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sekopasa
04-07-2006, 04:14 PM
I drawed some gifs for this tutorial i think they explain their self, if you have questions you are welcome.

http://img413.imageshack.us/img413/293/circlepersp7bs.gif

http://img387.imageshack.us/img387/8018/persc12va.gif

http://img422.imageshack.us/img422/2490/persc28be.gif

http://img422.imageshack.us/img422/6835/persc35wh.gif

http://img422.imageshack.us/img422/515/persc49tv.gif

dredsign
04-07-2006, 05:08 PM
really useful!! thanks for this tutorial...

i mostly draw these circles and ellipses by just trying and see if they look right... doesnt always work though... hehe

arisuonpaa
04-07-2006, 07:00 PM
And when drawing with a template, note that the minor axis always points to the vanishing point. This was something really hard for me to understand and still is. Can anyone explain why it does that? It kind of makes the ellipse to tilt a bit..

-Ari

sekopasa
04-08-2006, 07:02 AM
I would try to find a reply to your question but couldnt exactly understand what you mean can you show us some drawing.

Taltos
04-08-2006, 09:43 AM
what i think he means is, that the minor axis of the ellipse is parallel to the "axis" of the circle (think car: a wheel and its axis, mathematically correct: the line going through the center of the circle, perpendicular to it).
in your example, this axis points to the vp.
A very useful/understandable tutorial can be found here (http://www.drawthrough.com/tutorials/ellipses.html). A very detailed text treating perspective here (http://handprint.com/HP/WCL/tech10.html).

arisuonpaa
04-09-2006, 07:38 AM
Thanks sekopasa and Taltos. I realized that every time the circle in perspective seemed to be tilted, I had the degree wrong. I think I could even use ellipses to make perfect squares in perspective, am I right? I have to look into that handprint tutorial. Hope I have enough idle time at work to go through it :D.

-Ari

sekopasa
04-10-2006, 06:18 AM
To use elipses to draw squares is a realy good idea.

But there is elipses in different proportions, the height can be same but it varries in width, will it be possible.

keight
04-10-2006, 02:24 PM
Thank you for sharing this one too. This makes sense now.

Sethelic
02-15-2007, 08:01 AM
Some further questions about ellipses

1. About using Ellipse guides: Doesn't ellipse guides just tell you how much 'exposure'(major axis fixed, minor axis shortens according to tilt) there is? it would be fine for axonometric ellipses, but doesn't perspective circles also foreshorten so how do you use an ellipse guide with Perspective drawing?

2. Does the minor axis of an ellipse in Perspective always align to the VP / thrust axis too?

3. anyone konws of any digital ellipse guide or equivalent?

4. the scott robertson tutorials on drawthrough.com seems to have been taken down, anyone knows where i can find it?

5 If i simply create a perfect circle in a perfect square then use 'free transform tool' in photoshop to Bring the 2 backends of the square together while keeping them aligned to lines extended frm VP, is that an accurate ellipse?
'compressing the two ends of the bounding box to create illusion of
Perspective. I was wondering in this case( attached picture, not drawn to
scale(esp edge length receding towards vp) :

(i read that this digital method of 'squeezing' isn't very accurte?)

Attached below:
http://xs412.xs.to/xs412/07074/perspective.JPG (http://xs.to)

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