How to place people/objects in a scene and have them be in the right proportion

[gatw18]

I went through this video and I thought I got it right. My understand is

1. Find the horizon in the main image (the river - I found it with the red line)
2. find the horizon of the other image (for the swimmer on the left the horizon is on her hips)

But she looks too big, doesn't she?

And, assuming the swimmer is correctly placed, for the woman on the right, there's no background information to figure her horison.


Is this correct?

 

[Rich54]

But she looks too big, doesn't she?

When you say she's "too big", then you can always make her smaller. It all depends on where she is positioned in the scene and how far away she's supposed to be.

Here's a woman at the beach. Obviously, the horizon line goes right through her head, just below ear level.
Below that is a garden scene, where I drew a red line estimating the horizon.

To place the woman correctly in the garden, the garden's horizon line should run just below the woman's ears. If she's near us, she will be large. If she's far away, she'll be small. But in all cases the horizon runs at her ear level. I've placed three different sizes of her to illustrate this.

In your example, the second woman (in the blue dress) doesn't have a background where the horizon is obvious. But you can just guess by eye. Are we looking up at her? Are we looking down at her? Are we approximately level with her? The perspective of the woman in the blue dress doesn't seem too different from the surfer woman, so just call it a day and make the horizon the same for both—through the hips.

 

[gatw18]

The perspective of the woman in the blue dress doesn't seem too different from the surfer woman, so just call it a day and make the horizon the same for both—through the hips.

Your example with the woman in the garden really helps. And that's what how I understood it. But I asked about it in reddit and someone said that "based off what I can see, the swimmer would be like 12 ft tall as you have her right now. lol" which made me question the entire thing. But what you just said makes me think my two women are positioned right.

Question: If I want the blue-dress woman to be closer to us, do I make her bigger and always keep her hips in the line

You really helped. Thank you

 

[gatw18]

When

I forgot to ask: How did you com up with the horison in the garden picture. And, I found this image, from Cognitionis


Wouldn't the man be smalller than the statue on the right?

Am I right in saying the room's horizon line is somewhere at his chest at the moment?

 

[thebestcpu]

Hi @gatw18
I am not an expert on finding the horizon line yet this is how I approach it with a scene that has perspective. I find the vanishing point based on several perspective lines that should be parallel to the ground surface. In the image below you can tell the image does not have perfect perspective because the lines of perspective don't converge to a single point yet close. And you will notice that that vanishing point is about at the subects chest level.
Hope this is an approach worth considering for you
John Wheeler

 

[ushere]

Wouldn't the man be smalller than the statue on the right?

how do you know the height of the statue in the first place?

as it is, the inserted element is too big relative to the 'desk'...

 

[Rich54]

Your example with the woman in the garden really helps. And that's what how I understood it. But I asked about it in reddit and someone said that "based off what I can see, the swimmer would be like 12 ft tall as you have her right now. lol" which made me question the entire thing. But what you just said makes me think my two women are positioned right.

Question: If I want the blue-dress woman to be closer to us, do I make her bigger and always keep her hips in the line

This might be over-simplifying, but... once you decide where the woman is standing, then put her feet on that spot. Then adjust her size so that her hips are at the horizon line.

If you want the woman in the blue dress to be closer, then keep her hips at the horizon line and then make her as large as you want. In the most extreme example, she might be standing six inches from the camera, in which case she is so large that we would see her hips but probably not her head and feet.

For estimating the horizon line of the garden, I looked at lines that converge to the vanishing point. In perspective drawing, you set the horizon line and the vanishing points, similar to this image here:




For the garden scene, I looked at the angle of the hedges, the wall and the smaller hedges (all highlighted in red). Where these lines converge—which is off the page—is the vanishing point, which sits on the horizon line. I just estimated it by eye, so I may be off a bit, but you can figure it out exactly be extending the three red lines to the point where they all meet.

 

[gatw18]

@thebestcpu would you say that the figure should be smaller, small enough so that his eye is in line with the vanishing point?

Is it a good (enough) rule that if I can't determine the horizon line for my subject I should just place their eye around the horizon line?

(sorry if these a basic questions)

 

[gatw18]

how do you know the height of the statue in the first place?

as it is, the inserted element is too big relative to the 'desk'...

It was a hunch. For some reason I didn't notice the desk . Though if we were to shrink him so his knees fit under the desk, the statue would look about the height I was thinking.

 

[gatw18]

@Rich54 Thanks so much for the explanation, you've been very helpful.

 

[thebestcpu]

@thebestcpu would you say that the figure should be smaller, small enough so that his eye is in line with the vanishing point?

Is it a good (enough) rule that if I can't determine the horizon line for my subject I should just place their eye around the horizon line?

(sorry if these a basic questions)

Hi @gatw18

Again I am not the expert on this subject yet will provide my answer on how to place a subject into a composition of have it look more realistic from where to put the horizon line through the subject and also the sizing of the subject.

You suggested approach will work in quite a few situations yet certainly not all. Here is where it will work.
a) When the camera shot of the composite was taken parallel to the ground i.e. pointing at the true horizon
b) When the camera shot of the subject was taken parallel to the ground and at the same approximate height above the ground of the subject as the subjects eyes.

Both of the above are not an uncommon situation and your approach will work in those case yet only when those conditions are met. It will just look off otherwise.

As far as size of the subject there are a couple approaches
a) The subject can be sized relative to other objects at the same distance from the camera base on the relative size of the subject to those objects.
b) There are not always other objects at the same distance. In those cases you use the perspective lines which show you how much the subject should grow or shrink in the image along the perspective lines to a known size object closer or further away or likewise using the perspective lines to resize an object larger or smaller (closer or futher away) to match the location of the subject for the relative comparison. There are more complex cases yet will leave it at this point for your consideration

Hope this helps
John Wheeler