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Forced perspective

From Wikipedia, the free encyclopedia

The Potemkin Stairs in Odessa extend for 142 metres (466 ft), but give the illusion of greater depth since the stairs are wider at the bottom than at the top
The Potemkin Stairs in Odessa extend for 142 metres (466 ft), but give the illusion of greater depth since the stairs are wider at the bottom than at the top
The forced perspective gallery at the Palazzo Spada in Rome by  Francesco Borromini, 1632. The 8.6-metre (28 ft) long gallery gives the illusion of being around four times the length.[1]
The forced perspective gallery at the Palazzo Spada in Rome by Francesco Borromini, 1632. The 8.6-metre (28 ft) long gallery gives the illusion of being around four times the length.[1]

Forced perspective is a technique which employs optical illusion to make an object appear farther away, closer, larger or smaller than it actually is. It manipulates human visual perception through the use of scaled objects and the correlation between them and the vantage point of the spectator or camera. It has applications in photography, filmmaking and architecture.

YouTube Encyclopedic

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  • Prospettiva trompe-l'oeil forced perspective optical illusion of Francesco Borromini (manortiz)
  • How to Create a Hobbit-Sized Illusion

Transcription

Hi! John Hess from Filmmaker IQ.com and in today’s lab we’re going to jump into the underlying fundamentals of everyone’s favorite in camera shrinking effect: Forced Perspective and put a woman inside a martini glass. Forced Perspective is just an optical illusion to make an object appear larger or smaller, or closer or farther than it actually is by carefully controlling distance and vantage point. Today we’ll focus just on changing size, but forced perspective does have a lot of application in set design. The basic concept of forced perspective is pretty easy to grasp. The farther away something is, the smaller it will appear. So you just have to carefully arrange align objects at different distances to create the illusion that the objects are in the same space even though they’re not - but how does it work scientifically? To understand it we have to turn to some basic geometry. Let’s imagine a viewpoint and work in 2 dimensions. We can draw a circle around the viewpoint which represents the entire field view - all 360 degrees. Now let’s say we have this box - how big will this box appear from the viewpoint? To define the size, let’s draw tangent lines from each side of the box to the viewpoint. This resulting angle is how many degrees the box fills up in our field of view - degrees is how we measure the apparent size of an object from our vantage point. Notice that the closer the box is to the viewpoint, the larger the angle, the more degrees of our field of view it will cover. Now to figure out what this angle is, we’ll use a bit of basic trigonometry, we can split this isosceles triangle created by our tangent lines into two right triangles and use the arctan or inverse tangent to figure out the resulting angle. The equation breaks down to 2 times inverse tangent of (the distance to the object divided by 2 times the width of the object) This resulting number is in radians - a whole circle is 2 pi - so each 1 unit radian is about 57 degrees. Using this equation we can determine the appearance of two objects of different distances and sizes. Let’s use an extreme example from the film Apollo 13 where Jim Lovell played by Tom Hanks covers the moon with his thumb. We know that the moon has a diameter of 2,159 miles and is about 238,900 miles from the Earth. Plug these values into our equation and convert from radians and we get about ½ degree. My thumb is three quarters of inch and my arm is about 28 inches long. So holding out my arm, My thumb is about 1.5 degrees - almost three times wider than the moon! Before moving on I want to point out that the angle of view equation be estimated pretty accurately by a much simpler function: width divided by distance. As you can see in this plot, the equations yield pretty much identical results for any distance greater than 2 times the width - which is true in almost all practical applications. So now can mathematically predict size relationships between two different objects at specific distances. The next challenge is to capture that relationship with a lens and sensor. The first concern is framing. We generally describe lenses by their focal length but lenses can also be described by the field of view they cover - the total viewing angle. There are two aspect that play into a lens’ field of view: Focal Length and the sensor size. The equation for finding the field of view is 2 inverse tangent of dimension of the sensor along one axis divided by 2 times the focal length - looks very familiar doesn’t it? Again this outputs radians so we have to convert that to degrees. Now I need to make one really quick side note to dispel a very common myth when it comes to lenses - that long focal lengths compress images while short focal lengths expand space. The lens is doing no such thing. All the focal length does is determine the field of view on the camera side, the compression you see in a high focal length shot is caused by distance to the object! The greater the distance to the object, the less perspective plays a role and hence the more compressed the image. In order to frame a far away shot we need to use a higher focal length. The closer the object, the more exaggerated small distances become. Because closer objects cover more of our field of view, we have to use a wide angle lens. So that’s where the confusion comes in - it’s not the focal length, it’s the distance that compresses perspective. This is of course fundamental to the Dolly Zoom effect. But back to forced perspective. Now we know how to mathematically determine the angle our objects cover and we know how to match the framing using our focal length and sensor size. Now we get to the most challenging aspect of creating forced perspective: and that’s focus. We have to find a focus point and aperture setting that will create a depth of field where both our near object and our far away object are both sharp. Now if we are trying to create a forced perspective image with something large and far away - like these Leaning Tower of Piza images - we could easily utilize the hyperfocal distance - which if you’ve watched our Hyperfocal Distance lab, puts everything from half the hyperfocal distance to infinity in focus. But Hyperfocal distance won’t work on miniatures that you place close to the camera. When it comes to finding the right mix of distance and lens settings there is one rule of thumb. Wide angle lenses work better because they have a deeper depth of field than telephoto lenses given the same aperture settings. For instance a 50mm shooting on Full Frame focusing at 10 feet at F8 would only have a depth of field of 6.28 feet. But