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

Starting with your organic forms with contour curves there is something to call out, it seems you did one page of contour ellipses, though the assignment was for both pages to be contour curves. Not a huge problem, but it does suggest that you may want to be more attentive when reading through the instructions.

It is clear that you're trying to stick to the characteristics of simple sausages that are introduced here, and the majority of your forms are pretty close.

You're also doing pretty well with shifting the degree of your contour curves, which is an aspect of this exercise that often gets forgotten. To introduce more variety into how you arrange your curves, I'd like you to take a look at 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 these are coming along well, you're following the demos carefully, and then applying the construction methods shown in the demos to your own independent constructions quite effectively. You're demonstrating a good grasp of how the forms your draw exist in 3D space, particularly through the abdomen segmentation of some of your constructions which is solid and voluminous.

Overall things are heading in the right direction and I have just a couple of pieces of advice for you to keep in mind when doing these constructional exercises in future.

The first of these relates to differentiating 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.

For example, I've marked on your work 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 most 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 some examples where you'd extended off existing forms using one-off lines or 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. I think you probably had the sausage method in mind for most of your leg constructions, though you don't always stick to the properties of simple sausage forms, and I'd like you to take another look at where to use contour curves when applying the sausage method. We use these contour curves to explain how the forms intersect at the joints, making any additional contour curves along the length of the sausage forms redundant.

It's not uncommon for students to be aware of the sausage method 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 as shown in these examples here, here, and in this ant leg demo and also here on this dog leg demo as this method should be used throughout lesson 5 too.

The last thing I wanted to call out is simply that I noticed a tendency to draw your earlier constructional marks a little more faintly, especially when blocking in the head/thorax/abdomen. Be sure to make every mark with the same confidence - drawing earlier parts more faintly can undermine how willing we are to regard them as solid forms that are present in the 3D world, and it can also encourage us to redraw more, and trace more over this existing linework later on, rather than letting them stand for themselves.

So, that should cover it. You're doing a good job and I'll go ahead and mark this lesson as complete. Please keep the points in this feedback in mind as you tackle the next lesson, they will continue to apply to animal constructions.