When we study the development of film, it is well known that film has a long history of 100 years. But in fact, before the birth of film, people had known the mechanism of stereoscopic vision. Moreover, the display equipment and stereo class had been developed.
However, the early stereoscopic film was only played roles in the programs of science and technology hall, museum and theme park, not being popularized. The simple reason is the technology limitation.
Before the digital technology was widely used, the cost of producing and showing of stereoscopic film was much higher then ordinary film. What's more, the visual effect was unsatisfactory, easy to bring uncomfortable feelings to the audience. With the development and popularization of technology, these conditions have been much improved.
With the help of digital technology, the stereoscopic effect of film has been almost made perfect, and it is much easier to play 3D films than in the past of photographic era. The cost of 3D films has been reducing. We can conclude that 3D era is not come out accidently, but the result of technology accumulation of more than 100 years.
Nowadays with the popularization of 3D films, 3D films has begun to be selling points. Some people may think they can very easily producing a 3D films with just two machines. But the fact is that large amount of complicated post-production work was needed for an excellent 3D films, besides the quality of the literary drama.
It is almost impossible for one person to succeed in producing 3D films, if this person has never successfully produced a 2D film. Any excellent film is a result of team. In digital film era, it is more important for the cooperation of different discipline and different fields. In the team of digital film, the most important role is the inter-disciplinary talent who knows the artistic creation regular and modern technology as well.
For those who love films, James Cameron shouldn't be a stranger. He is the successful guider of 《The Terminator》, 《RMS Titanic》, 《True Lies》. Most of us may be just immersed in the story of these films, and seldom think about who has directed these wonderful films. Some careful people may know this great director through his most exciting film of 《RMS Titanic》. However, it is the 3D film of 《Avatar》 which he has spent 10 years to produce that truly made him get the highest glory in film producing field.
It is a miracle in film field for the over 2.5billion high box-office receipts of 《Avatar》. There is nobody surpass him up to now, ,maybe no one can exceed for a very long time. Maybe just James Cameron can beyond himself in the future.
The torrent of 3D films triggered by the success of 《Avatar》 triggered the, makes the businessmen worldwide aware of the enormous opportunity in the fields of 3D market, for example, the display of three-dimensional image, the appended market of three-dimensional image, data transfer of 3D image, education by 3D image, application in science and technology, medical equipment, GPS, 3D games, military usage, Simulator, 3D TV and 3D glasses. Though it brought about a very large new market and big business moment, the number of 3D images is much less than enough. For this reason, producing high quality 3D films and popularize them in the world, building a sharing system for 3D films, guaranteeing the richness of 3D films, and at the same time standardizing the playing system so as to ensure a unblocked transmitting would be needed in the future.
However nowadays what we need to do is to learn the Fabrication Methods of 3D image, to accumulate fabrication experience of 3D image through continuous study, and to communicate technology and share experience with other countries. Film is a special medium, it record, re-organize and display what happened on the screen through vision, audition, tact us. The prominent glamour of 3D film is that they can let you feel you are in the real scene. The information we obtained, 80% comes from our eyes, 15% comes from ears, and 5% comes from touch. 3D film brings you the most strong real sensation and interaction by taking advantage of the principle of vision, audition, tact us to the most.
The propose of the paper is to discuss the producing process and the business potential of 3D film through 3D Stereoscopic short film〈Come back soon again playing in the garden, Mom〉.
As mentioned by James Cameron, if we reasonably utilize and develop the 10 pieces of advice listed below, we can produce high quality 3D films.
1, There is no screen
"Whenever somebody starts talking about 'stuff coming off the screen,' ignore them," says Cameron. "They are charlatans. The brain does not think there's a screen there at all. It is fooled into thinking there is a window there; a window looking through into an alternate reality. In fact, the brain is barely aware of the boundaries of the that window or of how far away that window is, which is why objects which break the frame edges may be shot at distances closer than the actual screen plane, which classical stereography texts will tell you won't work. Not only does it work, it is essential to doing good narrative 3D that this old rule be broken as frequently as possible."
2, Stereo is very subjective
No two people process it exactly the same says Cameron. It's important to get a group consensus.
3, Analyzing stereo space on freeze frames can be misleading
You can work this way, but the final judgment needs to be done with the shots flowing, and ideally in the actual cut. Generally they look worse stopped than moving because the eye gets depth cues from motion as well as parallax. However, excessive strobing caused by the 24P display rate may actually worsen the comfort factor in some shots advises Cameron.