a 35mm on the same sensor shooting 10 feet at F8 would have a depth of field of 18.1 feet - a huge difference. So now we’re on kind of a balancing act. Wide angle lenses give us the depth of field we need but the field of view may be too wide for our subject. In this case, we can control the field of view by altering the crop - physically cropping in on an image or by using a smaller sensor camera. Now I’ve been purposely speaking in generalities to convey the concept as universally as possible. Let’s walk through this forced perspective example to see the real challenges of getting all this to work On a film set, the Martini shot is the last shot setup of the day because the next shot would be out of a glass at the bar. Well let’s make that a literal Martini shot. The first step is to figure out the scale between the martini glass and the talent. After sitting with the martini glass and doing some mental visualizations, I eventually decided on 1/8th scale. I needed to make the glass eight times bigger or the talent eight times smaller. This means whatever distance I have the martini glass, I had to have the talent 8 times further away. Before I broke out the cameras, I created a handy spreadsheet to calculate angle of view and mathematically prepare for the shoot. Object A is my Martini Glass with is 7.5 inches tall. Object B would be how tall I wanted the martini glass after I blow it up. Since I have a scale of 8, that value would be 60 inches or 5 feet. My studio has about a good 30 to 35 feet to work with so I set my talent at a distance of 20 feet from my lens - or 240 inches. Reversing the scale, one eighth of 240 inches is 30 inches and that’s where I’ll put my martini glass. At this distance the martini would cover about 15 degrees of my vertical field of view. Now onto selecting the right lens -I found that a 70mm lens on my full frame Canon 5D mk II would give me a 20 degrees of vertical angle - just enough to cover the subject with room to spare. But… and here’s the real frustrating thing: If I shot 70mm even at f22: if I focused at 11 feet - the talent would be in focus but my martini glass would be out of focus. If I focused on the martini glass, then my deph of field would still only be half a foot even at f22 - and that’s not to mention we lose sharpness at this really small apertures. So the 70mm is out. Using my depth of field calculator I tried a bunch of focal lengths until I found that a 30mm lens shooting f/18 and focusing to 4.5 feet would give me a near depth of field limit of 2.5 feet and far limit of 26 feet - perfect. But my vertical field of view with that lens would be 43 degrees - almost three times the field of view of my martini glass and model - so I would have to crop in. If I crop in, I should use a smaller circle of confusion - lets say I crop in 2x. My Circle of confusion is now 0.015 and now my depth of field is shallower. So back to shooting a wider lens. Eventually I find that a 20mm at f18 will do the trick. Cropping an image is acceptable for a photo with high resolution to begin with but not so much for motion picture especially if I’m starting with HD. But what if instead of cropping in, I used a crop sensor? Redoing the numbers for my Blackmagic Cinema Camera values I find that 18mm at f/13 will cover the distance. Now at 27 degrees vertical which would comfortably frame my martini glass plus one extra stop which means less diffraction and less light needed on the set. The numbers I gave you here are my final results - I did plug in a lot of different values to see what worked… but the amazing thing is I could pretty much visualize everything on paper and avoid the scary pitfall of not having the right lens combination on on set. Keep in mind though that although we can calculate depth of field precisely, whether something appears sharp or not is still rather subjective - there is some tolerance for error. Now it’s a matter of executing the plan. I measured the martini glass and scaled up the proportion to make a posing rig for the model to rest on out of steel square pipe. At first I tried just putting this triangular posing rig on the floor but I ran into a problem. In order to sell the effect, I have to have the both front and back rims of the martini glass in line with the lens. I do have a cheater martini glass which I was able to cut in half but that won’t hold liquid obviously. I needed to raise my posing rig but by how much? Well the answer came from good old basic geometry class again. If I know the height of my martini glass and I know the distance to the camera - this is just a similar triangles problem - so I welded on an additional base with 14” of height and micro adjusted with some square wood I had laying around. For padding on the 1 inch square pipe I went with pipe insulation which is pretty much the same thing as a pool noodle but in black. Now to light this monstrosity. Shooting at f11 and higher meant I needed a ton of light. For the foreground martini glass, this wasn’t so hard. I just put a couple LEDs and a 500 watt tungsten fixture with CTB gel - I kept everything daylight balanced because I knew I would use strobes for photos. By keeping the lights really close, by the distance rule we can maximize their illumination effect. Lighting the talent in the background would prove to be a little trickier. For shooting still images, I fired off two strobes. But for motion picture I needed to bust out the big guns, a 2000 watt light with a daylight blue gel. I kept this close and flagged them out of view using strips of material near the camera. And that is it, a martini shot created in camera with forced perspective based on some simple mathematics. Now what I just walked through took a lot of math and planning to get just right. Obviously you can eyeball the effect and come away with pretty decent results. I shot these changing up the perspective on the fly. But the math does matter if you’re working with miniatures and want to stay consistent from shot to shot. Of course all this work begs the question - wouldn’t it be easier to just greenscreen the thing and do it in post? Well maybe- if you’re careful you can achieve results that are as good or even better without having the challenges of shooting with deep focus. For instance, because of the distance, we’re not seeing the talent inside the liquid, such a thing would be a trivial fix if we shot it on greenscreen. Now I won’t say this effect can’t be duplicated in a composite but there is something fun and exciting about getting it in camera. Every special effect shot you encounter will need it’s own tailored solution. So give forced perspective a serious try. Even if you never use it again, the discipline of understanding perspective, lenses, and focus will prove to be a strong foundation in your quest to making something great. Check out links in the description for more on this subject, including a copy of my forced perspective spreadsheet - I’m John Hess, and I’ll see you at Filmmaker IQ.com

