Upcoming Deadlines Homework #13 – Creating Stereoscopic 3D Images Due Wednesday, December 8 th (Next week) 20 points (10 points if late) Final Exam - Tuesday, December 14 th 12:15-2:30pm in this room. For full schedule, visit course website: ArtPhysics123.pbworks.com Please take a clicker and a bag of 3D glasses

Final Exam Final Exam will have of 10 short essay questions on material covered in lecture. Final exam counts for 50 points. See course website for copy of last semester’s final exam. You may bring one page of notes double- sided (or two pages single-sided) to the exam.

Final Exam Sample Questions: * What is “drag” in animation? Give an example to illustrate your definition. What physics principle causes “drag” to occur? * Explain the difference between reflection and refraction. Also give two examples of each. Final Exam is on: Tuesday, December 14 th 12:15-2:30pm in this room

Activating your Clicker * Turn on your clicker. * Enter the channel number or letter for joining this class. Hit Enter/Send key. * Clicker should read AP123GF10 * Type in your student ID; hit Enter/Send. Clicker is now ready to use; leave it on. Hit any key to wake the clicker from sleep mode.

Survey Question This course has four parts; which part was the least interesting for you: A)Basic Animation (Falling, etc.) B)Character Animation (Walks, etc.) C)Effect Animation (Waves, etc.) D)Lighting (Shadows, Color, etc.) E)About the same for all four

Review Question Red Cone Green Cone Blue Cone What color do you see when your eye receives both red and blue photons? A)Yellow B)Green C)Magenta D)Cyan E)White

Review Question C) Magenta This is nicely demonstrated with the spinning Maxwell disk.

Review Question I’m a little excited Yawn. When white light is added to a pure hue, the value (brightness) increase but what decreases? A)Saturation B)Gamma C)Opponency D)Contrast E)Chromatic Flavor I’M VERY EXCITED! Pure Red Light Pink Light I’m a little excited I’M VERY EXCITED!

Saturation & Value High Value and Low Saturation Low Value and High Saturation As lighting conditions change, value and saturation usually vary together. Value Saturation Value Saturation

Review Question If you stare at a red cross for a few seconds and then look at a white wall, the after-image you see is cyan. What color is the after- image if the cross is blue? A)Red B)Yellow C)Green D)Magenta E)Orange Red cross After- image Blue cross

Negative After-image Stare, unfocused, at the red cross for 10 seconds then look at white wall

Negative After-image Yellow

Additive Complements After-image of blue cross is yellow since blue cone gets tired so when white light excites all three cones, red & green cone signals are stronger than blue cone. Yellow = White - Blue R G B

Stereoscopic (3D) Images

Seeing Depth

Terminology: Steroscopic vs. “3D” The term “3D Animation” has been used for years to refer to computer animation created with programs (like Maya) that manipulate objects in 3D, though the rendered image is in 2D. To avoid confusion, the term “Stereo 3D” is used.

Perception of Distance Visual cues for distance and depth: Occlusion Geometric Perspective Known sizes and patterns Lighting and shadows Atmospheric Perspective Focus and Depth of Field Relative motion Stereopsis

Occlusion The simplest way that we perceive distance is by the fact that closer objects occlude (hide) objects behind them. Even in this surreal painting we immediately see the boy as being closer to us than the woman because he partially blocks our view of her. Detail from The Madonna of Port Lligat, Salvador Dali, 1950 Notice that the shadow tells us that he is hovering above her lap.

When occlusion is incorrect, we are very cognizant that something is wrong. Distorted Occlusion Carte Blanche, René Magritte (1965)

Manipulating Occlusion The image is disturbing but the reason isn’t immediately apparent. Detail from Waterfall, M.C. Escher, 1961

The artist has distorted the occlusion, disrupting our ability to judge distance. This is not accidental; this artist made the composition with this effect in mind. Manipulating Occlusion Detail from Waterfall, M.C. Escher, 1961 This channel of water needs to be behind the lower part of the right tower.

Perspective The difference is the introduction of visual perspective by Filippo Brunelleschi of Florence. Objects in the distance look smaller as determined by geometric rules. Florence, Italy

Renaissance Paintings Marriage of the Virgin, Raphael, 1504 The use of perspective in painting was introduced during the Italian Renaissance around Road to Calvary, Martini, 1315

Geometric Perspective We can check that the persons in the foreground and background are the same height by drawing lines back to the horizon. Horizon

Distorted Perspective Modern painters sometimes distort the perspective for dramatic effect. Mystery and Melancholy of a Street, de Chirico, 1914 The two buildings converge to two different horizons. This feels weird and unnatural, which is what the artist intended (note the title of the painting).

SJSU Dining Commons Painting This campus painting shows the Business Tower with the Art building on the right. What’s wrong with it? Painting is currently hanging in the SJSU Dining Commons

SJSU University Room Painting Horizon Using geometric perspective, let’s see how tall the red-headed person must be as compared with the door of the Art building. Pretty tall!

Known Sizes and Patterns Being familiar with tea sets we know that the cups are in front and the pot is in back. Being familiar with aircraft we know this photo is fake.* *Only it’s not (St. Maarten airport).

Forced Perspective Known size is a weak visual cue for depth, easily overridden by other visual cues. Ames room

Lighting and Shadows A Trompe-l'œil (trick the eye) fools us into seeing a 2D painting as being 3D by using lighting and shadows.

Atmospheric Perspective Objects in the distance have a bluish, unsaturated color due to atmospheric scattering of blue light. More effective for indicating great distances.

