Measure Depth! Keep Track of Imaginary Space
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Measure Depth! Keep Track of Imaginary Space
courseThe Perspective CourseSelected 2 parts (138 lessons)
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Charlie Nicholson
We're pushing the deadline for this assignment from August 30th to September 13th, the Sunday after Labor Day! That's an extra two weeks.
LESSON NOTES

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This lesson stretches your brain into space and gets it exact. You will learn how to measure away or toward the viewer. We will start with the simplest trick to divide things in half in perspective.

X Finds the Center

Drawing an X from corner to corner of a rectangular plane finds the exact center. This cuts the plane perfectly in half.

The angle of your tapering lines changes the position of that central point. A highly foreshortened rectangle with a close camera pushes that halfway division far back. You get some leeway for how much you taper the edges and how far back you place the center.

You can use this to find halfway points on the floor, the walls, and the ceiling. You can do it again to divide the space into fourths. You can keep dividing from fourths into eighths.

Notice that when there is already a halfway line on one axis, you do not need a full X. Just one diagonal will find the center of that rectangle to create the halfway line on the other axis.

A grid of halves stays in place when you put it in space. This works in any kind of perspective. It works close up or far away. It works in 1, 2, or 3-point perspective on any rectangular plane. It is simple, fast, and precise.

The Limit of X Finds the Center This method only gives even divisions. It cuts things in twos, halves, and their halves.

Diagonal Transfers

If you want odd divisions like thirds, fifths, or sevenths, you need a different approach. We call this the checkerboard method. It uses a diagonal line to transfer divisions. The advantage over finding the center with an X is that this works for both even and odd divisions.

Here is how to divide equal segments on a foreshortened plane:

  • Find a line that is not foreshortened, like the front edge of your plane.
  • Divide this unforeshortened line into your desired equal parts.
  • Run those dividing points back to the vanishing point to create converging lines.
  • Run a diagonal line from corner to corner of the plane.

Every point where the diagonal touches the converging lines transfers those divisions into perspective. It perfectly calculates how much smaller to make each partition as it goes back in space.

Dividing the Front Line

Dividing a straight line is easy for halves. Dividing an odd number is not always that simple.

Measuring the distance in millimeters and dividing it by your chosen odd number is slow. The fast way is to find a stretch on your ruler that nicely divides with your chosen number. Angle the ruler until that divisible length fits between your boundaries. Mark your divisions and use those points.

Transferring Uneven Divisions

The segments do not have to be all the same length. You can have a short one, a long one, and a medium one. They will all transfer front to back from one line in draft view to one in perspective.

When the sections recede in a particular order, place them on the non-foreshortened line in the order you want them to go away. Start your diagonal in that particular corner to send them front to back.

The Guiding Principle Get anything out of perspective, divide it, and transfer the divisions with a diagonal line. This takes care of the whole room.

These methods work on a floor, a ceiling, or a wall. They just require a back boundary to work.