Contents

In filmmaking

One example of forced perspective is a scene in an action/adventure movie in which dinosaurs are threatening the heroes. By placing a miniature model of a dinosaur close to the camera, the dinosaur may be made to look monstrously tall to the viewer, even though it is just closer to the camera.

Forced perspective had been a feature of German silent films and Citizen Kane revived the practice.[2] Movies, especially B-movies in the 1950s and 1960s, were produced on limited budgets and often featured forced perspective shots.[citation needed]

Forced perspective can be made more believable when environmental conditions obscure the difference in perspective. For example, the final scene of the famous movie Casablanca takes place at an airport in the middle of a storm, although the entire scene was shot in a studio. This was accomplished by using a painted backdrop of an aircraft, which was "serviced" by dwarfs standing next to the backdrop. A downpour (created in-studio) draws much of the viewer's attention away from the backdrop and extras, making the simulated perspective less noticeable.

Role of light

Early instances of forced perspective used in low-budget motion pictures showed objects that were clearly different from their surroundings: often blurred or at a different light level. The principal cause of this was geometric. Light from a point source travels in a spherical wave, decreasing in intensity (or illuminance) as the inverse square of the distance travelled. This means that a light source must be four times as bright to produce the same illuminance at an object twice as far away. Thus to create the illusion of a distant object being at the same distance as a near object and scaled accordingly, much more light is required. When shooting with forced perspective, it's important to have the aperture stopped down sufficiently to achieve proper DOF (depth of field), so that the foreground object and background are both sharp.

Since miniature models would need to be subjected to far greater lighting than the main focus of the camera, the area of action, it is important to ensure that these can withstand the significant amount of heat generated by the incandescent light sources typically used in film and TV production.

