I have both good news, and bad news. The good news is that the section you found to be tough, the cylinders in boxes, was okay - there are some issues I'll bring to your attention to help you better use this exercise going forward, but no revisions will be required there. The bad news however is that unfortunately you appear not to have taken as much care in following the instructions for the cylinders around arbitrary minor axes.

Looking at this first section, your cylinders around arbitrary minor axes appear all to be drawn such that their side edges remain parallel to one another on the page, without any convergence, suggesting that the vanishing point for those edges were forced to be at infinity. This eliminated the foreshortening for the cylinders, which expressly goes against the specific instructions present here in bold (that is, to include lots of variety in your rates of foreshortening throughout this section of the challenge). More than that however, forcing those vanishing points to infinity is actually incorrect in general, rather than merely missing one of the instructions.

When drawing a form, we do not decide where the vanishing point will go - rather, we decide how we want the given form to be oriented in space, and it is this which determines where the vanishing point should fall. There are a limited set of orientations for a given set of edges that will place the vanishing point that governs them at infinity - specifically it'll occur when those edges run perpendicularly to the viewer's angle of sight. To put it more simply, when those edges run straight across our field of view, without slanting towards or away from the viewer through the depth of the scene.

Given that this challenge, like the box challenge, has us rotating our cylinders randomly in space, we can with confidence say that the likelihood of that perfect of an alignment to the viewer is small enough that in a sample size of 150 it is unlikely to occur at all. In such situations, it's best to ensure those side edges converge, even if only very gradually.

Of course the odd cylinder having parallel edges isn't a big deal - but the fact that this issue is present throughout the entire section does suggest that the manner in which you are approaching the instructions may need to be altered. Be sure to consider why this occurred, and how you can change your approach to avoid it in the future. My recommendations would be to consider taking notes to summarize the important points of what you read/watch, so that you can go through them more regularly whenever sitting down to do the work, as well as periodically doing a fuller review of the instructions to ensure nothing was left out of those notes.

Continuing onto your cylinders in boxes, overall your work here is considerably better, although there are a couple things I want to point out that'll help you get the most out of this exercise going forward. 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.

The two main issues right now are as follows:

• There are quite a few points where you're not drawing your ellipses such that they touch all 4 edges of the plane enclosing them. Remember - the ellipse itself is an error-checking tool. The goal is not to draw the right ellipse, but rather to draw the ellipse that fits in order to assess whether the plane's proportions were correct or not. Ensuring that the ellipse fits the plane is therefore quite important.

• Keep an eye out for cases where the proportions of your plane are really far off, like this one. In cases like this, it can seem like the ellipse isn't that far off, especially if we don't pay enough attention to where the minor axis line actually is on a given ellipse, and where it's supposed to be. In that example, for the ellipse closest to the viewer the minor axis line is way off, as shown here, but it looks like that went unnoticed. When things end up that far off, it's easy for our brains to convince us that it's actually correct, so paying close attention is very important.

Unfortunately while the second section does get a pass, I will need you to complete the 150 cylinders around arbitrary minor axes again, being sure to adhere to the instructions as closely as possible.