Starting with your cylinders around arbitrary minor axes, your work here is somewhat mixed - most of which comes down to the degree you're choosing for each given ellipse relative to the circle in 3D space it's meant to represent. These issues fall into a few specific categories:

• Cases where the degree shift is reversed, resulting in a wider ellipse on the farther end and a narrower ellipse on the end closer to the viewer - for example, 14, 29, 56, 104, 126, 149, to name a few. This is incorrect - the far end should always be wider. This concept is explained here in the cylinder challenge notes, but it's also explained in Lesson 1, in the ellipses section.

• Cases where you attempt to avoid any shift in degree from one end to the other (so both ends end up being about the same overall degree), which we see in 9, 36, 79, 109, 118, 143 - again, just to name a few. Where there are circumstances where you could end up with the same degree on either end, they're not particularly common, and those factors did not play a role in your decision to maintain a consistent degree in these cases.

• Cases where you appear to have avoided any convergence to the side edges, resulting in ends that are the same size (with no scale shift to imply foreshortening). We see this in cases like 34, 42, 64, 71, 84, 133, and many others. This is an issue that is specifically addressed in these notes - that section goes over why this is incorrect.

There were a few other situations that stood out to me, but which didn't exactly fit into a more generalized pattern. For example,

• 97 on this page has the smaller end filled with hatching - it seems like you got a little turned around in terms of which end was supposed to be which, as both ends feature some characteristics of being the end facing the viewer. The upper end has the hatching and is also narrower in degree, but the lower end is larger in overall scale, resulting in the side edges diverging downwards, suggesting that the lower end is closer.

• If we look at 64 on this page, this is probably the best opportunity to discuss what the degree of our ellipses actually means in terms of what's being depicted. The degree of the ellipse corresponds with how the circle in 3D space it's meant to represent is oriented in that space. So a very narrow ellipse tells us that the circle is mostly turned away from the viewer. A very wide ellipse tells us it's facing towards us more directly. Looking at 64, we can see that those ellipses are starting to get into the wider territory, so they're starting to face the viewer more head-on. Not completely, but definitely a fair bit. If however we look at how these circles are situated in 3D space, we can see that there's a fair bit of distance between each end, even though the ellipses are turned more towards the viewer. In such a circumstance, the ellipses should probably be much closer to each other if the cylinder is any kind of reasonable length - in order to be oriented like they are, facing the viewer more head-on, the cylinder itself must have a lot of its length hidden in the "unseen" dimension of depth. While this on its own doesn't tell us that the cylinder is incorrect, if we look at the fact that there's very little foreshortening applied to the cylinder (so the far end is roughly the same in its overall scale, and roughly the same degree), that tells us there is in fact very little extra length in this "unseen" depth dimension - and so we start discovering that this arrangement is implausible, or even impossible, within the rules of perspective. It all comes down to being consistent with what the various visual cues you're giving to the viewer are saying. Is the cylinder long? Is the cylinder short? How are the ends oriented in space? In this case, we'd either have to bring the ellipses closer to one another (even getting them to overlap, in order to reduce the perceived length of the cylinder), or we'd have to make the foreshortening more extreme by making the far end much smaller and much wider (in order to increase the length of the cylinder).

The last thing I wanted to call out in regards to this part of the exercise is that while there are plenty of places where you demonstrate the capacity for good, consistent linework, you have as many sections that suggest that you're rushing, not giving yourself enough time to employ the ghosting method consistently for each mark (both straight lines and ellipses), and that you also sometimes go back over marks to correct mistakes.

It really is critical that you give yourself as much time as you require to do this work to the best of your current ability - that means reviewing the instructions periodically to ensure you're not approaching the exercise incorrectly (especially when tasked with doing the same thing over a long stretch of time), and giving yourself the time you need to execute each mark with care and preparation.

Continuing onto your cylinders in boxes, while you start out with a few notable issues - for example, extending your lines in the wrong direction in cases like 152, 156, 173, and keeping the edges of your boxes too parallel on the page (153, 167, 169) - but there is definitely improvement on this front over the course of the set. This exercise is really all about helping develop students' understanding of how to construct boxes which feature two opposite faces which are proportionally square, regardless of how the form is oriented in space. We do this not by memorizing every possible configuration, but rather by continuing to develop your subconscious understanding of space through repetition, and through analysis (by way of the line extensions).

Where the box challenge's line extensions helped to develop a stronger sense of how to achieve more consistent convergences in our lines, here we add three more lines for each ellipse: the minor axis, and the two contact point lines. In checking how far off these are from converging towards the box's own vanishing points, we can see how far off we were from having the ellipse represent a circle in 3D space, and in turn how far off we were from having the plane that encloses it from representing a square.

This does of course mean that the line extensions are very important - we need to be applying them correctly (ensuring they're extended in the right direction, and that all the lines are extended), and that when drawing the box we need to also be ensuring we're focusing a ton on keeping our edges' convergences consistent. I did see a couple of cases, like 192's blue and green lines, where it seemed like you may not have given yourself enough time to think about how each edge needed to be oriented to maintain more consistent convergences. There were also many more where the lines of a given set would convergen "in pairs" rather than all four together. While nailing this perfectly isn't really what we're after, it is not at all uncommon for students to perhaps be a little careless when it comes to thinking about how each line could be oriented relative to the other lines in its set (both those that have been drawn, and those that have yet to be). In such cases, they end up relying more on random luck rather than the specificity of how their time is invested in their approach.

As you progress through the set of cylinders in boxes, you do improve in terms of your leverage of these elements, and you do shift towards giving yourself more time to think through the constructions of your boxes, and so I similarly see improvement when it comes to your estimation of your boxes' proportions. One area that you are currently missing however, which certainly will help, is to be sure to extend your ellipses' minor axis lines all the way back. Right now you seem to more often be identifying those minor axes similarly to the cylinders around arbitrary minor axes. Here we definitely want to be able to extend them all the way back so we can compare them to the other lines with which they're meant to converge.

So for example, for number 200 on the top left of this page, the little red minor axes should be extended much further, so both can be easily compared at a glance with the boxes' own red edges.

Now, while I am not going to be requesting revisions for the second section, unfortunately I feel you could have done much better with the cylinders around arbitrary minor axes - so I'll be giving you the opportunity to demonstrate that. You'll find your revisions assigned below.