In motion

Peter Jackson's film adaptations of The Lord of the Rings make extended use of forced perspective. Characters apparently standing next to each other would be displaced by several feet in depth from the camera. This, in a still shot, makes some characters appear much smaller (for the dwarves and Hobbits) in relation to others.

If the camera's point of view is moved, then parallax would reveal the true relative positions of the characters in space. Even if the camera is just rotated, its point of view may move accidentally if the camera is not rotated about the correct point. This point of view is called the 'zero-parallax-point' (or front nodal point), and is approximated in practice as the centre of the entrance pupil.

An extensively used technique in The Lord of the Rings: The Fellowship of the Ring was an enhancement of this principle which could be used in moving shots. Portions of sets were mounted on movable platforms which would move precisely according to the movement of the camera, so that the optical illusion would be preserved at all times for the duration of the shot. The same techniques were used in the Harry Potter movies to make the character Hagrid look like a giant. Props around Harry and his friends are of normal size, while seemingly identical props placed around Hagrid are in fact smaller.

Comic effects

Use of forced perspective with the Leaning Tower of Pisa is popular in tourist photography.
Use of forced perspective with the Leaning Tower of Pisa is popular in tourist photography.
Forced perspective of giant beer can model shown "perched" on top of a person's hand.
Forced perspective of giant beer can model shown "perched" on top of a person's hand.

As with many film genres and effects, forced perspective can be used to visual-comedy effect. Typically, when an object or character is portrayed in a scene, its size is defined by its surroundings. A character then interacts with the object or character, in the process showing that the viewer has been fooled and there is forced perspective in use.

The 1930 Laurel and Hardy movie Brats used forced perspective to depict Stan and Ollie simultaneously as adults and as their own sons.

An example used for comic effect can be found in the slapstick comedy Top Secret! in a scene which appears to begin as a close-up of a ringing phone with the characters in the distance. However, when the character walks up to the phone (towards the camera) and picks it up, it becomes apparent that the phone is extremely oversized instead of being close to the camera. Another scene in the same movie begins with a close-up of a wristwatch. The next cut shows that the character actually has a gargantuan wristwatch.

The same technique is also used in the Dennis Waterman sketch in the British BBC sketch show Little Britain. In the television version, oversized props are used to make the caricatured Waterman look just three feet tall or less.

In The History of the World, Part I, while escaping the French peasants, Mel Brooks' character, Jacques, who is doubling for King Louis, runs down a hall of the palace, which turns into a ramp, showing the smaller forced perspective door at the end. As he backs down into the normal part of the room, he mutters, "Who designed this place?"

One of the recurring The Kids in the Hall sketches featured Mr. Tyzik, "The Headcrusher", who used forced perspective (from his own point of view) to "crush" other people's heads between his fingers. This is also done by the character Sheldon Cooper in the TV show The Big Bang Theory to his friends when they displease him.

In the making of Season 5 of Red vs. Blue, the creators used forced perspective to make the character of Tucker's baby, Junior, look small. In the game, the alien character used as Junior is the same height as other characters.

The short-lived Internet meme "baby mugging" used forced perspective to make babies look like they were inside items like mugs and teacups.[3]

In architecture

Forced perspective in the Roman Emperor Constantine's Aula Palatina - Trier: The windows and the coffer in the apse are smaller, and the apsis has a raised floor.
From the outside, the true size of the apsis windows is apparent.

In architecture, a structure can be made to seem larger, taller, farther away or otherwise by adjusting the scale of objects in relation to the spectator, increasing or decreasing perceived depth.

For example, when forced perspective is used to make an object appear farther away, the following method can be used: By constantly decreasing the scale of objects from expectancy and convention toward the farthest point from the spectator, an illusion is created that the scale of said objects is decreasing due to their distant location. In contrast, the opposite technique was sometimes used in classical garden designs and other "follies" to shorten the perceived distances of points of interest along a path.

The Statue of Liberty is built with a slight forced perspective so that it appears more correctly proportioned when viewed from its base. When the statue was designed in the late 19th century (before easy air flight), there were few other angles from which to view the statue. This caused a difficulty for special effects technicians working on the movie Ghostbusters II, who had to back off on the amount of forced perspective used when replicating the statue for the movie so that their model (which was photographed head-on) would not look top-heavy.[4] This effect can also be seen in Michelangelo's statue of David.

