Starting with your cylinders around arbitrary minor axes, overall your work here is coming along quite well. You're demonstrating solid confidence and control in the execution of your ellipses, along with a great deal of patience and fastidiousness in checking the alignment of your ellipses. I'm also pleased with the range of foreshortenings you've included here in the set.

On that note, however, one thing to be careful of is any situation where your side edges get a little too parallel. For example, if we take a look at 74 on this page, those side edges aren't entirely parallel, there is some very very minute convergence to them, but the question comes down to what you intended to do there. If you intended to do some very shallow foreshortening there, with extremely minimal convergence, then that's fine. But if you intended to actually draw them as parallel on the page (as some students do), that would be incorrect. Basically the thing to remember is that the only situation where the side edges would actually run parallel on the page is if the edges they represent in 3D space actually run perpendicular to the viewer's angle of sight, not slanting towards or away from the viewer at all through the depth of the scene. This would put their vanishing point at infinity, resulting in parallel lines on the page.

So, in a sense we can control the orientation we want for our form, but we are not in control of where the vanishing point goes beyond that. Given that in this exercise we're rotating our cylinders quite randomly, we can pretty much assume that perfect of an alignment would not occur, so we should generally be working with concrete vanishing points throughout this exercise - which again, if you were purposely just trying to keep very shallow, gradual convergences, that would be correct.

Continuing onto your cylinders in boxes, I did notice a fair number of cases where some sets of edges were drawn too parallel on the page, but it wasn't a consistent issue across the entire challenge - rather something that was scattered across it. If we look at 233 on this page, the lines going down and to the left are quite parallel, as are 232's down-and-to-the-right. Just something to continue to be aware of.

As a whole though, your work throughout this part of the challenge is quite solid. 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.

I can see your capacity to estimate those proportions developing nicely throughout the set, and while there's still room for further progress, your work is coming along well and you should be plenty well equipped to tackle what Lesson 6 will be sending at you.

So! I'll go ahead and mark this challenge as complete.