Partial 250 Cylinder Challenge submission

1:34 PM, Saturday September 4th 2021

First take on the 250 cylinders challenge - Album on Imgur


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I'm struggling with this challenge! As you can see my cylinder have a bad shape.

Could someone explain how we check if the cylinder is correct? Do we put the ruler along the axis a draw

a line? Do we use the ruler to measure and check if axis is correctly in the middle?

I also have problems to vary the degree of the ellipse. Is there any warm-up/ preparation exercice that could help me?

As always thanks in advance for the help!

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5:01 PM, Wednesday September 8th 2021


To answer your questions first:

Could someone explain how we check if the cylinder is correct? Do we put the ruler along the axis a draw a line?

To check if a cylinder is correct, you need to check whether the "true" minor axis of the two ellipses at each end match with the original minor axis defined for the cylinder, the line that you drew in the beginning. To find the true minor axis of an ellipse, you need to find the line that goes through the center of the ellipse along the shortest path. Another way to think about it is, there are two lines that divide an ellipse into two equal halves, such that when you fold one half over the other, they completely overlap. These are the minor and major axis lines of the ellipse. The minor axis is the shorter of the two. Since there are two ellipses, there are two minor axis lines that you need to make for each cylinder.

I've also found that finding the halfway point between the two lines representing the side of the cylinder helps in determining the center of the ellipse, and therefore roughly where the minor axis is. This is not 100% reliable, so good judgment is still required to figure out the minor axis.

The minor axis that you have drawn for the cylinder should not factor into this at all.

Checking your work, it seems like for the most part you are getting the true minor axis correct. There are a few that seem significantly out of place, like 6 and 17, make sure that the line is going through the center.

Do we use the ruler to measure and check if axis is correctly in the middle?

You can if you want, and it works for the most part, but unfortunately unless your ellipses are perfect there is no guarantee that the minor axis lies in the middle between the two sides of the cylinder.

I also have problems to vary the degree of the ellipse. Is there any warm-up/ preparation exercice that could help me?

The funnels exercise is by far the best warm-up for this. You practice both aligning ellipses to a minor axis as well as varying the size and degree of the ellipse, both of which are important to drawing cylinders in perspective.

I also wanted to give some advice for this challenge in general:

  • So the prerequisite for this challenge is the completion of lesson 2. I've noticed that you have not completed lesson 2 yet, as the TA critiquing has assigned you some revisions. You will need to finish those first before you can work on this challenge. In addition, the recommendation for this challenge is the completion of lesson 5 (constructing animals). Although lessons 3 - 5 do not specifically deal with ellipses, practicing them in those lessons and the warmups will help when making the ellipses for this challenge.

  • There are some issues with the linework here. You do not draw through all of your ellipses (remember you need to draw through every single one) and your straight lines are kind of wobbly, and inaccurate. Inaccurate straight lines are normal to start out with, but by the point of this challenge you should have enough practice to make them more accurate. Your ellipses are not very even, perhaps due to not drawing through them. Make sure you are practicing lines and ellipses in your warmups.

  • The closer end of a cylinder is larger, due to perspective, and has less degree, as seen here. In several of these cylinders, the larger side has larger degree. This breaks the rules of perspective.

  • You are drawing the sides of your cylinders very long and the sides very small. The smaller ellipses make it more difficult to construct proper ellipses. Instead, you want the ends of your cylinder to be big and the sides to be about medium length (though it is good to vary the length of your cylinders).

  • You are varying foreshortening somewhat, but it is generally pretty shallow foreshortening. You should try more dramatic foreshortening as well. Remember that you are required to vary the amount of foreshortening throughout the set.

To summarize, you will need to first finish your lesson 2 revisions before starting this challenge. I do recommend also finishing lessons 3 - 5 first, though that is not required. You will also need to work on linework in your warmups, and may want to review how perspective applies to cylinders.

Hope this helps.

7:53 AM, Thursday September 9th 2021

So the 250 cylinder challenge is not before lesson 5 huh? I started to give a try because I wanted to change from the texture analysis, which is really challenging for me (and also a lot of other peoples I think...)

I'll keep the challenge in pause for the moment to came focus on the main issues I have with Lesson 2

even if it is very unpleasant and frustrating on the moment...

As you can see in the link my texture analysis is very shitty. The TA said that I should focus on not trying to draw from memory and focus on the references. I've included my pictures used as referenced in the link. Could you please tell me if you think those images are good references ?

To try to understand better the exercice I've download texture analysis from other students. I've noticed that some of them where using shadows in the first column.. but it was nonetheless different with the third column. In the third column we need to combine cast shawdows with the spare -> density scale is that correct?

Thanks again for your answer. Any advice for the texture analysis is more than welcome...

2:07 PM, Thursday September 9th 2021

So the fish scale and rock textures are a bit small, I would recommend getting pictures more the size of the wood texture. But they're workable.

The first thing that I noticed is that you do seem to be working a lot from memory. The left square is supposed to be an exact recreation of the shadows in a part of the reference. But there are signs that you did not recreate the reference in all 3 rows: the small triangular shapes I see in your wood analysis are not in the reference, the rocks are all different sizes instead of being roughly the same size, and the scales are facing the wrong direction. The line on each of the fish scales I also do not see on the reference.

You need to draw what you see, not what you think you saw, or what you think wood, rocks or fish scales look like. That's the difference between drawing from observation and memory. This involves looking at the reference every time you want to capture something, then putting it down, then looking at it again, resulting in about 90% of the time looking at the reference and 10% of the time actually drawing.

As for cast shadows, you should only be capturing the cast shadows you see in the panel on the left. Right now, you are still drawing explicit form outlines. The way to think about cast shadows is to see what forms are present, then think about how they would cast shadows on their surroundings. In references like the rocks, this is easier, you can draw the cast shadows (dark areas) that you see directly, in others you will have to think about where those cast shadows will be. But at this point, getting this perfect is not a big deal, there's going to be a lot of form and texture practice required. Just make a goal to capture cast shadows.

In the third column, you try to manipulate the density of cast shadows to create a gradient. The best way to approach this is to start in the middle with drawing cast shadows just like you captured on the left. Then, moving to the left, make each of the cast shadows you draw bigger, join them together, ultimately making them solid black like the black left bar. Towards the right, shrink the cast shadows until there are no cast shadows left. Think about a hierarchy of cast shadows here, the deepest shadows will be where multiple forms intersect, while the lightest area will be on the surface of the forms. The deepest shadows will be the last ones to be removed when shrinking shadows, the lightest areas will be the last to be filled with black when growing shadows.

Hope this helps.

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