11:28 PM, Wednesday August 24th 2022
Starting with your cylinders around arbitrary minor axes, one thing that stood out to me quite quickly was just how many of these cylinders appear to be drawn without any convergence - as though their vanishing points were being forced to infinity. It's very fortunate that this was not the case for all of your cylinders for this section, but it's the case for enough that it is definitely something we're going to have to address.
The reason this is a problem is because it is incorrect. We do not actually control where our vanishing points go - not directly, anyway. What we control is the orientation we intend for each form we draw, and it is that orientation in relation to the direction the viewer is looking out onto the scene that determines where the vanishing point will fall. When the vanishing point governing a set of edges goes to infinity, it's specifically because those edges it governs are running perpendicularly to the viewer's angle of sight - in other words, those edges are not slanting towards or away from the viewer through the depth of the scene.
Given that we're dealing with a bunch of randomly rotated forms here, like in the 250 box challenge, we can say that the chances of achieving such a perfect alignment once in 150 is unlikely, and we may as well just ensure that we're always having our edges here converging towards a concrete vanishing point.
Continuing onto the cylinders in boxes, I can happily confirm that you do appear to have applied the mine extensions here correctly. And that's good, because they're extremely important as far as the exercise goes. 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 only thing I would recommend here is that you appear to be extending your minor axis in a fairly limited fashion, similarly to the previous section. This one however would benefit more from having those minor axes - both of them - extended all the way back with the other lines that are meant to converge towards the same vanishing point. The process after all relies on judging how all of these lines within the same set are converging, so if some are left further behind, we are diminished in our ability to judge those convergences.
Now, I am going to ask for some revisions, but as you did not force all the vanishing points to infinity for that first section, the revisions will be significantly less of what they would otherwise have been.
Next Steps:
Please submit an additional 50 cylinders around arbitrary minor axes. Be sure to dramatically vary your foreshortening here, but do not draw anything with a vanishing point forced to infinity.