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How a 3-D movie is made –
from Home to Hollywood 3-D
A step-by-step guide that will take you
from 3-D Script to 3-D Screen
Before you start filming in 3-D
A script should be written with 3-D in mind. There are three axes to work
with so action can take place horizontally, vertically, into the screen
and out of the screen. While it may be the task of the storyboard(er)
to visualise the story in 3-Dimensional mise-en-scene, the script should
allow room for this movement. Plot twists, character actions and object
importance can be emphasized by using placement into the available depth.
Camera moves become a different tool and using cinematic language like
choice of lens, light, cuts and transitions changes dramatically in a
3-D film.
Ideally, you will need a subject and a story that will look better in
3-D than in 2-D. A story that translates a unique emotion because of its
3-Dimensionality. One could theorise about what the third dimension means
for the language of film - and at The 3-D Revolution we do just that. Check
out the pages on stereoscopic cinematography and the reasons for filming
in 3-D.
Still from Friday the 13th - Part III - 3-D
In 3-D, we are literally closer to this helpless victim of Jason Voorhees.
The horror envelops us -
but does the visual spectacle take us out of the
cinematic experience or enhance it?
A 3-D Camera
Clearly, you will need a camera of some sorts to film your subject in
3-D. A DV camera or a regular camcorder
or a film camera on its own is not enough. Please note that shooting 3-D
is totally separate from presenting 3-D because you can treat any source
material in post production to meet your presentation needs.
You will either need a Second camera or a 3-D Lens adapter.
As you may have figured out, to produce quality like you see in an IMAX
theatre or in a release like Spy Kids 3-D, you need a film or HD video
camera with sufficient resolution to fill a huge theatre screen. In
brief, and generically speaking, 3-D IMAX works with a resolution of about
3840 x 2880 pixels, a 3-D HD camera can have a resolution of 1920 x 1080,
while a 3-D consumer DV camera works with 720 x 480 pixels. You can see
that blowing up DV to IMAX would be quite a painful visual experience.
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To rule out any confusion:
DV is Digital Video - the consumer video standard
that has replaced VHS and S-VHS.
HD is High Definition
- a new professional video format trying to replace 35MM and 65MM
film.
DLP (Digital Line Projection) or D-Cinema (Digital Cinema) is a way of projecting high definition video (not
neccecarily HD) on a cinema screen.
This is not DVD (Digital Versitile Disc)
- the consumer video standard that has replaced VHS.
Although the words 'resolution' and 'pixels' are
used here, film like IMAX or 35MM does not have any pixels because
it is an optical medium that works on atomic level. However, experts
have agreed on a pixel resolution of film so that it can be compared
numerically to video.
Blowing up HD to IMAX resolution (DMR) can
produce grainy artefacts that will damage 3-D. To read more about
this, check out the 21st
Century 3-D section. |
Alternative techiques
There are two other techniques that allow for shooting with one
camera and no camera attachment. These are the Pulfrich method and the ChromaDepth method and they are totally
unrelated to any 3-D camera setup.
Pulfrich only works when the camera
and / or the objects around it are spinning (moving horizontally), so
your choice of subject matter is rather limited. Objects moving from right
to left in relation to other objects will appear to be in front of those
other objects. Objects moving from left to right in relationship to other
objects will appear to be behind those other objects.
This technique works with all forms of presentation and all storing formats.
Your audience will have to wear glasses with one clear (left eye) and
one darkened (right eye) glass.
Chromadepth requires coloured lights from red, via orange, yellow, green to blue
to light your scene. All red objects will stick out of the screen
and the other colours go further into the screen. Blue objects are
in the back.
This technique works with all forms of presentation and all storing
formats. Your audience will have to wear Chromadepth glasses.
Click here to see an example of a Chromadepth movie |
ChromaDepth 3D Rendering of a Teapot |
3-D Setup with a second
camera

