[imagino]

Hi,

I'm an Illustrator, Photoshop user. Recently, i got interested in Perspective drawing and i wish to incorporate it my works, but i can't find any good informative resource about it on the net. the site i found are just like some scattered articles & info.

i hope to find a really detailed guide to perspective drawing..best if illustrated with examples.

1. what are some of the cmoon tools you guys use in illustrator/photoshop when doing a perspective drawing? e.g. guides, lines..

2. can anyone recommend any good sources?forums dedicated to it?

3. there is concept of 'cone of vision' which i hope to know more in detail. it writes: 'things outside the cone of vision appear distorted'

4. so does it mean the lines outside the cone doesnt not abide the perspective drawing rules anymore? like towards VP.

5. how do i deliberately distort objects outside cone of vision, is there own set of rules for it?

6. should i draw a cone of vison as a reference when drawing it? if yes, at what size % of my artboard should i draw the circle by?

any other info on perspective drawing would also be appreicated..

Thanks :)

[nafa]

Plenty of good tutorials on the web. Here is one that probably has more than you want:

http://www.tpub.com/content/draftsman/14276/css/14276_263.htm

This is a simpler one:

http://www.olejarz.com/arted/perspective/index.html

[Brake Check]

I am studying perspective also..
These two sites seem to be very good..

http://www.handprint.com/HP/WCL/perspect1.html

http://www.khulsey.com/perspective_basics.html

[imagino]

Hi guys,

Thank you for the replies & links! :D

i read through the sites, but i can't seem to find any answer to the following 'cone of vision' questions :

1. i read before objects outside the 'Cone-Of-Vision' starts to distort? what do you mean by that?

2. if it means deviating from the normal perspective drawing rules, does objects outside the cone come with its own rules of distortion? if yes, what are they?

3. say i want to setup my scene, how do i setup the size & location of the cone of vision initially before i start drawing the objects? is there like a relative % size for radius of the cone?

Hope someone can answer.. thanks

[Gort]

Scott Robertson's first volume on perspective basics from the Gnomon Workshop is highly recommended.
_________________
- Tom Carter

"You can't stop the waves but you can learn to surf" - Jack Kornfield

[Mikko K]

I don't really know about your cone of vision thing, but maybe it refers to the fact that objects actually get smaller in distance to ALL DIRECTIONS, not just a couple of vanishing points. This "ball" perspective means that things do really distort somewhat outside the center of your view.. But perspective is generally drawn as linear, because it looks convincing without the distortions and is more simple to understand.

Use a 3D app to create a perspective grid or block models. Helps you out a lot more than any 2d tool.

[Brake Check]

The web page I posted
INTRO PAGE
http://www.handprint.com/HP/WCL/perspect1.html
And this exhaustive explanation from the 1st page explains the circle of vision, the distortion and the corrections..There are bit scattered all through all 6 pages about the "cone of vision" and problems of perspective:
This is a quote:
"If you could use one eye to examine this figure from the true center of projection (directly in front of the central sphere, at a distance equal to the radius of the circle of view, roughly 5cm or 2" from your computer screen), you would discover that all the forms really are in perfect perspective. But because you view the drawing from much farther away (and with both eyes), the spheres and columns appear grossly distorted.

These distortions have distinctive features worth memorizing:

� Horizontal thickening. The spheres and columns far from the direction of view on either side appear thicker than those at the center of view.

� Vertical stretching. The spheres far above or below the direction of view appear vertically elongated.

� Diagonal emphasis. The distortions appear more extreme along diagonal (oblique) directions, where the effects of horizontal thickening and vertical stretching combine.

� Diagonal tilting. Horizontal surfaces, such as the orange flat tops of the columns, appear tilted along the image diagonals rather than forward toward the viewer.

� Peripheral crowding. Equal intervals (such as the spaces between columns) appear smaller near the periphery than at the center of view; eventually the spaces between the columns disappear and the columns seem to overlap.

(Another famous problem, which vexed artists from Leonardo down to Flocon & Barre, is the supposed requirement that lines parallel to each other and to the image plane, such as the top and bottom of a long wall or the sides of a high tower, should taper toward the edges of view. In fact, the perspective rendering of edges does not bow or arc toward the extremes of view, as untested intuitions seem to require, because the increased oblique distance from the viewpoint to the object is exactly matched by the increased oblique distance from the viewpoint to the parallel canvas surface, which results in a constant triangular proportion and a consistent foreshortening of parallel lines toward the sides of the image.)

