As a whole, there are two main things that I can see across your work on this challenge. One is that you're demonstrating a vast capacity for patience and care both in terms of observing your reference in order to identify the visual nature of the reference images you're working with and in applying your marks carefully to reflect that - which is a big step up from the 25 wheel challenge work you submitted previously, where my critique largely focused on a lack of patience and care in building up the structural aspect of the work. And the other is that observation and drawing what you see has definitely been far and away the main focus of your work throughout this challenge, which isn't correct - but in the sense that I think using the work you've done here, I should be able to help you better understand the role texture plays in the larger context of this course, and how it can link back more robustly to the core principles of spatial reasoning. So don't be disheartened by that fact. Ultimately the work we do throughout this course is to illustrate to whoever's providing feedback what advice/information can be provided to keep you moving in the right direction.

So basically the big focus of texture in this course is the concept of implicit markmaking and how it can be used to strategically control how much detail is being applied to a given surface or element of a drawing, without changing what is actually being conveyed. This can be very useful when you get into concepts that exist outside of the scope of this course - like composition (although it is something we used to cover, the lesson material for which we have archived here. Composition is basically our ability to guide and control how a viewer experiences an image, in terms of the order in which they see different parts of it, and how they move through it from one "focal point" to the next. The eye is naturally drawn to areas of high detail density (where you've got lots of visual information - in our case that's going to be the areas with the highest concentration of black and white, giving us lots of contrast to grab the viewer's eye), and so simply packing everything with detail ends up being overwhelming and leaves the viewer to navigate that visual screaming in whatever way they can, rather than one that we can direct. Conversely, strategically putting the detail into key areas where we want the viewer's eye, and leaving the rest to be relatively more "restful" can put us in the driver's seat.

The problem is however that when we rely on the approaches to markmaking that we're used to, which I refer to as "explicit markmaking" where we're drawing things directly (so for example, outlining forms whether partially or in their entirety - this is something we tend to do when drawing directly from observation, where we see something and then move to put that mark down on the page as we see it), this works towards a particular end goal: to draw everything that we see, every bit of detail, every structure, all of it. When we inevitably fall short of that, whether because we know we don't want to add quite so much detail or because our arms refuse to respond with the sheer amount of labour it demands, we fall short of our goal, and that is something the viewer can see. That a goal was set, and we failed to meet it. They may not be able to speak to it directly, but they can see it in how the marks that are drawn - in cases like the far right end of this plumage/feather gradient - feel kind of random and arbitrary, like there isn't a particular logic that one can pinpoint in why certain marks were drawn, and others were not.

The solution is to base those decisions off a logical basis that can speak to the viewer's subconscious in a language they understand - and that language is the language of form, of 3D space. And it is for this reason that in these reminders from the texture section we stress that one should not draw what they observe directly, but rather to inject an intermediary step of understanding the forms we've observed, as they exist in 3D space.

When engaging with texture in this course, ultimately we're taking information from source material (our references), understanding the arrangement of forms depicted there, and then using it as a tool for our own purposes. So in this exercise, it's all about the gradient - the far left square is part of helping us to process what it is we're observing (so drawing that part purely from observation is totally okay), but the gradient is about learning how to create, through implicit markmaking (and therefore based entirely on forms we understand), a transition from black to white. The key here being specific forms whose existence in space we fully understand. So cases like this where you employ more arbitrary stippling isn't what we're looking for - we want to consider the forms that are present (that one's strawberry skin, so you'd be dealing with the seeds themselves, as well as the areas around them that rise up). Of course you can use little divets but it's not enough to simply draw a billion little marks because strawberry skin has little pocks and divets in it. You have to design those shapes, outlining them first, based on your understanding of how they exist in space.

At the end of the day, every mark we draw is a cast shadow. So we're not drawing the forms directly, we're drawing the impact they have on their surroundings (the shadows they cast on the surfaces around them). The reason we use cast shadows specifically, beyond the fact that they allow us to link back to spatial reasoning (since the shape of a shadow defines the relationship between the form casting it and the surface receiving it) is because the way they work gives us a tool that is very useful towards being able to transition smoothly, and logically, from areas of high detail density to areas of low detail density.

As shown in this diagram, depending on how far the form is from the light source, the angle of the light rays will hit the object at shallower angles the farther away they are, resulting in the shadow itself being projected farther. Technically as long as there's a raised structure along a surface, a light source that hits that raised structure from a low enough angle will project that shadow as far as we want it to. Similarly, a light source that is close enough will blast away all of the shadows in an area, giving us what appears to be a blank surface. This doesn't strictly mean that we have to worry about all of the specifics about which light sources are where (in the context of what we're dealing with here - it can be important in other cases) - rather, for our purposes here, and to help add structure to implied details we may include in any illustration, we have a lot of flexibility to simply say that because there's a reasonable explanation for why details might be drawn more densely packed in one area, or so firmly in shadow that everything except for the very edges of a given compound shadow shape is plunged into darkness, or so completely in the light that the surface appears blank, that we can be pretty liberal in where we include such areas in our drawings.