Two identical DV cameras on a slidebar by John Billingham |
Ideally, the two cameras are of the same
make. This, to minimize differences in image quality, look, feel and
frame rate. For example: a DV camera and a film camera won’t
be a workable setup because video records at 25 frames per second
(25 fps) and film records at 24 fps. Also, a lot of DV cameras can
film in progressive mode instead of interlaced mode, at which regular
camcorders will always record. So watch out for progressive/interlaced
settings on your DV cameras. |
Interlaced vs. Progressive
In the case of PAL video, recording interlaced means recording an
image every 50th of a second, but storing those images on the even
lines of video and storing the 2nd 50th of a second on the odd lines
of video. These images are then called fields in stead of frames,
so while video runs at 25 fames per second, every frame consists or
2 fields and thus video runs at 50 fields per second. Why? It makes
for smoother motion and the human eye is too lazy or too indifferent
to see the difference between 576 lines or image and 288 lines of
image.
Shooting progressive means forgetting about the interlaced technique
and just recording the whole frame at 25 fps, using the full 576 lines.
This gives a filmic look to your video because that’s what happens
in film (which records a whole frame at 24 fps), but fast motion will
appear to strobe because of the reduced frequency.
For NTSC, the story is the same, but the fps is 29.97 and the field
frequency will thus be 60 fields per second. NTSC has a height of
480 lines, so 240 lines will be used in interlaced mode. |

Two identical video cameras on a slidebar by John Billingham |
Camera and lens distance
In the case of two cameras, they need to be fixed next to each other
on a bar that you (or your cameraman) can hold and / or fits onto
a tripod or even a Steadicam.
So how far do the lenses of your cameras need to be apart? Well, this
depends on the contents of your scene and desired 3-D depth perception,
but as a good starting point and in most occasions the distance should
that 65 mm or 2.5 inches. This
is the distance between your eyes, so the cameras see the world the
way you see it. And changing this distance means manipulating the
way your audience sees your scene in 3-D.
This distance is called interaxial or interocular distance in 3-D filmmaking terms.
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3-D legend Daniel Symmes holding a camera
with his 3-D lens adapter - on a Steadicam
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Typical example of cardboarding. In this case, the
creator of these images was trying to generate
3-D pictures that look good both with and without 3-D glasses. But
something's gotta give. |

Most lenses, placed next to each other, will create
a larger than natural interaxial of approximately 70-75 mm |
So what happens when you change this interaxial value? In short, when
you make the interaxial smaller, the 3-D image will look flatter. At a
certain point, objects will look so flat, they’ll look like cardboard
cut-outs. Hence the term ‘cardboarding’ is used. Inversely,
when you increase the interaxial, the 3-D image will look smaller in proportion.
At a certain point, objects will look like they are miniatures, or the
audience feels like a giant. This is called hyper-stereoscopy.
Murray Lerner setting up a hyper-stereoscopic shot for 'Magic
Journeys' |

Dual small HD Cameras on a slidebar |
What if your cameras are too bulky to have their lenses next to each
other at a distance of 65 mm? A setup with mirrors or a special
rig will have to do the trick. You can use a simple setup with cameras
facing each other, filming off 45-degree mirrors or you can use any other
creative mirror solution.

Warner's NaturalVision camera used on House of Wax
Simple 45 Degree mirror 3-D filming |

Double 45 degree mirrors creating a larger interaxial |

Paracam 3-D camera rig |
Shooting
forward or converging
Now you can choose to point your cameras (or mirrors) straight forward
or make them toe-in. On 3-D lens adapters you can use control knobs
for this. If you don’t fix the cameras to your rig, but attach
them with rotating parts, you can control the shooting angle between
shots or even whilst shooting!
Shooting straight forward results in the better, calmer 3-D shots but
more work needs to be done in post to get the parts of the shot out of
the screen and inside of the screen as needed. Part of this work will
require Stereo Base shifting, which will result in cropped imagery.
Therefore, parallel-shot 3-D is always shot with excess space on the
sides.
The work in post to shift parallel footage
in depth is not necessarily more work that needs to be done on
converging camera shots. Because converged material may well need image
distortion correction to counteract keystone distrotion - in other
words: keystone correction. Every 3-D shot will need post-productional
review as shots may need to be set back or come forward more, have
image distortion correction applied and be scaled or clipped on the
sides to prevent retinal rivalry.
For more information on getting post work done on your 3-D imagery, contact 3-D Revolution Productions.
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Moonridge 5 3-D still: Parallel cameras used
Stereo Base correction applied in post |

Same shot, different setup: Converging cameras used
Keystone correction applied in post |
Converging cameras
Toeing-in means crossing the
cameras’ view paths and it can result in both spectacular and plain bad 3-D results. The easy thing to understand about convergence is that any object in front of the point
where the cameras’ viewpoints cross, or converge, will stick
out of the screen when viewed in 3-D.
This out-of-screen, or 'negative screen parallax', also enhances the stereoscopic effect
of your scene because of the exaggerated difference between the left-eye
and right-eye angle on objects in your scene.
However, when using converging cameras, the depth of your scene can
only be limited. Because the cameras’ view paths are crossed,
so will the eyes of the audience be and any points on the horizon
can be further apart than the eyes can turns outwards. This outward
turning of the eyes is called divergence and generally speaking 3-D
experts agree that 1 degree of divergence is acceptable but best to
be avoided if possible. Needless to say, this creates discomfort with
the audience and any available popcorn may be expected to be hitting
the screen in abundance.

