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  1. #41
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    Default Re: Perspective Drawing

    perspective, look at #6, page 1 this thread. I still disagree with what you are saying, it sounds like you are intellectualizing why it does or does not work without any proof. The issue really is that you have to move your object or objects around until you find the station point for the view you want while staying within the cone of vision to avoid any obvious distortion. You can go out of of the cone but only with care by being aware of what happens when trying to show an additional object in your scene, and then only showing a small part of the additional object that is now distorted.
    Last edited by wizard509; 10 December 2012 at 03:13 AM.
    Larry a.k.a wizard509

    Never give up. You will never fail, but you may find a lot of ways that don't work.

  2. #42
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    Default Re: Perspective Drawing

    The drawings shown at #6 are two point perspective, they would always have a better impact in three point, but they look fine, I guess they belong to you?

    We could go on here so I want you to do a little test for me, 'please'.

    Stand with your arms outstretched about 24ins apart and your thumbs facing up.

    Look straight ahead between your hands without moving your eyes (remembering that with perspective drawing your eye are fixed) and your thumbs will be a little out of focus. Now bring your hands together about 6ins apart and you can see your thumbs more clearly.

    We use our eyes to look at each thumb to get it in focus, a natural thing to do, but in perspective drawing we cannot do that! Now close one eye (just as you would in perspective) and you will see that the whole subject starts to look distorted until you put your hands closer together. Our brain and the movement of our eyes play a large part in our lives but with perspective drawing we cannot use them. We have to use the best methods which have been proven over the centuries by expanding our Cone of Vision and 30deg works well for small objects and 60deg for large objects. You cannot stick to 30deg in all cases.

    In perspective 'additional objects' should have already been taken care of to plot or work out your Perspective Drawing. Many artists in the technical illustration field may start with drawing the individual pieces i a plan view. you are better off putting it all in a container (or box) to make sure you have not left any additional part off.

    One of the great things about 3D apps, you can reposition your objects without any problem, not so easy with Perspective Drawings, you must get it right the first time.

    You wanted proof. I have drawn 3 images below given you the measurements and using 60deg as my Cone of Vision (the sizes are units so you can use 5 as 5 feet or 5 ins, here I am using it as 5 feet), with 2 point perspective. Please prove me wrong!

    Click image for larger version. 

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    Click image for larger version. 

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    Click image for larger version. 

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    Setback just means the object is setback from the Picture Plane 'x' distance.
    Last edited by perspective; 10 December 2012 at 09:08 AM.

  3. #43
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    Default Re: Perspective Drawing

    You're trying to intellectualize a subject which has rules that are easy to follow. In 2 point perspective you have 2 VP's a horizon line and that's it. Two-point perspective has one set of lines parallel to the picture plane and two sets oblique to it. Parallel lines oblique to the picture plane converge to a vanishing point,which means that this set-up will require two vanishing points.
    Design is thinking made visual.

  4. #44
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    Default Re: Perspective Drawing

    Many artists out there would find your remarks insulting. They have studied perspective and some still find it hard to do. 3D apps come from perspective drawing and to demean them is a hugh insult. Oh Please! It’s guys like you that helped the government close learning facilities because you do not think we should learn the most fundamental part of art.

    This is my first involvement with a forum and I still find statements as yours a shameful way to behave.

    ‘In 2 point perspective you have 2 VP's a horizon line and that's it’, your words.

    Please show us how you measure 2 10ins cubes going off in the distant with one side 34deg, one behind the other with a space of 26ins? If you can do that with 2 VP's and a horizon line I will leave this forum NOW!

  5. #45
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    Default Re: Perspective Drawing

    Quote Originally Posted by Albacore View Post
    In 2 point perspective you have 2 VP's a horizon line and that's it. Two-point perspective has one set of lines parallel to the picture plane and two sets oblique to it. Parallel lines oblique to the picture plane converge to a vanishing point,which means that this set-up will require two vanishing points.
    Not quite. One horizon parallel to the picture plane and two lines parallel to one object. All additional objects in the scene are referenced from that one object, that is unless you want to find the vanishing points for your other object using the same horizon and station point. Yes you can have more than 2 points and still technically have a 2 point perspective. The other points are merely auxiliary points for convience, such as if you have several windows all skewed the same. (They have to be skewed the same or there is no reason for finding the auxiliary point.

