Hello Zaverose, I'll be the teaching assistant handling your lesson 4 critique.

Starting with your organic forms you've done a pretty good job of sticking to the characteristics of simple sausages that are introduced here.

There are a couple of points to note:

• With the form at the top left of this page you've drawn the central flow line completely straight and rigid. This isn't necessarily a mistake, but it is worth pointing out that part of what makes these organic forms so useful is that having a subtle curve along their length allows us to give them a sense of gesture.

• On the same page, with the form in the middle of the bottom row, you've drawn it getting smaller as it gets further away. This is indeed how perspective works, but for the purpose of this exercise we'd like you to keep both ends the same size, and a consistent width along the form's length.

It is good to see that you've included some variation in the degree of your contour curves, although you seem to rely predominantly on flipping their direction to show a form with both or neither ends facing the viewer. Keep in mind that the degree of your contour lines should be shifting wider as we slide along the sausage form, moving farther away from the viewer. This is also influenced by the way in which the sausages themselves turn in space, but farther = wider is a good rule of thumb to follow. If you're unsure as to why that is, review the Lesson 1 ellipses video. You can also see a good example of how to vary your contour curves in this diagram showing the different ways in which our contour lines can change the way in which the sausage is perceived.

Moving on to your insect constructions you're demonstrating a good grasp of how the forms you draw exist in 3D space, with examples like this bee having a very clear sense of the head being in front, with the thorax and abdomen receding in space. The segmentation on the abdomen reinforces this illusion too, it's pretty well done. You've also done a good job of drawing through most of your forms in these constructions, which is great, by including the parts of forms that are not visible in the reference and figuring out how all these pieces fit together this will help to reinforce your understanding of 3D space.

Something that jumps out is about half of these constructions have much fainter lines in the early stages, which has made it necessary to come back with a darker line and reinforce or replace the lines you want to keep visible. If we take this mantis as an example there appear to be two different drawings occupying the same space. There's a faint underdrawing, which has either been done with very light pressure or a different pen, then the "real" drawing has been done over the top with rich dark lines. Notice that we could remove or erase the faint lines and it would not affect the final drawing. This is something Uncomfortable refers to as a clean up pass and while it is a perfectly valid method of drawing in general, it is something we firmly discourage in this course. When students draw their first steps more faintly it tends to make them think of their initial volumes as less real, or less important than the final result, and makes them more likely to undermine the solidity of their forms.

This brings me to the next point I wanted to talk about, on how to differentiate between the actions we can take when interacting with a construction, which fall into two groups:

• Actions in 2D space, where we're just putting lines down on a page, without necessarily considering the specific nature of the relationships between the forms they're meant to represent and the forms that already exist in the scene.

• Actions in 3D space, where we're actually thinking about how each form we draw exists in 3D space, and how it relates to the existing 3D structures already present. We draw them in a manner that actually respects the 3D nature of what's already there, and even reinforces it.

Because we're drawing on a flat piece of paper, we have a lot of freedom to make whatever marks we choose, but many of those marks would contradict the illusion you're trying to create and remind the viewer that they're just looking at a series of lines on a flat piece of paper. In order to avoid this and stick only to the marks that reinforce the illusion we're creating, we can force ourselves to adhere to certain rules as we build up our constructions. Rules that respect the solidity of our construction.

For example - once you've put a form down on the page, do not attempt to alter its silhouette. Its silhouette is just a shape on the page which represents the form we're drawing, but its connection to that form is entirely based on its current shape. If you change that shape, you won't alter the form it represents - you'll just break the connection, leaving yourself with a flat shape. We can see this most easily in this example of what happens when we cut back into the silhouette of a form.

I can see this happening on a number of constructions, for example, I've marked on your ant in red where it looks like you cut back inside the silhouette of forms you had already drawn. One thing I did notice is that many of the instances of cutting into forms (though not all) came down to the fact that your ellipses would come out a little loose (which is totally normal), and then you'd pick one of the inner edges to serve as the silhouette of the ball form you were constructing. This unfortunately would leave some stray marks outside of its silhouette, which does create some visual issues. Generally it is best to treat the outermost perimeter of the ellipse as the edge of the silhouette, so everything else remains contained within it. This diagram shows which lines to use on a loose ellipse.

On the same image I marked in blue where you'd extended off existing forms using partial, flat shapes, not quite providing enough information for us to understand how they actually connect to the existing structure in 3D space.

Instead, when we want to build on our construction or alter something we add new 3D forms to the existing structure. Forms with their own complete silhouettes - and by establishing how those forms either connect or relate to what's already present in our 3D scene. We can do this either by defining the intersection between them with contour lines (like in lesson 2's form intersections exercise), or by wrapping the silhouette of the new form around the existing structure as shown here.

This is all part of understanding that everything we draw is 3D, and therefore needs to be treated as such in order for both you and the viewer to believe in that lie.

You can see this in practice in this beetle horn demo, as well as in this ant head demo. You can also see some good examples of this in the lobster and shrimp demos on the informal demos page. As Uncomfortable has been pushing this concept more recently, it hasn't been fully integrated into the lesson material yet (it will be when the overhaul reaches Lesson 4). Until then, those submitting for official critiques basically get a preview of what is to come.

The next thing I wanted to talk about is leg construction. It is good to see that you're trying to stick to the sausage method, and using it quite well. It's not uncommon for students to be aware of the sausage method as introduced here, but to decide that the legs they're looking at don't actually seem to look like a chain of sausages, so they use some other strategy.

The key to keep in mind here is that the sausage method is not about capturing the legs precisely as they are - it is about laying in a base structure or armature that captures both the solidity and the gestural flow of a limb in equal measure, where the majority of other techniques lean too far to one side, either looking solid and stiff or gestural but flat. Once in place, we can then build on top of this base structure with more additional forms.

I can see that you've jumped right in with building onto your leg constructions with additional forms, although there are some approaches to building up structure on top of those base sausage armatures that work better than others. While it seems obvious to take a bigger form and use it to envelop a section of the existing structure, it actually works better to break it into smaller pieces that can each have their own individual relationship with the underlying sausages defined, as shown here. This can also be applied in non-sausage situations, as shown here. The key is not to engulf an entire form all the way around - always provide somewhere that the form's silhouette is making contact with the structure, so you can define how that contact is made.

We can see how this can be taken further with ant leg demo which shows how we can use additional forms to capture all the complexities of that kind of structure. I'll also share this dog leg demo which shows how this strategy can be applied to animals, as this method should be used throughout lesson 5 too.

Conclusion

All right, I think that covers it. You're doing a good job and I'll go ahead and mark this lesson as complete. Please keep the points discussed here in mind as you work through the next lesson, they will apply to animal constructions too.