them around each other, or jamming them into one another. It's completely up to you.

    The important thing is what I've stressed thus far - you're not pasting flat shapes on top of each other, you're dealing with solid forms that cannot occupy the same space. So, in order to wedge them against one another, one has to displace the other.

    Much of what we tackled in the form intersections is at play here as well - the only difference is that our forms are more malleable and flexible. When two of these forms intersect, they displace each other as I mentioned, but you still experience a dominance of one form over another, and that dominance is still handed off between them at different points in space.

    This kind of exercise can be quite calming, once you get the rhythm and the sense of form and mass. Once that clicks, it's just a matter of dropping form after form after form. In the long run, you will also find this exercise to come up when you start dealing with topics such as drawing insects, or drawing animals.

    Lastly, don't forget to play with line weight - we're adding contour lines to everything, so it's inevitable that the drawing will get cluttered and complicated. Not messy, because we're putting thought and planning behind every single mark we draw, but there's going to be a lot going on. So, we draw separate and organize our marks by increasing the weight of certain lines. This pulls them forward, attracting the viewer's attention, which in turn causes the other lines to recede and vanish.

    To extend this concept of line weight, you can also use shadows that extend from those lines to help separate forms and increase the sense of depth. Use this sparingly however, and don't scribble or use hatching - actually fill in the shadow shapes to ensure that you don't add too much contrast to these areas.

These exercises should be done traditionally, using a felt tip pen (0.5mm is ideal). I use the Staedtler Pigment Liners, and sometimes the Faber Castell PITT artist pens (more expensive and higher quality), though there are plenty of other brands that work just as well.

Felt Tip Pens

In a pinch, ballpoint pens can be used, but I strongly advise against using pencils or working digitally for these exercises.

As homework, I recommend doing at least:

  • 4 filled pages of form intersections, done freehand (examples)
  • 1 page of organic intersections

If you want a critique and some direction, you can submit your homework for review as a comment on this lesson's post on /r/ArtFundamentals. If you do choose to submit, please be sure to complete the homework in its entirety (all three parts as prescribed: organic forms, dissections, form intersections) in the required medium/media. While I am happy to help out, it does take a lot of time, and I'd greatly appreciate it if the time is taken to fully read and digest the material.