Art: Some questions on perspective

# Thread: Some questions on perspective

1. ## Some questions on perspective

Hey guys ^^

I've been trying to teach myself perspective for some time... Some things just don't seem to register... or they do for a while and then after a bit of time I find they make no sense again...
So I've started over, practising all the setups and everything else, watching tutorials, reading books and I hoped I could get some help here as well.

What I'm trying to do now is to deconstruct photographs and try to see what the perspective setup would look like - ie where the station point would be, the vanishing points, what the cone of vision would encompass, but a few things confuse me :
1st thing is - http://commons.wikimedia.org/wiki/Fi...rison_Home.jpg
in this photograph, where would the center point of vision be? I understand that in 1 point perspective it would be where the VP is, so that's easy, but what about in 2 point? Is drawing a 90 degree angle from the VPs the way to do it?
2nd -
http://commons.wikimedia.org/wiki/Fi...tober_2012.jpg
This one is easy to locate the VP and CPV, but how can I locate the station point?

And one more thing - the ground line is supposed to be where the picture plane meets the ground plane - ie where the picture begins, but what if the picture is cropped? Or what if we're unsure if the image is cropped? How can we locate the ground line then?

Thank you very much!

2. I'm no perspective hack, but to me it feels like you're overthinking at least some of your points.
In the first photo, just trace edges that run parallel to each other until they meet off-canvas. That will give you the two VPs for that image (or rather, for that one building as there are multiple VPs of course). They will be located on the horizon line.
And those two things are really (mostly) all you need unless you're going for really advanced stuff.

Your question about a "station point" also confuses me. I did a quick google search, and I think that refers to where the viewer's eyes are? Easy to locate, that's the horizon line. High horizon line means we're looking down, low means we're looking up.

The question about cropped images I don't get at all. Even if I crop an image there'll still be the same horizon line, the same VPs, the same everything.

Last edited by Benedikt; January 16th, 2013 at 02:47 AM.

3. I agree it might be overthinking, but I'm just trying to understand everything that goes into perspective, so I don't have to come back to it again and again and again... I've done that way too many times.
My main concern ,really, is how to get the measuring points, hence why I need the station point. I need the measuring points so I know what a square would look like.

The station point is where the viewer's eye level is, that's right, but it also represents the distance that the viewer is from the picture plane. I think I've figured 2 point out, all you need is a 90 degree angle from the VPs and you locate the station point, but I'm still not sure how that would work for 1 point perspective...

With a cropped picture, the center of vision, which in 1 point perspective is always the center of the picture, could be offset, the ground line would also not be at the bottom of the picture plane any longer... I think that one might be sort of a futile question, but I'm just trying to figure out how to deconstruct the perspective of a picture so that the setup can be used to construct objects that would be in correct perspective....
To be honest, I'm not sure why exactly I'm doing all this, but I figure it might be helpful at some point

4. Originally Posted by volen
To be honest, I'm not sure why exactly I'm doing all this, but I figure it might be helpful at some point
I don't want to deter you from learning and studying, but I have some doubts about that assessment.
Unless you're planning to do absolutely precise technical or architectural drawings with measurements etc. the concepts you're asking about have no practical merit to a painter.

I stand to be corrected by someone with more expertise of course.

5. To be honest, I agree about 90% with that
I do think it's helpful to fully understand what you're doing. To know why the things that we do work, just so you can troubleshoot a problem when needed or have a better appreciation for a particular problem.
Having said that, I find that most people, as you've commented, seem to be getting along pretty well without the need to go in so deep and I think that my over-studying theory might be a weird form of procrastination as I can clearly see that more theory clearly does not give me better results...

Thanks for your comments, you've made me reassess my focus... and to be honest, just looking at your portfolio was enough to make me realize that I was going in the wrong direction

6. Registered User Level 1 Gladiator: Andabatae
Join Date
Dec 2004
Location
France
Posts
2
Thanks
0
Thanked 0 Times in 0 Posts
Follows
0
Following
0
I haven't studied perspective in enough detail to give you an accurate answer, so I'm hoping someone will pick out any flaws in my explanation.
Ignoring the slight curvature on the platform for now, couldn't you simply project the figure on the left to the edge of the platform, project her down so that her feet are at the same level surface as the photographer, and then project that figure as required (as shown by the pink line taken from the horizon through the bottom of the feet). It of course assumes the photographer is the same height as the lady, and I also appreciate she's facing the wrong way! I put her eyes to the vanishing point, as the top of the head would be slightly above the horizon. Let's hope a high speed train isn't about to pass through!

There are no members to list at the moment.

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•