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nancymae
06-15-2004, 01:42 PM
Hello fellow pastelists: I am having a terrible time with perspective issues. I have posted a thread over in the plein air forum regarding this issue. My problems come from both sketching on site, as well as from photos. I have studied perspective books...and still don't "get it". I also use an angle finder when I am sketching outside...my buildings all look like they are tipping over.

What do YOU use for perspective? Or do I need to go back to those books?

Thank you in advance!

Nancy

Khadres
06-15-2004, 04:50 PM
Well, to be honest....the way I deal with perspective issues is to steer clear of 'em by not painting buildings, etc.! :rolleyes: You might ask Jackie Simmonds...she seems to have a good handle on that kinds stuff and knows how to explain things very well.

I don't think it's all that difficult once you see it demonstrated, maybe on something of your own...might post something you're not happy with and let those in the know draw over it in a graphics program so you can see.

Then.....when you have it down pat....you can 'splain it to ME! :D

DGrau
06-15-2004, 05:25 PM
Perspective is based off of a horizon line, the horizon line is at whatever height your eyes are looking at, and a vanishing point is where the projected lines of the apparent angles of the building from above and below the horizon line meet.
When veiwing a building, only seeing one side of it on an angle, you have one point perspective.
Everything below the horizon line will angle upwards to the vanishing point and everything above the horizon line will angle downwards to the vanishing point. JUst find the angles which match best what you see.
When see two sides of a building, two point perspectve comes into play. You simply have two vanishing points now, one for the left side and one for the right side of the building, both points lying on the horizon line.
Especially when dealing with very tall buildings (skyscrapers) 3 point perspective can come into play. You will have your two point perspective and also a third perspective from above. This will cause the sides of your building to appear to be not straight, but to taper inwards as the apparent angles recede to the vanishing point directly above where you are veiwing. Unless the building is extremly tall it is usually best to just draw the sides of your building straight up and down.
Just remember each brick, roof line, window, etc, diminishes in size and follows the line towards the vanishing point.
David
Fences, telephone poles, anything of equal size follows this rule.

jade fox
06-15-2004, 05:34 PM
Good timing for this question, I just photographed an old stone church I might attempt to sketch tonight. The height of it makes for a huge perspective issue. :cool:

nancymae
06-15-2004, 05:40 PM
Thank you sooo much for your explanation David...it is perfect! I never understood why you needed one point versus two point or more perspective. One silly question...when looking at a photo, how do you know where the horizon line is?

Nancy

DGrau
06-15-2004, 05:53 PM
no questions are silly nancy....
I came back to edit but wil answer here..the horizon line is at eye level not where you are looking I belive. you would have to look at the photo and determine where eye level would be.
I recalled a thread containing diagrams and an in depth talk about perspective,,found it but do not know how to link.... look up wc member henrik and look at his posts....go to page 5 and click on humans perpectives and empty spaces..3 pages of the thread..lots of info..let me know if I can be of further help
Best
David
Edited to correct members name

CarlyHardy
06-15-2004, 07:48 PM
Nancy,
Here's a really good demonstration showing line by line how to draw a building in perspective. You could easily work along with the images, too!

http://www.wetcanvas.com/ArtSchool/Drawing/RenBarn/barn01.html

For several other simple to follow demonstrations, check out the Articles in the Drawing and Sketching Forum Channel :) There's a lot of great things there about perspective. (I love having pictures :))
carly

jackiesimmonds
06-16-2004, 05:23 AM
Nancy, could you be specific about what it is you do not understand about perspective? I looked at your website, and seems to me that you do understand quite a bit.

As for your buildings looking like they are falling over, if your verticals aren't vertical, then they will. Simple as that. Your pic of a window is a good case in point; look at the edge of your mat, and the leftmost vertical - you can clearly see that your vertical - isn't vertical!!

The best way to "use" perspective, is as a tool to check your drawing. So - the procedure when drawing or painting should be:

1. Draw freehand, measuring as you go (that business of holding out your brush or pencil, to check heights against widths. Let me know if you aren't sure about this, anyone). Start with the biggest shapes - the overall shape of a building, for instance, before worrying about doors, windows, etc.
http://www.wetcanvas.com/Community/images/16-Jun-2004/1805-measuring.jpg

2. Mark in your horizon line. To find this, put your closed sketchbook on the bridge of your nose and look out across it. THAT is your horizon line. (in a photo, put your photo down onto a larger, blank sheet of paper. Extend angles from roofs, and bases, to find a common VP. That will be on your horizon.http://www.wetcanvas.com/Community/images/16-Jun-2004/1805-2pt_perspectivephoto.jpg)

CHECKING

3. NOW you can use perspective rules to check your drawing. Use a dotted line to extend one of the angles ... let's say the roof line ... down to the horizon. That gives you your vanishing point, where the dotted line hits the horizon line.