Through depth perception

The technique takes advantage of the visual cues humans use to perceive depth such as angular size, aerial perspective, shading, and relative size. In film, photography and art, perceived object distance is manipulated by altering fundamental monocular cues used to discern the depth of an object in the scene such as aerial perspective, blurring, relative size and lighting. Using these monocular cues in concert with angular size, the eyes can perceive the distance of an object. Artists are able to freely move the visual plane of objects by obscuring these cues to their advantage.

Increasing the object's distance from the audience makes an object appear smaller, its apparent size decreases as distance from the audience increases. This phenomenon is that of the manipulation of angular and apparent size.

A person perceives the size of an object based on the size of the object's image on the retina. This depends solely on the angle created by the rays coming from the topmost and bottommost part of the object that pass through the center of the lens of the eye. The larger the angle an object subtends, the larger the apparent size of the object. The subtended angle increases as the object moves closer to the lens. Two objects with different actual size have the same apparent size when they subtend the same angle. Similarly, two objects of the same actual size can have drastically varying apparent size when they are moved to different distances from the lens.[5]

Calculating angular size

Angular Size depiction.
Angular size, distance and object size.

The formula for calculating angular size is as follows:

in which θ is the subtended angle, h is the actual size of the object and D is the distance from the lens to the object.[6]

Techniques employed

  • Solely manipulating angular size by moving objects closer and farther away cannot fully trick the eye. Objects that are farther away from the eye have a lower luminescent contrast due to atmospheric scattering of rays. Fewer rays of light reach the eye from more distant objects. Using the monocular cue of aerial perspective, the eye uses the relative luminescence of objects in a scene to discern relative distance. Filmmakers and photographers combat this cue by manually increasing the luminescence of objects father away to equal that of objects in the desired plane. This effect is achieved by making the more distant object more bright by shining more light on it. Because it is known that luminance decreases by ½d (d is distance from the eye), artists can calculate the exact amount of light needed to counter the cue of aerial perspective.[7]
  • Similarly, blurring can create the opposite effect by giving the impression of depth. Selectively blurring an object moves it out of its original visual plane without having to manually move the object.[8]
  • A perceptive illusion that may be infused in film culture is the idea of Gestalt psychology, which holds that people often view the whole of an object as opposed to the sum of its individual parts.[9]
  • Another monocular cue of depth perception is that of lighting and shading. Artists also use lighting to establish shadows. Shading in a scene or on an object allows the audience to locate the light source relative to the object. Making two objects at different distances have the same shading gives the impression that they are in similar positions relative to the light source, and therefore, they are apparently much closer than they are in actuality.[10]
  • A simpler technique employed by artists is that of manipulating relative size. Once the audience becomes acquainted with the size of an object in proportion to the rest of the objects in a scene, a photographer or filmmaker can replace the object with a larger or smaller replica to change another part of the scene's apparent size. This is done frequently in movies. For example, to aid in the appearance of a person as a giant next to a "regular sized" person, a filmmaker might have a shot of two identical glasses together, then follow with the person who is supposed to play the giant holding a much smaller replica of the glass and the person who is playing the regular-sized person holding a much larger replica. Because the audience has seen that the glasses are the same size in the original shot, the difference in relation to the two characters allows the audience to perceive the characters as different sizes based on their relative size to the glasses they are holding.[11]
  • A monocular cue easily taken advantage of by painters is the trend for the color of objects in the distance to be shifted more towards the blue end of the spectrum, while closer objects' colors are shifted toward the red end of the spectrum. A painter can give the illusion of distance by adding blue or red tinting to the color of the object he is painting.[11] The optical phenomenon is known as chromostereopsis.

Examples

In film

Forced perspective has been employed to create dwarfs and giants in film, such as Hagrid, the half-giant in the Harry Potter series, and hobbits in the Lord of the Rings series.

In reality, there is only a 5-inch height difference between Elijah Wood, 5′6″, and Ian McKellen, 5′11″, the actors playing Frodo and Gandalf in The Lord of the Rings films; however, the use of camera angles and trick scenery and props creates the illusion of a much greater difference in size and height.

Numerous camera angle tricks are also played in the movie  Elf to make elf characters in the movie appear smaller than human characters.

In art

Still life with a curtain
Still life with a curtain

In his painting entitled Still life with a curtain, Paul Cézanne creates the illusion of depth by using brighter colors on objects closer to the viewer and dimmer colors and shading to distance the "light source" from objects that he wanted to appear farther away. His shading technique allows the audience to discern the distance between objects due to their relative distances from a stationary light source that illuminates the scene. Furthermore, he uses a blue tint on objects that should be farther away and redder tint to objects in the foreground.