4, Convergence Cannot fix stereo space problems
This is critical to remember Cameron warns. Correct convergence does two things: It allows the eye to fuse quickly when cutting from one shot to another. It can also be used to reduce ghosting caused by bleed through of the glasses on high-contrast subjects in the background depth planes. The eye will fuse a given object in frame in direct proportion to how closely converged it is; more converged, faster fusion. You can only converge to one image plane at a time [and when its done] make sure it is the place the audience--or the majority of the audience--is looking.
5, Convergence is almost always set on the subject of greatest interest
This follows the operating paradigm for focus ... the eyes of the actor talking. If focus is racked during the shot to another subject, then convergence should rack. An exception to the rule of following focus exactly is a shot with a strongly spread foreground object which is not the center of interest such as in an OTS in which case a convergence-split may be used (easing the convergence forward slightly, to soften the effect). This should be combined with control of inter ocular to yield a pleasing result. Convergence splits are limited by high contrast edges at the plane of interest, which may cause ghosting in passive viewing systems.
6, Inter ocular distance varies in direct proportion to subject distance from the lens
The closer the subject, the smaller the inter ocular. The farther away the subject is, the larger the inter ocular distance. A shot of the Grand Canyon from half a mile away may have a 5-foot inter ocular. A shot of a bug from a few inches away may have a 1/4-inch inter ocular. Inter ocular tolerance is subjective, but there is a constant value of background split which cannot be exceeded.
7, Inter ocular and convergence should both vary dynamically throughout moving shots
8, a composite, the foreground and background may want to have different inter oculars
Cameron provides an example such as in an OTS, the stereo space between the two foreground characters may be compressed, and the stereo space in the background may not be compressed. Conversely, in a problematic green screen comp where the inter ocular was baked in too wide, the background may be brought closer to some extent by shifting one eye horizontally relative to the other. These fixes only work in shots with an empty mid-ground between the foreground elements and the nearest objects in the background. This technique can be used or abused.
9, When stereo looks bad to the eye it is important to eliminate the possible problems sequentially:
1), Synch: the number one killer of young eyeballs
2), Reverse Stereo: This will look equally egregious. Some shots may actually appear to almost work as stereo, but foreground objects will look "cut out" as if you are looking through a window. Turning the glasses upside down is the test. If it improves, it's reverse stereo.
3), Zoom Mismatch: Technically it's focal-length mismatch and it's characterized by a radial interference pattern when left and right images are viewed overlaid.
4), Vertical Alignment: The eye can tolerate a lot of horizontal alignment mismatch--this is equivalent to incorrect convergence-but very little vertical misalignment.
5), Color or Density Mismatch: The brain is more sensitive to density mismatch than color, but both should be matched. It's also important to note that with linear polarization there will always be a slight magenta/cyan shift between the eyes. This should NOT be corrected in the color timing of the master because some systems use circular polarization, which doesn't have this shift.
6), Render Errors or element drop-outs between eyes: Some elements, including objects, shadows or lighting artifacts are missing from one eye.
7), Specular Highlights: Because the angle of reflection is different for glossy or mirror surfaces as viewed from left or right eyes highlights may exist in one eye but not the other.
8), Lens Flare & matte box shadows: These problems typically affect one lens.
9), Image Warping: This problem can happen at the edges of frame with certain lenses and it can happen with warped beam splitters.
10), Movement or vibration which is different in left & right (L-R): This shows up in some camera systems Cameron explains. It takes a lot of jiggle between eyes to become apparent. Only when all these possible sources of brain-shear (Cameron's term for bad stereoscopic content) have been eliminated, should inter ocular be re-examined he adds.
10, Some shots just can't be fixed
If they are photographic shots with the inter ocular baked in they must be re-done or they must be left in the film as non-stereo shots (L-L). If they are CG [computer-generated] shots, the inter ocular can be reduced to a very low value to give a sense of some stereo space even though it is inconsistent with the rest of the sequence. Cameron notes that in the dramatic flow of the film the low value will work.
After we thoroughly understand the 10 pieces of advice, study the mechanism of 3D stereoscopic image, displaying methods, transmitting ways, and compare the whole producing process of 3D and 2D films, we can obtain the essentials of 3D film producing and accumulate experience and make continuous progress. Co-operation in team members is very important for producing successful 3D films. The following work after making a 3D film propagation and development of additional value. One point we should always remember is that the showing of 3D film is only one part of 3D film. We should make full use of 3D technology to develop related programs such as 3D games, 3D drama, 3D advertisement etc.
3D film should be the tendency and will be popular in the future. I believe that the forthcoming market of film is the world of 3D film through our endeavor.