12 – Illusion of Depth & Perspective

Lesson Objectives

At the end of this lesson, students will be able to:

  • use methods of creating illusion of depth in 2D digital images
  • show techniques for working with types of perspective in the digital image
  • work with methods to enhance the depth of field in a digital image

Overview

This week, we focus on the illusion of three-dimensional depth in two-dimensional images. Various ways to express the depth are discussed, including Linear Perspective, Atmospheric Perspective and Depth of Field.

The reason we will focus on this component specifically, is that in order to make realistic manipulated images, rules of perspective must be followed. If your angles are off, like your lighting or noise which we discussed in an earlier lesson, the final image will look fake.

Illusion of Depth in the 2D Image

There are a few ways to show   the illusion of depth through perspective within the 2D image based on the positioning and appearance of subjects within the image.

Linear Perspective

Linear perspective is a system of drawing to create the illusion of depth.    On a fundamental level, the vanishing point is where your eye naturally falls on the horizon line and imaginary straight lines radiate from that point upon which you can base the angles of what you are drawing. This is a super important concept for aligning collaged digital elements as we will see later in this lesson.

wabbit-depth

The rabbit on the left appears closer than the one on the right, because the one on the left is painted larger than the one on the right. This is an example of one-point linear perspective with the one (vanishing) point residing on the horizon line.


Linear perspective is a fundamental tool when you are drawing buildings.   It can get fairly complex with multiple points and sometimes no horizon line at all.

house-perspective
Simple example of one-point perspective with a building and road.

Sometimes the vanishing point is outside the image you are working with and sometimes multiple vanishing points can be found. For example:

multiple vanishing points
Note: the height of the horizon in this case is the line of sight of the viewer.

Foreshortening

Foreshortening is a method used for figures for demonstrating proximity to make part of the figure appear closer than the rest by increasing the proportions of the figure based on linear perspective.

bear foreshorten
The bear’s paw is reaching out towards the viewer (and the fish) appearing closer to the viewer than the rest of the bear because it is larger.

Proximity

birds-depth
One subject physically blocks the other subject.

Focus & Detail

rabbit depth focus and detail
The rabbit on the left appears closer not only because it is larger but also because the rabbit on the right has less detail and is not in focus.

Atmospheric Perspective – Color & Value

bears-depth
The bear on the right appears further away compared to the bear on the left, because its color is faded and similar to the background (Atmosphere Perspective).

Atmospheric perspective is often used for landscapes.

atmospheric perspective
As the hills recede into the distance, they become lighter.

Often several techniques are used at once for maximum effect.

bear atmospheric and linear perspective

Illusion of Depth in the 2D Photo

We can affect photos in a similar way through manipulation.

two arctic foxes
There is a small amount of distance and full depth of field in this photo of two foxes.
two foxes depth of field
Background has been blurred but no other adjustments.
blur on background
Illusion of depth created with blur and darkening of value on background.
adjustments for depth illusion
To create more depth – blur increased in the background, value adjustment to decrease brightness in background, size of second fox diminished.

Illusion of Perspective in the 2D photo

First, please watch this great video on linear perspective. It’s about 10 minutes but please watch it fully. You can change your YouTube settings in the lower right to play at 2x speed if you like.

This week you will be using Photoshop to place some items into a scene in a realistic manner. Unlike the animals that we used in an earlier lesson, these items have angles and will need to be altered for perspective to have a realistic appearance.

The following video is an introduction to what we are doing this week.

I’m including a few detail videos, used with permission, by Miho Aoki, who also teaches this course. She goes into greater detail about the process of examining and fixing many elements that are important to consider when creating illusions in Photoshop. One of the main points here also is constant evaluation of the details of the item placed into a scene and how it relates to the items nearby – is the lighting correct, does the item placed seem too bright, to saturated, have the same amount of noise, the same sharpness? Watch these videos on her process.

Extra Notes on the Free Standing/Hanging Objects:

If you want a flat and rectangle object, it should follow the linear perspective of your background image. If you cannot make the plane look flat, try the following steps,

  1. Locate the horizon line in the background image. It’s the least tilted lines among the lines you see in the image (please refer to the class lecture text above). If there is no flat line, use the heigh of the camera. Do not use lines on the tilted objects, because they don’t follow the same linear perspective. In this kitchen image,   the eye of the photographer is the height and line of the horizon.

    Exif_JPEG_PICTURE

    Kitchen with Lines

  2. All parallel lines should meet at the horizon line. So when you extend the top and bottom lines of the banner, they should meet at the horizon line like shown in the following image,

    Exif_JPEG_PICTURE

    Proper Perspective, two lines meeting at the horizon

    If the lines reach the horizon line but don’t cross at the same vanishing point, the plane is tilted, twisted or not rectangle. Adjust the angle of the plane till the lines meets at one vanishing point.

    Exif_JPEG_PICTURE

    Tilted Plane, two lines crossing the horizon line at different places

Further Reference

There are a gazillion great videos explaining the nitty gritty of perspective. I encourage you to search for and watch these videos if you want to learn more about perspective and how to draw with perspective. This is also something you learn in beginning drawing classes.

Here’s some history of Linear Perspective:

 

 


HOMEWORK

Exercise #12

Step 1: Download one of these background images or you can use one of your choice, as long as there are clear lines of perspective. The file should be 1500-2000 ppi on longest side. (click on image and then drag to your desktop to download full size)

hallway living room conference room subway

Step 2: Create flat images such as, billboards, flyers, signs, banners and writing on a wall, as separated elements as a separate files.

Step 3: Place the flat images (use a minimum of 5) onto the background images.

Do not change the background images.

Here are a few flat images you can use to get started or find/make your own (again, click on the image to grab the full resolution version:

I voted sticker oval sticker bamboo placemat peacerug Van Gogh painting loveVan Gogh painting Van Gogh painting angelvintage poster

 

Step 4: Adjust the colors, perspective, blurriness, noise and other aspects of the flat images  to make them appear to be standing on the ground/floor, hanging from the ceiling or placed/painted on walls in the background images.

Step 5: Save the image and share the Photoshop file with layers in your Google Folder. Also save the image as JPEG for uploading to the website.

Again, the Requirements:

  • Do not change the background image.
  • Make sure you place at least 5 new things of decent size (not tiny).
  • Try more challenging changes, like placing larger objects and non-rectangle signs.
  • Please pay attention to colors, shadows, blurriness, noise contrast, brightness, reflections etc. besides the linear perspective.

Screen Shot 2015-08-31 at 2.49.00 PM

Journal #12

  1. Create a new post  on the course website and  give it the category ‘Exercise  12’².
  2. Upload the JPEG images you  worked on in Exercise 12
  3. Write a short reflection on the processes you used to create your image. Were you successful in creating your image? What do you like about it? How could it be improved? Describe any challenges you encountered.

Discussion

Please comment on at least one other post from last week (Exercise 11 3D and Oral Presentations). Are there any commonalities with your practice that others experience and have shared in their presentations?

Final Project Proposal

Please go to the Final Project instruction page. After reviewing the project, please create a new document in your Google Drive folder   called ‘Final Project Proposal’ and outline the basic idea for what you plan to do. Search for any tutorials you may want to follow and include the link to those tutorials. Include images that you are inspired by as well – anything that will help you work on your project over the next few weeks and help solidify the idea in your mind before you start the process.