Second of all, toeing-in generates distortion
of the combined 3-D image. This distortion is called keystoning and
it is equal to a vertical skewing in opposite ways for left- and right
eye images. This then results in vertical parallax – 3-D’s
biggest enemy. It means having an image or image points that are vertically
displaced in comparison to the other eye’s image. Since the
muscles around your eyes can’t normally do this (one eye looking
up, the other down), eyestrain occurs with your audience. Some of
this distortion can be corrected in post-production.
Contrary
to popular belief, modern technology cannot fix this problem. Even the
most expensive and most advanced rig in the world will face the same
problems when crossing the cameras' paths. One cannot bend the laws of
physics...

Shot in CGI with two converging cameras,
this title shot shows non-disruptive keystoning |

With a close up of the upper-corners the vertical parallax
resulting from the keystone distortion is clearly visible |

Converging or toeing-in
Browsing the image forces the eyes to go
from converging (near) to diverging (far) |

Parallel or Straight-forward
Browsing through the image
keeps the eyes converged (near and far) |
All these bad side effects can be avoided by employing a stereographer
who knows his 3-D. A lot of stereographers use formulae to determine
what's the best 3-D setup to be used for particular shots. Hollywood of
the 1953-D boom even came up with a spy-on-the-fly 3-D camera value
disc (see illustration below). As every 3-D shot requires a different creative
approach, simply and only relying on 3-D calculators may not be the
best practise. Such a table of values can prevent eyestrain, but it
can't prevent bad 3-D movies from being made. 3-D shots need to be
thought through from every angle, which is something that a
stereographer can help you do.

StereoVision lens converging on wild man with spear
for
The Surfer Girls (a.k.a. Fantasy in Hawaii)
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Motion Picture Research council 3-D calculator
Used from 1953 onwards |
Filming in 3-Dimensions
When planning for a 3-D scene it is important to realize that we as humans
perceive the 3-Dness world not just because we have two eyes. Things like
depth cues, texture, light and shadow and even sound levels tell our brain
a lot about our distance to objects around us. Use these elements to create
powerful 3-D, or choose to confuse your audience by leaving these elements
away. They are important tools of the 3-D filmmaker, besides the equally
important camera variables of aperture size, focal length, depth of field, use or absence
of colour, and all other tools available to filmmakers.
There are also some basic filming tips to stick to so that your audience
will have a pleasant 3-D viewing experience. Of course you may want to
discomfort your audience on purpose, but some things just don’t
work in 3-D cinema.
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Convergence, interaxial distance, horopter limitation...
Stereoscopic 3-D is intrinsically complicated
and far from a point-and-shoot medium. If you are looking to have all
this 3-D information applied to your 3-D production, and you simply
don't have the budget and time to investigate it all for yourself, why
not contact 3-D Revolution Productions and get your 3-D project sorted quickly, easily and professionally.
Contact 3-D Revolution Productions
Tel +44 1179 441 449
For 3-D without the headaches
|
Camera moves
A very fast moving camera results in 3-D that cannot be taken in properly.
A violently shaking camera results in impossible to see 3-D. Eyes observing
3-D need more time than they need for 2-D shots. However, this is all but true
for the object the viewer is focussing on. When the viewer is
trying to focus on a spinning background, it’s not going to work
and he will close his eyes. But when there is an actor of object standing
or floating still before that spinning background your audience has a
good point of focus and you can pull off such a shot. This also goes for
horizontal driving shots; the audience will have the furthest planes of
background to focus on.
Otherwise, keep it slow and don’t throw stuff at the camera. Oh,
alright then, if you must… just remember what André de Toth, director
of House of Wax said: “It’s not to throw things at you but
to involve the audience... In stead of showing the story to an audience,
make them part of it; the feeling, the experience.” And Rupert Hitzig,
producer of Jaws 3-D: “If an off-screen effect serves to stop the
action and remind viewers they’re at a movie and not watching a
real-life story unfold, it fails”.
André de Toth - wearing his eye-patch - with
3-D professionals Dan Symmes, John Astin and
Chuck Henry. Not being able to see the 3-D effect
for himself still made de Toth a better
stereographer than any of the ones that did. |