It simply all has to be tied together with one common thread: an understanding of what you're drawing as it exists in 3D space, not just at the macro scale of the major structures you're representing (which is what most of this course focuses on), but also at the micro scale of the surfaces themselves. That we cannot simply focus on the result we're after (in the sense of looking at a reference image and then applying it to the drawing directly), but that we must consider everything through a lens of 3D space. And secondary to that, we must also always remember that the forms we choose to represent, as we choose to represent them, is something we control. Every reference we use is a tool, and we only use it insofar as it aligns with the goals we are pursuing. So if we want to adjust the relative heights of the textural forms along the surface of a given object to create shadow shapes that better suit what we're after, then that is entirely within our prerogative to do so.

So in terms of actionable things to alter in your approach to be able to apply what I've explained above better, I recommend the following:

• First and foremost, don't put down any textural marks without allowing yourself to design a shadow shape by first outlining it as explained in those reminders. So for example, as shown here, don't just draw lines intended to stand as whole textural marks. Design complete shapes, then fill them in. I'll explain in a moment why that's so important.

• Secondly, always remember that your light source is on the far right, and so your shadows will be cast to the left.

• Thirdly, make sure that you're not conflating form shading (where a surface gets darker or lighter as it turns towards or away from the light source).

• Don't rely on hatching, stippling, etc. These are the tools that we traditionally use when trying to convey a gradual shifting tone (so for example to convey form shading), and while it is very similar to what we are doing, the key difference is that the marks themselves have no relationship to 3D structures in the scene. So in essence, what we're doing here is like hatching/stippling, but instead of arbitrary marks, we're using specific shadow shapes, allowing them to be packed more densely and merge together the further into the black we go.

• Think about where your shadows might get "trapped" as the light source gets hotter and hotter, blasting shadows away. A good example of this are veins (like those we encountered in our leaves in lesson 3). So if we look at a basic branching vein structure like this, we can see the explicit edges of those veins drawn out. These edges can be divided into areas that are straighter where any shadows being cast by the veins themselves would be more exposed to the light, and "pockets" where different segments of vein meet to branch out, as we see here. In those pockets, shadows can survive longer - due to them being caught in these areas where different forms meet - and so while they too will eventually be blasted away entirely, they'll linger a little longer than the shadows from the straightaways, resulting in the vein texture being represented like this, where only the pockets remain. We can see some examples of this on your corn texture between the kernels, but it's something you've applied less consistently, and because you still relied heavily on drawing lines directly (instead of designing shapes), where you hit the portions further to the right where the lines actually start disappearing, you weren't as able to get your textural marks to taper off very well. This leads us back into why it's so important to rely on outlining/designing shadow shapes, then filling them in, which will round out the end of this critique.

Approaching them in this two step process simply gives us vastly more control over the result. As an approach it has its own weaknesses - it's true that there are certainly going to be shadows that are cast that are so small they can't reasonably be executed using our two step methodology - but in such cases it's better to actually leave them out, for the following reasons:

• A designed shape, despite not being something we can create quite as small as a one-off stroke, tapers in a more nuanced, delicate fashion, whereas a one-off stroke is more likely to end in a manner that feels more sudden. Thus, the shapes lean better into our goal of creating a gradient that transitions from black to white (and ultimately we have to pick a point for the shadows to drop off altogether anyway, so pushing a little farther with singular strokes isn't strictly necessary).

• Drawing in one-off strokes allows us to lean more into drawing directly from observation (as opposed to observing, understanding the forms that we see as they exist in 3D space, then creating shadows based on that understanding), which can be very tempting as it can allow us to create more visually pleasing things without all of the extra baggage of thinking in 3D. But of course, 3D spatial reasoning is the purpose of this course.

More than anything else, intentionally designing shadow shapes in this manner keeps us closer to the goal of ensuring that the student is always thinking about the forms at play, which themselves drive the shadow shape that results. That doesn't mean that designing your shadow shapes will inherently always get you to think about the 3D forms involved, but it's more the opposite - having the freedom to put marks down with less resistance, with less process, simply makes it easier to forget to consider that middle step of "understanding" the 3D aspect of our texture altogether. And so, this gives us a more tangible routine we can adhere to (whereas just trying to remind yourself to think about the forms can be much more tenuous).

Anyway! I'll still be marking this challenge as complete. Its main purpose is to give me an opportunity to talk about texture with a student in-depth, being able to focus on the specific tendencies they exhibit in their work, and using their work as examples where possible to really make the points stick, so you have still entirely met the purpose of the task. Be sure to keep what I've explained here in mind as you get back to the wheel challenge.