4. Now a second angle - say the base line of the building. See if that line meets at the vanishing point too.

5. Check your verticals. If you aren't sure abut them, use an L-shape piece of card. Line one edge with the top of your paper; the other part of the L will then be a perfect right-angle, and will give you your verticals. Again, let me know if this is unclear, I will provide a drawing.

6. If your vanishing point is off the paper - it often is - then lay your paper onto a BIGGER sheet of paper. Extend the horizon line onto the bigger sheet. Then find your VP on the horizon line.

Once you are happy with the main angles, all the other angles will slot easily into place - tops of doors, windows, bricks, etc, should all follow the rules of meeting at the VP.

BASICS:

With 1 point perspective ... just one side of a building, or a wall, or an object directly in front of you ... you only have one vanishing point.
http://www.wetcanvas.com/Community/images/16-Jun-2004/1805-1pt_perspective.jpg

With 2-point perspective, you will have a left face, and a right face, to the building or object, it will be "corner-on" to you. So you will have 2 vp's - one to the left, one to the right.

http://www.wetcanvas.com/Community/images/16-Jun-2004/1805-2pt_perspective.jpg

With a very tall building, you also have a VP above you - the sides of the building may slope in very gradually as your eye moves up the building. This is called 3-point perspective, and it happens when we look up at very tall buildings from a point close to the base, or if we look down on a structure from above.
http://www.wetcanvas.com/Community/images/16-Jun-2004/1805-3pt_perspective.jpg

In both 2-point, and 3-point perspective, the vanishing points should not be arbitrarily placed too close together, this will cause huge distortions.

I think you DO know all of this, actually, so let me know what it is you feel you aren't doing.

J

ps all of these examples are from a small, simple section on perspective in my book PASTELS WORKSHOP.

nancymae
06-16-2004, 10:12 AM
I FINALLY UNDERSTAND THIS STUFF!! Thank you soooo much David, Carly and Jackie!!! I did not "get" why you have the different perspectives...one point versus two or three.....duh...how many sides of the house can you see!! I never understood that in any of my materials!! I am printing all these out and studying them...now I want to go to Washington DC and tackle all these buildings I saw on tv last week!!

I fixed a building last night that I was working on...no more crooked windows...or leaning spires!! Will post when I am done!!

THANK YOU THANK YOU THANK YOU THANK YOU!! I have grown sooo much as an artist just by reading the posts here on WetCanvas!!

:clap: :clap: :clap: :clap: :clap: :clap: :clap:

Nancymae...who is no longer tilted!!!

jackiesimmonds
06-16-2004, 02:18 PM
Nancy,
Here's a really good demonstration showing line by line how to draw a building in perspective. You could easily work along with the images, too!

http://www.wetcanvas.com/ArtSchool/Drawing/RenBarn/barn01.html


carly

Carly - I would like to take issue with over this. Yes,these are fascinating photos, but I am afraid that they only go part way to explaining the whole business of 2 point perspective. There is A HUGE OMMISSION in the process, and that is, getting the proportions right in the first instance.

anyone reading thro carefully, and following along, will certainly be able to create THIS barn. But it will not help them when it comes to tackling any other building, and one with different proportions.

This is something that I stand up and yell about as often as possible. DO NOT USE PERSPECTIVE RULES ON THEIR OWN - YOU MUST MUST MUST START WITH MEASURING THE PROPORTIONS OF THE BUILDING, OR SHAPE, OR WALL, OR WHATEVER IT IS YOU WANT TO DRAW.

So many authors, and teachers, forget to tell their pupils this, it is almost as tho it is "a given" in their minds, and it should not be, and this set of photos is a classic example of teaching which starts from the wrong place. THE ESSENCE OF GOOD DRAUGHTMANSHIP IS GETTING PROPORTIONS RIGHT, and this must be done before you use perspective rules to check your drawing.

The placement of the barn door is a classic example. Why did the author make it that size? Because it was? Or because he felt like it? tHERE IS NO MENTION OF MEASURING, and there should be. And why didn't he show us how to find the perspective centre of that side plane?