Rupert Hitzig may have had a point, but in practice
Jaws 3-D features
plenty of these off-the-screen shots of objects resulting from a rampaging
shark. |
Frame boundaries
If vertical parallax is 3-D’s biggest enemy, objects that are cut
off by the frame edge are its second biggest nemesis. In order for the
eyes to combine the left eye and the right eye image, the objects in both
those images must not be cut off by the edge of the frame. Otherwise,
retinal rivalry will occur and again this equals eyestrain.
Right, but
every image has such cut-off objects; it is an unavoidable fact of photography.
So the best thing to do is to make sure any object your shot is focussing
on is never cut off. As long as the audience is looking at one object,
they will not diverge their eyes to background objects that may be causing
eyestrain because of retinal rivalry. At least, that’s what you
aim for.
The most memorable shots in 3-D cinema are the ones that contain out-of-the-screen
objects. But there is a tricky bit about these objects. As you just read,
objects should not be cut off by the edge of the frame. Especially when
they are the objects of attention. So you have to somehow stick something
out of the screen, close to the camera and thus close to the audience,
but keep it small enough so that it stays within the frame boundaries.
As you may be figuring out, making a car drive out of the screen and come
to a rubber-burning halt to within an inch of your audience is not going
to work unless you are using a mini model car. So you will find yourself
restricted to using objects like hands, balls, poles, ladders, flying
killer robots, and small fluffy aliens.
Contrast
High contrast should be avoided. Pure blacks cannot be distinguished in 3-D and pure
whites create ghosting. So night scenes are bad for 3-D (unless well
lit). Equally bad are bright lights. Both destroy the 3-D effect.
No matter how good your method of projection is, there will always be
some crosstalk (double images) of left eye and right eye images. Sometimes
it is simply the brain failing to completely combine stereoscopic images;
sometimes it is actually the less than perfect quality of the 3-D glasses,
silver screen or colour representation of a projector. Besides these factors,
the extra-stereoscopic depth cues are still a very important factor in
successful 3-D. Keep even the darkest scenes well lit so depth and object
position can actually be distinguished. The more objects visible in space
and the more texture, the more depth.