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ASSIGNMENTS
Bryan Krauss
Here's my submission for critique. I had a great time putting into practice the concept Marshall laid out in the videos. This first set was done soon after the release of this video and I didn't have all the tools Marshall has since laid out. I was guessing at how to do the spacing of the floor boards on the front deck. They turned out fairly well but not quite accurate without using the special VP. I'm still not quite sure of the workflow when using tracing paper. Is it merely for transferring to another page? This seems a slow exercise in transferring the drawing but is this the only way?
Bryan Krauss
Here's my second attempt using the remainder of the tools, like the special VP. It's quite the puzzle to figure out the best way to figure out spacing and running lines this way and that way. This time I just used the tracing paper to trace over the bones of the drawing into something loose and fun (at least loose for me!).
Stepka
3h
My ideal studio has three levels and so will need a staircase.
Stepka
7h
Figuring out how to divide length in regular intervals using diagonals. If we already have divisions into smaller number of intervals, we can use those divisions to construct divisions into smaller intervals. This may not be the most efficient way to divide a line for perspective work, but I uncovered some nice mathematical structure beneath. I got curious, followed it further than strictly necessary, and had fun.
Stepka
7h
Studying stairs in all possible angles, finding it instructive.
Pamela D
12h
Hi Marshal here is my part two of the studio with Diagonal Vanishing Points for the floor pattern and using the diagonals for equal divisions on the wall mouldings.
Mon Barker
14h
On the design question, these techniques definitely force you to pause and think ahead….sometimes I thought to get rid of eg the wood cladding where the details get so fine that any measurement/ruler imperfections mess it up completely. So I can understand the Windsor Mackay ‘arches’ example Marshall showed way back….good enough, not measurement perfect! I see that rigid measuring loses the gesture and you end up with a structurally perfect but slightly soulless technical drawing, but appreciate the need to practice this extensively so the concepts sink in and you can wing it with style later. Had some back and forth with @julespeppler on how you would apply the techniques in curvilinear/5 point perspective. Conclusion - it’s possible, you make a system that you know is inaccurate, understand how broadly things should look then stick with it …it kinda works. However, only for the bigger structures. It totally breaks down with finer repetitive details as the inaccuracies quickly mess things up. Again, with experience and understanding of the concepts, I guess you intuitively and stylishly fill in those details. Maybe there is a better way that does not involve calculating the geometric moment of every arc….?
Jules Peppler
Mon, this turned out so well. Looks like you have a knack for designing boats too! The finished piece is so satisfying to look at. Wish I could go there myself and explore that building. Looks like your measuring under fisheye view is working out well too!
Neill
13h
Really cool and quirky design Mon. great use of inclined planes to make it angular and interesting, I see those box flaps! :) One question that has been bothering me. Do you think you can apply a measuring line to the box flap for equal divisions in perspective? if so, where does the measuring point wonder off to? not the horizon, surely?
Li Ming Lin
This is a little deck extension. It was cool to see how the wooden planks on the left viewpoint got dramatically thinner as they got farther away, compared to the planks on the right viewpoint. Also after having a second look, the food bowl on the left viewpoint could be bigger... Otherwise, I was happy that I got to use a vertical trace, along with the 'X centre' method and the diagonal transfer. Super useful!
Norm Lanting
Marshall. I’m sorry I didn’t submit my dream a few months back. At the time I tried to convert a lamp stand into a huge building. It was made up of circles and curves and I thought I could use squares and cubes to construct it, but I bit off more than I could chew. When I realized I was out of my depth, I figured I’d do the perspective with a cityscape or scene requiring perspective with my monumental dream studio in the background. But I ran out of time. I included some images of my planning for the original dream studio assignment and some sketches which were in the line of Robert Montald (I was taking his sketching course at the same time). The image for this assignment is a cityscape inspired by a recent trip to Europe. My dream studio looms over the city in the background. I also included an image showing the perspective planning.
Mon Barker
14h
Amazing work Norm!
Lin
1d
Hi Marshall, please don’t laugh at this, I know it’s incredibly unfinished and incredibly wrong but it was all I could do for this one. The difficulty is there are layers and layers of walls, floor levels and things sitting in front or behind each other which repeat and which I’ve not yet worked out concisely since this is just the intuitive sketching stage that’s NOT meant to see the light of day. I don’t yet know how it should look behind the statues and I know I need to add wall thickness to stuff like the alcoves, all which require me to zigzag along the floor plan. The tilted camera and view from above doesn’t help but I like this kind of thing so I thought I’d try. Anyway, the reason I chose this is 1) I want my studio to be an ancient temple because why not 😆 but also because the measurements we are learning now are hopefully going to help me space out all this stuff correctly. The statues, alcoves, doors, and even the patterns on the carpet which have spaces between them which repeat vis a vis each other. The fire lamps I will use diagonals for eg to space out when more time and augh why did I choose this WHY Anyway…sorry 😬
Mon Barker
14h