Once you find the perspective centre, you have something to check the main placement of the doorway, and THEN you have to measure that doorway, in relation to the remaining shape of that side plane.

Please, everyone who looks at those photos, remember that the calculations given ONLY RELATE TO THAT PARTICULAR BARN and not to every barn, or building.

nancymae
06-17-2004, 10:10 AM
Jackie...the point you make is EXACTLY the confusion that I have felt in learning perspective. Most always, I just try and "fake it" by either putting bushes in front of my bad angles, or just avoiding buildings and structures all together. You and David's explanation made soo much sense to me. I believe that many books and articles on perspective DO take the subject from the sense you talk about..how to draw THAT particular barn. I want to know WHY that guy was doing what he was doing...how did he come up with the placement on the page..etc. etc. Your and David's explanation hit it right on the head!! I'm going to go out and try my hand at some buildings with my new knowledge now!! I will post the before and after paintings!!

Thanks again everyone!!

Nancy

jackiesimmonds
06-17-2004, 10:30 AM
I'm going to go out and try my hand at some buildings with my new knowledge now!! I will post the before and after paintings!!

Thanks again everyone!!

Nancy

Nancy - as for placement on the page...the best thing to do, when out on location, is a little thumbnail sketch, which will help you to decide exactly how to place your building, in relation to the edges of the rectangle. If you work in a sketchbook, create some rectangles BEFORE you go out. (and a viewfinder) Make sure there is plenty of white space around your rectangles, so that you can make the rectangle a bit bigger, if you feel the image needs it. Do not work edge to edge of the page, that limits you.

Then, you will have no problem at all, placing your building on your pastel paper. Just refer to your thumbnail sketch, and see the placement there, and work accordingly! Simple!
Then, all you have to worry about is getting the perspective angles right :evil:
Jackie

Khadres
06-17-2004, 11:26 AM
This is going to sound really silly, but I read through that article too and, while it was neat and very exact in measurements and so forth, I couldn't help scratching my head and thinking....surely not EVERYTHING has these so-many-inches and fractions measurements in it! So what good is all this "1/4 inch" here and "two inches" there business??? I think I wound up more confused than when I started on that one! THANKS, Jackie, for explaining the fallacy there...the author never once mentioned WHERE his measurements were coming from...and that's the most crucial part!

Also, am I wrong in thinking that especially if you're out on location, etc. you're going to have to use more of a, as you say, "proportional" style of measurement anyway....ie: The roof is roughly a quarter of the width of the rectangle of the paper and the door is a third of the height of the roof, etc. rather than arbitrary ruler measurements. I'm not too good at using a pencil or whatever as a measure, but I do see how that works and just need to practice it more.

Where I get REALLY messed up is when there are multiple vanishing points...it looks so simple on paper when someone demonstrates it but, boy, it can get really confusing in a hurry! I guess one just has to attend to each different object one at a time AND IN RELATION to the other objects within the scene. Whew! Would LOVE a step by step of just how to do THAT, too!

SweetBabyJ
06-17-2004, 12:47 PM
The author of that article is a draftsman, Sooz- an architect- so it's like when a computer geek explains something in Windows to a novice: He already KNOWS what the building measures in his line of sight, and has done the math in his head beforehand. He just assumes you know, too. It's such a basic piece TO HIM, he doesn't realize others may not understand. But that's why those measurements come into play- he is being *exact*, rather than judging by proportions. The mathematical ratios, though, if you took the time to figure them out, would be the same for any building AT THAT ANGLE.

Thankfully, I dumped all ratios once they came out with nursing calculators and I'd passed ChemII.

jackiesimmonds
06-17-2004, 01:05 PM
Sooz, you don't sound silly AT ALL, you are absolutely right about those measurements in that series of photos, they only refer to THAT drawing and THAT barn, and are not helpful when it comes to working out on location, and sorting out the scene in front of you.

Yes, use your eye ("that doorway seems to be about half the height of that wall."...etc) and draw freehand. But DO practice measuring , it is really easy, and you need to master it, since with bad proportions in a picture, it will always look amateurish. You say you know about it, but need to practice. Perhaps it hasn't been explained properly to you, because I am sure that if you knew how easy it was, you would be doing it all the time. I certainly do. Why not practice at home. Do it with a door in your house.