    @ perspective.
    Why are you showing a drawn cube in the cone of vision, is that to show that you are using a greator than 30 degee cone?
    #2 looks distorted mainly because there are no other objects in the scene or on the main object to explain to the viewer why it is like it is. I assume the close corner is not the same height as the other to it's left. In fact it must be higher (taller). Something else needs to be shown either on the object or nearby so as not to confuse the viewer.
    "If you can do that with 2 VP's and a horizon line" you can but again you need something shown either on the object or nearby to enplane to the viewer what is happening.

    Why do technical illustrators use 2 point perspective and not 3 most of the time. When hand painting it's a matter of convince, particularly when rendering buildings, mostly because so much has to be redrawn all the time and also because it looks more natural to the layman.
    I don't like your test "Look straight ahead between your hands without moving your eyes (remembering that with perspective drawing your eye are fixed) and your thumbs will be a little out of focus. Now bring your hands together about 6ins apart and you can see your thumbs more clearly.

    We use our eyes to look at each thumb to get it in focus, a natural thing to do, but in perspective drawing we cannot do that! Now close one eye (just as you would in perspective) and you will see that the whole subject starts to look distorted until you put your hands closer together. Our brain and the movement of our eyes play a large part in our lives but with perspective drawing we cannot use them. We have to use the best methods which have been proven over the centuries by expanding our Cone of Vision and 30deg works well for small objects and 60deg for large objects. You cannot stick to 30deg in all cases.' while that may be true, perspective is used to define an object period and that's what it's all about. Perspective drawing is merely a means to an end.

    As for your cube with one vertical side and one 34 deg side that is also possible but it has to be drawn as a real cube and the other points found that way. I can do it, in fact I had to do it all the time. It's all a matter of understanding. I must thank you for this thread because I haven't done any for a very long time and because of you and this thread I now remember a few of the things I had forgotton.
    Larry a.k.a wizard509

    Never give up. You will never fail, but you may find a lot of ways that don't work.

  6. #46
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    Default Re: Perspective Drawing

    Quote Originally Posted by Albacore View Post
    You're trying to intellectualize a subject which has rules that are easy to follow.
    very much so..

    I have a 20 page book on perspective - it contains everything I have ever needed to know that wasn't obvious in the first place, and I picked it up for 50p in a sale


  7. #47
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    Default Re: Perspective Drawing

    I don't visit this site to offend people and I apologise if you took my remark as offensive as all that I was saying that perspective drawing follows simple rules which must be obeyed. To answer "perspective's" question about 2 cubes, you would use measured perspective from a plan view and that is what Larry is stating. I taught technical drawing at a high level for too many years. One area that I found hard to get across to students was how to get the vanishing point of a normal pitched roof building, or an inclined line, this can be done using an auxiliary viewpoint or using a measured elevation. In all there are only 16 simple rules that need to be followed. CAD programmes have taken the calculations out of perspective drawings so the use of rules has realy diminished which means bar simple perspectives none are taught.
    Design is thinking made visual.

  8. #48
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    Default Re: Perspective Drawing

    Well said, Albacore. I hope Perspective has not left TG and especially not because we could do what he did not think possible. After all anything is possible if you just know how, or spend the time to figure it out. And perspective drawing is no different, many times it's simply a matter of finding the points and connecting the dots.
    Larry a.k.a wizard509

    Never give up. You will never fail, but you may find a lot of ways that don't work.

  9. #49
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    Default Re: Perspective Drawing

    one time I had to get perspective spot on was when animating, and again the software did the donkey work thank goodness....

  10. #50
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    Default Re: Perspective Drawing

    Albacore, you have not gasp the idea of perspective with your statement ‘you would use measured perspective from a plan view’, that is not what perspective drawing is about. You would work with elevations, plan, side and top.

    Taking a plan view to create your measurements seems odd and long-winded. Producing a finish perspective drawing for instance of a block of flats, if you are a technical artist, with 12 apartments would be a nightmare if you had to produce or copy a plan view above your work.

    You would simply set-up your measuring points on your Horizon line and every single line you draw is measured from these 2 or 3 points (3 if you are doing 3 point perspective). Your elevations would be by your side for your reference.

    You would be able to pinpoint each light in the ceiling or absolutely anything you wish to do with just 2 or 3 lines, precisely. A draftsperson works with plans, the perspective artist works with measurements taken from plans. The artists working outside sketching is artwork, can produce the same correct drawing once he knows how to us perspective correctly and would not even need plans.

    I think I should also mention that Fine Artist, Still Life and Landscape artists do not work with plans but a good understanding of perspective. As I have said from the start of this discussion, I am here to help so please give me a problem with perspective and I will show you the answer, talking slows down the process of learning.

 

 

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