Starting with your cylinders around arbitrary minor axes, I can see that towards the beginning you were running into some issues (from being hesitant to vary your rate of foreshortening, to even having quite a few where the closer end with the hatching was smaller in overall scale than the farther end - number 1 and 4 being good examples of that mistake, though it's present in others as well). Fortunately, as you progressed through the set, you addressed and rectified these issues, so by the end, your ellipses were confidently executed to achieve even, consistent shapes, your side edges were straight and smooth, and you did a great job of identifying the "true" minor axis line, even picking up on fairly small discrepancies.

Another point I'm pleased to see is the fact that as you progressed through the set and experimented more with your foreshortening, you appear to have demonstrated a pretty solid grasp of how foreshortening itself is manifested in two visible ways on our cylinder drawings - one being the shift in scale, where the closer end would be larger overall and the farther end would be smaller, and the other being the shift in degree where the closer end is narrower, and the farther end is wider. The important piece here that some students miss out on is that these two "shifts" must occur in tandem, as they're both used to convey to the viewer just how much of the cylinder's length exists in the "unseen" dimension of depth. If one shift is more dramatic, but the other is minimal, then we have a contradiction where on one hand we're telling the viewer that the cylinder is longer than what we strictly see on the page, and that the cylinder is about the same length as we see on the page. While the viewer may not entirely understand why, they would be able to identify these cylinders as looking "off". So, it's good to see that you understood this, be it on an instinctual level, or a conscious one.

Stepping back for a moment to those earlier cylinders (before you started varying the foreshortening more at around the 50 mark), I did want to quickly explain why eliminating all foreshortening altogether in any of the cylinders here (which we can see in examples like 38 and 39) is actually incorrect. Students often do this when they try to artificially simplify the exercise itself, trying to "place" the vanishing point at infinity in the manner discussed back in Lesson 1. The problem is that we do not control where the vanishing points go directly. What we control is our intended orientation for the form, and there is only a specific set of orientations of a given set of parallel edges, where the vanishing point that governs them actually goes to infinity.

This requires for the set of edges (in our case, the side edges of the cylinders) to actually run perpendicular to the viewer's angle of sight, rather than slanting through the depth of the scene towards or away from them. Given that our cylinders for this challenge are rotated randomly and arbitrarily however (like in the box challenge), we can pretty much guarantee that they'd never align so perfectly, and thus there would always be some convergence towards a concrete vanishing point, even if only very slight and gradual.

Continuing onto the cylinders in boxes, you've done a pretty solid job here. 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.

From what I can see here, you've applied these line extensions as instructed, and have done a good job of catching errors. Looking at 203, I was concerned that, as I've seen from other students, you may have missed just how wildly off-base the minor axis was (it's a bit weird but sometimes when faced with something being so far off, their brain convinces them that it's actually fine), but when I noticed your little "MA?!" marking, I was very pleased to see that you caught the mistake.

As a whole, I can also see that your sense of proportion here is developing nicely, and that at least to the naked eye, your boxes are definitely appearing much more passable as featuring those two opposite faces which are proportionally square in 3D space.

So! I'll go ahead and mark this challenge as complete. There are a few things for you to keep in mind going forward, but I'm pleased to see the growth and progress you've shown here.