The common diagnosis for all these perspective distortions is that the width of the drawing is too large a proportion of the 90� circle of view. (This is more often expressed as, "the vanishing points are too close together.") For example, in the office building painting, the width of the paper is equal to the viewing distance (radius of the circle of view), so the format spans a 53� circle of view. As a result, when the drawing is viewed from different distances or angles, we see proportionally large discrepancies between the drawing's and the viewer's diagonal vanishing points.

The solution is to move the vanishing points much farther apart: that is, to place all parts of the principal forms within a more restricted circle of view � equivalent to drawing the objects as they would appear from a viewpoint much farther away. (Once again, we're back to the importance of apparent distance and size to the visual effect of an image.) As a result, the viewing distance to the image is a small proportion of the apparent distance to the principal form, and the drawing can be acceptably viewed from a wider range of viewing distances. The peripheral distortions in rounded forms and crowding of sequential forms are cropped out of the image entirely, and moving toward or away from the drawing represents a change in viewing distance that is small in comparison to the radius of the circle of view.

The practical limit on the field of view is conventionally set at a 60� circle of view � a suggestion made by Piero della Francesca in c.1470 and repeated often since then. In fact, depending on the geometry of the principal form and the location of the vanishing points, a 40� circle of view or less is much more typical.

Leonardo da Vinci devoted many pages in his notebooks (c.1490) to the analysis of perspective distortions, and he especially disliked the exaggerated apparent size of the perspective grid as it reached the ground line of the image plane (for example, as in this image). He recommended painting an object as it appears from a distance of 3 to 10 times its actual dimensions (e.g., a standing figure 1.75 meters tall should be viewed from 5 to 18 meters). This is equivalent to placing the figure within a 19� to 6� circle of view. (In fact, modern vision research has found that most people say an object "fills their field of view" once it occupies approximately a 20� circle of view.)

Such perspective distortions, and the restricted circle of view solution for them, were well known to artists from the beginning of perspective practice. However, these artists also realized that many distortions they could identify from geometrical reasoning were not equally objectionable to a viewer. Apparent distortions in rectangular forms are more objectionable than distortions in curved forms; distortions in the horizontal direction are more obvious than distortions in the vertical direction (in part because the format is usually wider than it is high); distortions in unfamiliar objects are more acceptable than distortions in familiar objects; distortions in the apparent location of vanishing points are more acceptable than distortions in the outline of forms; distortions in "rigorous" perspective drawings are more objectionable than those in "free" drawings; and so on.

As a result, if artists were working with a large fresco or canvas format, or wanted a panoramic effect, they often adopted radical solutions guided by the context of the painting: they would "correct" or disguise perspective distortions wherever they appeared objectionable. This was almost always done for figures, rounded forms, the spacing between columns of a facade, and so on. Often several kinds of "corrections" were used at the same time.

[Brake Check]

Iamgino This was hard for me to understand so I will explain where I was confused..maybe it will help..
REALITY..If you look at the world from any angle..it is round, 3 dimensional space and parallel lines never meet..No Tricks but you can only see part of it at a time.. What you see is a Cone of Vision...For instance you don't have any cone or circle of vision behind your back..That is Reality..No Tricks
GRAPHIC ART...flat 1 or 2 dimensional space representing reality..so "perspective" in a drawing is an illusion..a trick of the eye..
That trick depends in part on where the drawing is viewed from by the person looking at the drawing...For Instance..I have a slight of hand magic trick where I disappear a card ..and if the Viewer is directly in front of me..the trick works...but if the Viewer moves to the side..he sees the card go up my sleeve.. The Viewer's cone of vision changed in relationship to me..in his picture plane..
That is Circle or Cone of Vision..so the trick has a cone of vision..and the illusion or trick of artistic perspective has a cone of vision which cannot be accurately represented by "perspective such as where columns overlap on the edges rather than "look" real...That is an interior "cone of vision" problem and a Viewer "cone of vision" problem..Where the painting is in relationship to the Viwer..the person looking at it in a gallery for instance..which can be solved by different methods explained in the link I posted..
SO..
In Reality..3 dimensional objects are distorted outside the cone of vision..That is for Optometrist to worry about
In Art..1 and 2 dimensional lines and space are distorted to look like a 3 dimensional reality..that is perspective drawing
Cone of vision distortion in reality is something entirely different than the circle or cone of vision in painting.
I hope this helps because this is not easy to understand ..It took me a while to get just these few basics but it all starts falling into place after a while..