Still of Amityville 3-D: too dark and that flashlight is another really bad idea for 3-D
Depth of Field
Most 3-D photographers and filmmakers proclaim that the full depth of
field should be in focus with 3-D. This, they argue, because the audience’s
eyes scan the image and should be able to examine all the objects within
the image in all its sharpness and detail – just like in real life.
But this is not what happens in real life. When you hold a finger close
to your eyes and focus on the room around you, your finger will be out
of focus. When you focus on your finger, the surrounding room goes out
of focus. Just like we sometimes see happening in film. And so in 3-D
cinematography having a limited depth of field should not be in any way
prohibiting.
The same goes for using zoom, but in 3-D using zoom also means decreasing
the interaxial distance when toeing-in is employed. And this will decrease
the depth of the scene.
Moonridge 5 shot in 3-D with full Depth of Field.
No need to discard one of cinematography's biggest visual impacts.
Particular to a 3-D video lens adapter
A drawback of filming with a field-sequential lens adapter occurs with
any motion in the scenery or camera motion. Because the two fields representing
left eye and right eye images are not recorded at the same time but sequentially,
so after each other, a 1/50th (PAL) or 1/60th (NTSC) of a second lag occurs
between these two images. This can seriously reduce the stereoscopic value
of the image or even cause eyestrain. So this goes when horizontal or
vertical movement is filmed or a camera pan or tilt is employed.
Editing & Post production
Although for the editing process on its own
you can choose any available and workable 3-D display technique, the final
edit will have to be post processed to produce a form of image separation.
Please note that shooting 3-D is totally separate from presenting 3-D
because you can treat any source material in post production to meet your
presentation needs.
As with filming 3-D, editing 3-D has some practical limitations –
or should we say guidelines.
Because the eyes of the audience will ‘scan’ every new 3-D
shot, they need a little bit more time per shot. However, shots should
not last for too long otherwise the eyes of the audience will start wandering
off into the depth of the scene, analyzing the 3-D shot. That will take
them out of the movie, so a certain limit should be applied unless you
want the audience to do this – when there is just atmosphere and
no protagonist on screen for example.
Another good idea is to use slow(er) fades. Again, this gives the audience
a chance to adapt to the new scene’s depth.
One should most definitely be careful with cutting between different camera setups; close-ups
and wide shots will be of different interaxials and convergence values.
So to give the eyes a chance to adjust to these differences where an in-between
cut of a medium close-up could be used between a wide shot and a close-up.
Altenatively, when convergence points are matched from shot to shot, faster edits can be achieved.
Projecting 3-D Film or Video
The biggest budgetary choices are made with the projection part of your
3-D production.
A short line-up can be made of the choices, from cheapest to most expensive;
the required extras, equalling extra costs, are written underneath the
options:
Pulfrich
projection - click to watch example movie
Pulfrich
glasses
ChromaDepth
projection - click to watch example movie
ChromaDepth
glasses
Anaglyphic/Anaglyph,
ColorCode or Trioviz projection from one source
Anaglyphic
or ColorCode glasses – the latter being more expensive with an equal
effect
Anaglyphic/Anaglyph,
ColorCode or Trioviz projection from one source with beamsplitter
Anaglyphic
or ColorCode glasses and beamsplitter
Anaglyphic/Anaglyph,
ColorCode or Trioviz projection from two sources
Anaglyphic
or ColorCode glasses, red & blue / red&green+blue / yellow&blue
colour filters, two projectors, two reels or videos and interlocking mechanism
Polarised
projection from one source with beamsplitter
Polarised
glasses (linear or circular), beamsplitter, polarising beamsplitter lenses,
silver screen
Polarised
projection from two sources: Small venue, IMAX
Polarised
glasses, two projectors, two reels or videos and interlocking mechanism,
polarising projector lenses, silver screen
Polarised
projection from DLP source with Real-D projection
Polarised
glasses (linear or circular), digital frame server, digital projector, polarizing Real-D adapter, silver screen
Colour wavelength separation with Dolby 3-D projection
Dolby 3-D colour wavelength
glasses, double speed film / double speed video or HD / field sequential
video, sequential wavelength separating Dolby 3-D adapter,
regular screen
Sequential
shutter projection (active): Xpand, IMAX
Electronic
shutter glasses, double speed film / double speed video or HD / field
sequential video, synchronised projection shutter, infrared emitter
Ivanov
Free view (glassless) projection
Two
screen-size rasters of thin panels, two synchronised projectors, translucent
screen
Lenticular
or Fresnel Lens system
Lenticular
or Fresnel plastic or glass slab
Anaglyphic/Anaglyph projection
The most famous form of presented 3-D is the red & blue 3-D. However,
this is also one of the least common forms of theatrical presentation
because its limitations in quality.
In print, however, it is the most common form of 3-D presentation.
The premise of anaglyphic (or anaglyph) stereoscopics is separation of the images through
a red image for the left eye and a blue image for the right eye, overlapping
on the screen (a grey, purple or yellowish image with red and blue edges
resulting). This means the film is going to be perceived as purplish grey
by the viewer.
Full colour images are not entirely possible. There is a way of using
a ‘regularly’ coloured image, with an added 3D effect for
viewers who wear anaglyphic glasses.

Anaglyphic still from Spy Kids 3-D using Red, Green
and Blue
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The same still using just Red and Cyan
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Take
the cinematic 3-D release of 'Journey to the Center of the Earth': the
choice for murky, muted colours has been the same as for what was seen
in Sharkboy & Lavagirl: the anaglyph DVD release is to
work well colour-wise and not have conflicting colours that produce
ghosting with the anaglyphs. So that means no red and no blues or
cyans, while oranges and greens are sort-of OK but not really super,
leaving browns, pinks and purples besides whites, blacks and greys.
This is a bit of a technical story, but it certainly needen't be like
this. Using the right colour correction for the anaglyph encoding, 3-D
film production can use all colours it wants without restraint,
resulting in a gorgeous colour-bursting Real-D (and possibly IMAX 3-D)
experience and an equally colour-true anaglyph experience - without the
ghosting associated with the use of reds and blues.

Original Stereo Pair image from Wikimedia, anaglyph created by 3-D Revolution Productions - Original Image from this link
The
trick with the whole process is that viewers are not going to watch the
3-D version of the film without anaglyph glasses on, so they only care
about what the movie looks like through their 3-D glasses. The 2D
version can then have all the correct colours you like. There is,
practically speaking, no reason to keep all colours intact for an
anaglyph 3-D version of a film. What matters is the viewer's experience
and the quality of the 3-D plus colour correctness plays a very
important part in that. Anaglyph colour correction results in the best
possible end results for both these factors.
If you are a producer or director engaged in a 3-D film production, don't hesitate to contact 3-D Revolution Productions to learn about this anaglyph colour correction. It's time to shoot your 3-D project in all the colours you imagined! Contact us: 