Full size dioramas

A diorama in the Museum of Natural History in Milan (Italy).
A diorama in the Museum of Natural History in Milan (Italy).

Modern museum dioramas may be seen in most major natural history museums. Typically, these displays use a tilted plane to represent what would otherwise be a level surface, incorporate a painted background of distant objects, and often employ false perspective, carefully modifying the scale of objects placed on the plane to reinforce the illusion through depth perception in which objects of identical real-world size placed farther from the observer appear smaller than those closer. Often the distant painted background or sky will be painted upon a continuous curved surface so that the viewer is not distracted by corners, seams, or edges. All of these techniques are means of presenting a realistic view of a large scene in a compact space. A photograph or single-eye view of such a diorama can be especially convincing since in this case there is no distraction by the binocular perception of depth.

Carl Akeley, a naturalist, sculptor, and taxidermist, is credited with creating the first ever habitat diorama in the year 1889. Akeley's diorama featured taxidermied beavers in a three-dimensional habitat with a realistic, painted background. With the support of curator Frank M. Chapman, Akeley designed the popular habitat dioramas featured at the American Museum of Natural History. Combining art with science, these exhibitions were intended to educate the public about the growing need for habitat conservation. The modern AMNH Exhibitions Lab is charged with the creation of all dioramas and otherwise immersive environments in the museum.[12]

Theme parks

Forced perspective is extensively employed at theme parks and other such architecture as found in Disneyland and Las Vegas, often to make structures seem larger than they are in reality where physically larger structures would not be feasible or desirable, or to otherwise provide an optical illusion for entertainment value. Most notably, it is used by Walt Disney Imagineering in the Disney Theme Parks. Some notable examples of forced perspective in the parks, used to make the objects bigger, are the castles (Sleeping Beauty, Cinderella, and Belle). One of the most notable examples of forced perspective being used to make the object appear smaller is The American Adventure pavilion in Epcot.

Gallery

See also

References

  1. ^ Daniela Bertol; David Foell (1997). Designing Digital Space: An Architect's Guide to Virtual Reality. John Wiley & Sons. pp. 34–. ISBN 978-0-471-14662-9.
  2. ^ Kevin Brownlow, David Lean, p.209
  3. ^ London, Bianca (27 May 2013). "'Baby mugging' photo trend arrives in the UK: Adorable tots pose in 'giant' tea cups". Daily Mail. Associated Newspapers Ltd. Retrieved 3 February 2015.
  4. ^ Adam Eisenberg (November 1989). "Ghostbusters II: Ghostbusters Revisited". Cinefex.
  5. ^ Knight, Randall Dewey., Brian Jones, and Stuart Field. College Physics: a Strategic Approach. 1st ed. San Francisco: Pearson Education, 2006. Print. p. 704-705.
  6. ^ Michael A. Seeds; Dana E. Backman (2010). Stars and Galaxies (7 ed.). Brooks Cole. p. 39.
  7. ^ O'Shea, R.P., Blackburn, S.G., & Ono, H. (1994). Contrast as a depth cue. Vision Research, 34, 1595–1604.
  8. ^ George Mather (1996) "Image Blur as a Pictorial Depth Cue". Proceedings: Biological Sciences, Vol. 263, No. 1367 (Feb. 22, 1996), pp. 169–172.
  9. ^ "Gestalt Psychology". Retrieved 5 March 2013.
  10. ^ Lipton, L. (1982) Foundations of the Stereoscopic Cinema - A Study in Depth. New York, Van Nostrand Reinhold, pg 56.
  11. ^ a b Purves D, Lotto B (2003) Why We See What We Do: An Empirical Theory of Vision. Sunderland, MA: Sinauer Associates.
  12. ^ Stephen Christopher Quinn, Windows on Nature: The Great Habitat Dioramas of the American Museum of Natural History, Abrams, New York, 2006.
  13. ^ Wright], the Imagineers ; [Alex (2007). The Imagineering Field Guide to Epcot at Walt Disney World : an Imagineer's-Eye Tour (1st ed.). New York: Disney Editions. p. 103. ISBN 0786848863.

External links

This page was last edited on 12 November 2018, at 03:39
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