Focus & Depth of Field Perspective, with respect to painting, is divided into three parts… the first is the diminution in the size… the second is that which deals with the diminishing in color… the third is the diminution of the distinctness of the shapes and boundaries… Leonardo Da Vinci Our eyes adjust focus, tensing or relaxing the lens depending on the distance to the object we’re looking at. Objects that are very far or very close are difficult to focus clearly.

Relative Motion Relative motion is a visual cue for depth that can only be used for animated images. Objects far away move less distance in the visual plane than objects nearby. Frame 717 Frame 718 Cactus is close Mesa is far Mountains are very far

Parallax & Relative Motion The blue object is farther away because it has a smaller parallax angle (at the apex of the triangle) than the red object. ) ) MOTION The closer red pillar moves further in the field of view.

Parallax & Stereopsis Stereoscopic vision uses the same parallax effect, comparing the view as seen by the left and right eye. ) ) Left Eye Right Eye

Occlusion Revelation Occlusion is a powerful visual cue for depth and stereoscopic vision can use it if one eye sees part of an object that the other eye cannot. Left Eye Right Eye Left eye sees only front and top of cube. Right eye also sees around the side of the cube.

Stereoscope In 1861, Oliver Wendell Holmes, Sr. created a popular, inexpensive stereoscope design. In 1838, Charles Wheatstone explained binocular vision and constructed a stereoscope to allow a person to see 3D images from a pair of 2D drawings.

Anaglyph Glasses A simple way to present a separate view to each eye of the same image is to use filters of a color complement pair. Blue/Yellow Green/Magenta Red/Cyan R Y B G M C

Demo: Anaglyph Glasses Put on a pair of Green/Magenta glasses, close one eye, and look at a second pair (or look in the mirror). Can also look at the pairs shown below. No filter Magenta filter Green filter

Red/Cyan Anaglyph Red (Left) Cyan (Right) The most common type of anaglyph glasses use red/cyan pair of filters. One disadvantage is that some displays (like TVs) do not have good spectral properties for the green LED, which causes cross-talk (e.g., the right image is seen by both eyes). Transmission % Wavelength

Green/Magenta Filters The green/magenta combination is better for viewing stereo 3D movies on televisions. Another option is blue/yellow, called ColorCode 3D. Green (Left) Transmission % Magenta (Right) Transmission %

House of Wax (1953) House of Wax was one of the early 3D films of the 1950’s and it had many gimmicks to show off the 3D effect, such as in this paddle ball scene. Homage scene appears in Monsters vs. Aliens (2009). Red/Cyan

Negative Parallax House of Wax (1953) Foreground Image (Negative Parallax) Background Image (Positive Parallax) Objects can appear to come out of the screen and into the audience by use of negative parallax.

Negative Parallax Please put on your Red/Cyan glasses

Stereopsis vs. Occlusion Please put on your Red/Cyan glasses Depth perception by stereopsis is destroyed when overridden by occlusion.

This bookshelf sidewall is at screen depth Green/Magenta Glasses

Telephone is at screen depth Green/Magenta Glasses

Retinal Rivalry When one of the two images is outside the cone of vision for either eye the viewer becomes fatigued due to the brain’s attempt to resolve the image (retinal rivalry). From 3D Movie Making: Stereoscopic Digital Cinema from Script to Screen by Bernard Mendiburu

Homework #13 Creating stereoscopic 3D images. For this assignment you will create at least three different stereoscopic images from photographs. At least one of the images should have you appearing in the photo and at least one of the images should be a recognizable location on campus. You will be graded on the composition so plan your scenes to make them interesting (especially for 3D).

Stereo 3D Photos with PhotoShop Steps for creating stereo 3D photos in PhotoShop: 1)Snap a photo, move 3 inches to the right, take a second photo. Avoid having objects closer than a yard away from the camera and no moving objects! 2)Open both images in PhotoShop. Hold the shift key and drag the right eye image on to left eye image. 3)Rename the layers “Right Eye” and “Left Eye”; make sure the Right Eye layer is on top. 4)Double click the Right Eye thumbnail to open the Blending Window. In Advanced Blending uncheck the Red Channel for Red/Cyan glasses (or Green Channel for Green/Magenta glasses).

Stereo 3D Photos with PhotoShop Uncheck the Red Channel Select Right Eye Layer

Homework #13 Upload your photos to your blog in an entry entitled “Creating Stereoscopic 3D Images” Optional: You can also create a pair of stereo-ready images in Autodesk Maya by rendering a scene for one image, then shifting the camera position and rendering the second image. Bonus Points: Create a 3D animated short, either by stop motion or in Maya. Ten bonus points for a good animation; twenty bonus points for a great one. Due Wed., December 8 th points (10 points if late)

ChromaDepth Another system for creating 3D images. On a black background, red will appear closest, blue furthest, and the other colors will fall in- between according to their place in the rainbow (red, orange, yellow, green, blue).

Chromatic Aberration Chromatic aberration causes "fringes" of color along boundaries that separate dark and bright parts of the image. The focal point of a lens is different for different wavelengths of light so different colors are focused at different positions. This shift is used to create parallax for the different colors in ChromaDepth. ChromaDepth system relies on an optical effect known as chromatic aberration. Photo with chromatic aberration

Next Lecture Stereo 3D, cont. Keep the 3D glasses bag to do your homework Bring the bag to class on Monday Please turn off and return the clickers!