Looks great Lin 🙌
Jules Peppler
Looks like you are ready to start a job in visual development. Awesome lighting scheme and perspective!
Neill
1d
I did different bits of my dream studio as I had laid it our across several floors and rooms. As each new lesson came out it would effect the technique I'd use to set up the picture. In the kitchen one I got kind of obsessed with doing a floor tile pattern, so much so I forgot to add the furniture. at points it looked like an optical illusion and I had to do it more then once. Also As I was pulling out the page I tore it in half... eh... hence the sticky tape. I did have a slight problem on figuring out where to place the measuring point if I wanted to use it on a line that was basically parallel to an axis or followed a vanishing trace, it would sometimes give me some crazy divisions. having said that, when you get it right, wow the time files. :) I hope the spaces that I did manage to flesh out feel as relaxing and cosy as I intended. Also my first post that has been in time for a deadline! Whoohooo! :P
Mon Barker
14h
Great result. Love the building design
Neill
1d
Also some Experiments I did to figure out what I liked and what confused me. :)
Dermot
1d
Where did I go wrong? Why is the left side centre line not converging to the right VP? The line is passing through the left side "X" es but not arriving at the VP. See the drawing I worked along with the video. Any advise would be great. :)
Sita Rabeling
When I put my ruler on the screen through the X's the line ends on the VP, so nothing wrong here in my opinion...
Jules Peppler
It was awesome to have a little extra time to work on these. Thank you! I would say I'm most proud of the ladder 🪜 It felt like I was building one in real space. I made use of the vertical trace to tilt it and diagonal vanishing points to keep proportion consistent. I took a crack at building stairs on an exterior view as well as a fisheye view interior. A bit wonky, but, the journey was well worth the effort. 🧠 I think the size of pen I was using threw off some of my measurements where the line was thicker or thinner. Will have to be more conscious of that in the future. As always, having way to much fun!
Neill
13h
Awesome stuff, thanks for sharing the line work on your stairs and decks, I bet the view from that studio is stunning :)
Mon Barker
14h
Love the cliff top retreat idea and stairs leading up. Nice work Jules 🙌
@lwel
2d
I did not learn that folding trick at kindergarten and now I'm filing a complaint
Patrick Bosworth
Smithies
2d
Definitely a work in progress - 1st pic is what I’m working on at the moment, based on floor plan from second pic. Added 3rd pic as that’s where it started but there have been big changes! Still might think about adding a tower room later, not going to to lie, I do fancy a turret… I’m adding it now because I didn’t want to post it in the first dream studio assignment because I was embarrassed because it looked so bad, but now it can just be step one and that’s less bad. I’m seeing things I’ve done that look wrong. I should have started with a grid, but actually I popped that in in the middle and it should have been there from the start and I’m not convinced I popped it in right so sometimes I’m working from lines I probably shouldn’t be working from…. anyway, I’ve done the best set of stairs I’ve ever done in my life, so bit happy with that, even though I’m realising that the line at the bottom of each stair should probably be curved. Whooops. The cupboard on the left definitely looks wonky. Don’t get me started on my loo and sink. And they’re hard even as boxes! Let alone when I try and curve them, which I will do at some point. And I haven’t even mentioned the underfloor fish pond… But I couldn’t have done this before the course, so there’s progress - Thanks Marshall!
@rupertdddd
I decided to simplify the building and just concentrate on the external stairs for now. Once I did the plan and elevation drawings I placed the plan onto a square. I did not know how to draw a perfect square on the ground so I used the Zolly app to make the square and worked on top of that. My intention was to do a closeup of the lion but it became way too complicated with lines going all over the place and I gave up… for now the lion stays a hand drawn sketch…🤯
Jules Peppler
Thanks for sharing your whole process. There are some things here I didn’t think of trying. Great work planning everything out! The overall effect is excellent.
Patrick Bosworth
Oh, yeaaaaaaah! Excellent work!!
Dooby
3d
I apologize for the messy-ness, I did a lot of different things on the same layer. Organization is something I gotta work on hehe. But anyways, I took this as an opportunity to fix those ceiling windows from the last critique. I'm still not 100% sure if I correctly copy and pasted the curve of the window down the Z axis, if that makes any sense... As tedious as some of this was, it's very satisfying to have so much control over the perspective of a drawing X)
Ariadne
4d
The only Way to keep track of all
sara keyes
Pamela D
13d
Hi, here is my submission starting with my original dream studio. The grid that I built is based on 3ft per square. I used it for the floor plan to map the building shape, the height (Y line on corner furthest away) and the VP's for the elevation. The diagonal walls are elevated from the floor plot using the square diagonals. I actually used another penciled grid with vanishing points further away, and included the first grid in red as it shows the divisions of the squares dropping down to make the perspective grid.
Sita Rabeling
Looks great! Nice touch with the Penrose triangle :)
Charlie Nicholson
We're pushing the deadline for this assignment from August 30th to September 13th, the Sunday after Labor Day! That's an extra two weeks.
Stevie Roder
Thanks ever so much on this Lin. I so wanna get moving forward with my dream studio sketches I did back in ye early phase of our concepts big time. This makes me happy to see we've been given extended time for it.
Lin
16d
thank you so much 😭
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