1. Grab a long pencil, or paintbrush or garden stick.

2. Hold it out with your elbow LOCKED, this is important,

3. close one eye when you look at your door, and line your pencil up with one side of the door, with your thumb further down the pencil, lining up visually with the right hand corner of the door. Like this:

http://www.wetcanvas.com/Community/images/17-Jun-2004/1805-with_stick.jpg


Then, keeping your thumb firmly in place, TURN YOUR ARM AROUND WITHOUT UNLOCKING YOUR ELBOW, so that the pencil is now pointing at the ceiling. Then, ... see how many times that width"goes" into the height, using the fixed width measurement you have found, and dropping it down the door.

Then try a window. Keep measuring stuff, and gradually it will become second nature. If you want a more detailed set of drawings, showing how to do it, let me know.

On location, begin with a simple thumbnail. In it, establish your eye level.

Then, decide whether you are dealing with more than one vanishing point...if you can see the corner of a building, there will be more than one. The point is, once you have your eye level, then YOU KNOW that all your angles must converge at a vanishing point on the eye level ...whether it is the vp to the left, or the vp to the right.

If there are objects at funny angles all over the place ....for example, a field full of blocks of hay, all at different angles to you, they will all have different vp's, but all on the same eye level.

Is this clear? Wish I could come out drawing with you, to help.

J

judwal
06-17-2004, 01:45 PM
I took this photo while in Boston last sunday. I am considering doing a pastel of this..but look at all the perspective! Do I dare?

SweetBabyJ
06-17-2004, 02:06 PM
Yes.

If you don't, then can I give it a go sometime?

judwal
06-17-2004, 02:52 PM
Yes.

If you don't, then can I give it a go sometime?
Sure...be my guest! I'm still not sure if I want to tackle it anyway.

I was trying to upload these into the image library anyway. Since it's not working for me I've been unable upload any of my recent photos. I've got some really pretty ones of the pots with flowers too.

DGrau
06-17-2004, 04:02 PM
edited

Khadres
06-17-2004, 04:24 PM
Is this clear? Wish I could come out drawing with you, to help.

Oh, you and me BOTH! Would be a blast to draw or paint with you. You're a treasure trove of tips and common sense ideas for tackling otherwise complicated things! If I didn't know you already had tons of stuff to do right now, I'd ask ya to do a new perspective article, putting it all into artist lingo with illustrations! Makes a big difference...what you're using perspective FOR, I think. Thanks for taking the time to explain all this to us!

And SBJ? You're talking to the gal who cleverly avoided Chem I, much less Chem II, and had to take Algebra I TWICE to pass it! :D This is why your scene (and a good many of Meowmeow's complicated subjects, as well) would've intimidated me from the git-go. I can often spot or "feel" something's wrong with something, but am usually at a loss as to exactly how to fix it.

jackiesimmonds
06-17-2004, 06:13 PM
I took this photo while in Boston last sunday. I am considering doing a pastel of this..but look at all the perspective! Do I dare?

Judy, this would be no problem at all, if you grid it, and then grid your paper and transfer the main shapes. It is SO easy to do this with a photo, it can only be done with a photo or sketch, you cannot do it from life!!!

Only one thing I would say about the photo....the structure is interesting, as are the shapes and angles, but the light is very even and flat, so there is little sense of atmosphere in the picture. Provided you don't mind that ...then why not give it a try.

J

soap
06-18-2004, 04:08 AM
Great thread - good brush up on perspective. Thanks all - Jackie - you are so good in explaining things clearly! thanks

jackiesimmonds
06-18-2004, 04:23 AM
dont know if anyone will see this, since the thread is kinda finished really, but I have had one thought overnight, that I did not include, and it is important.

When measuring with a pencil or stick, some people think that the measurement they find, (my little drawing) has to be transferred to their paper.

This is not so at all, it is just the CORRECT PROPORTIONS that have to be transferred.

So, if a doorway's width goes twice into its height, your drawing of the doorway must do the same, so if your drawing is 1" wide, it must be 2" high. If your drawing is 2" wide, it must be 4" high. It doesn't matter what size you make your drawing..........just remember that the proportions have to be the same as the proportions of the object you are drawing.

I realise this sounds obvious, but I have actually seen people trying to do everything "sight size", keeping their fingers glued to their pencil, transferring THAT size to their page, and this is not necessary at all.
Jackie

Khadres
06-18-2004, 02:07 PM
Good point, Jackie! Lessons can sometimes be taken too literally, I know. I can't remember...has anyone rated this thread? Has so many good tips in it, I think I will...