2D still from Spy Kids 3-D - lush colours, but a potential nightmare for anaglyphs.
No longer so with anaglyph colour correction
Black & White anaglyphs
The lack of colour in anaglyphic 3-D doesn't have to be a problem
when your 3-D film is black & white anyway - like a 50ties style
movie, a movie focussing more on content, or an art film of some sort.
Use the look as a strength of your film.
Frustratingly, anaglyphic encoding doesn’t work well with video and TV since
its YCbCr colour space is very limited. This includes 4:2:2 DLP projection
but excludes 4:4:4 DLP projection. More
about this in the 3-D TV section.
The anaglyphic option works without issues for theatre and with computer monitors.
This is due to the ability of film and RGB monitors to keep colours intact
and correctly separated. |

Converted 3-D still from The Bride of Frankenstein |
ColorCode
ColorCode is a patented spin-off of anaglyphics, using yellow and blue to separate
the left eye and right eye image. RGB channel wise, yellow is red plus
green. The resulting image is in colour in the same way semi-anaglyphics
uses all of the RGB colours. The presentation limitations of this system
are pretty much the same as anaglyphics.
Still from 3-D Mania in ColorCode |

Still from Dial M for Murder in ColorCode |
Polarised projection
Polarised projection is quite simply the best way to present 3-D stereoscopic
imagery.
It enables full colour, full frame, full frame rate 3-D with an audience
wearing lightweight, unobtrusive polarised glasses.
This technique works through the premise of polarisation of light, so
it can only be used with projection rather than with a single television
or computer screen.
Polarising the projected light means allowing only horizontal or vertical
light waves to hit the silver screen. Silver, because a normal screen
does not bounce all the light to the audience and that would mean a lot
of the polarisation getting lost.
The horizontally travelling light waves are then allowed into one eye
but not the other by rotating the polarising filter in the glasses 90
degrees. This means that one glass only allows horizontal light wave to
get through and the other glass only allows vertical light waves to get
through.
How Polarizing light and polarised image selection works
So you can use either one of two projector setups. The first has two projectors:
one has a lens with a polarising filter in the horizontal position and
the other projector has a lens with a polarising filter in the vertical
position. The second setup has on projector with a beamsplitter, projecting
over-and-under, side-by-side or frame-sequential 3-D, directing the images through a beamsplitter
fitter with polarising filters.
Besides the need for a silver screen, the screen should also be tilted
forward slightly to allow the light to bounce straight into the eyes of
the audience. Opposite to the gun-ho approach of anaglyphic projection,
polarised projection is quite dependent on precise configuration of prime
quality materials and a projector’s eye for detail.
The 3-D Glasses themselves
3D glasses come in different quality and prices. As with the different
systems, the better the quality, the more expensive the goods.
Limited-time projections like festivals will include the cheap cardboard
glasses with plastic filters, whereas a permanent show like in a theme
park will invest in hard plastic glasses with hard plastic or semi-glass
filters.
A very important factor in this budgetary consideration is the issue of
ghosting; when using cheap glasses (of poor quality), separation of the
left and right image is not going to work as well as with decent glasses.
Hence, the left eye will see some of the image meant for the right eye,
and the right eye will see some of the image meant for the left eye. This
is exactly what should never happen with 3-D.
Also, bad filtering means a failing of objects that come out of the screen
in very close proximity to the viewer. The viewer's eyes will lose focus,
the brain won't combine the two images anymore and two separate images
will appear in front of the viewer.
Contact The 3-D Revolution for your selection of 3-D glasses
Freeview (glassless) projection
Freeview (free view) 3-D systems, or 'glassless' 3-D systems, are generally speaking
not very practical or realistic systems for mass display. They are normally
found at advertising spaces, trade shows, theme parks and other exhibition
spaces with limited viewpoints. Because these systems work with lenses
and their redirection of image parts to the different eyes of the viewer,
normally only one to five people can see these freeview 3-D images at
the same time. Where there is one perfect (or sweet-) spot that allows
for undisturbed 3-D viewing.
Ivanov 3-D Screen
As early as 1940 the Russians had already devised an autostereoscopic
system that has been mostly forgotten about. D.V. Surenskii and S.P.
Ivanov created an ingenious system for Soyuzdetfilm, using two film
projectors, a translucent cinema screen and a raster of fine panels in
front of that screen - both on the side of the projectors as on the
side of the audience, to make people see 3-D without glasses in a
theatre.
The principle of this system is that the beams of light
projected from the two projectors are either blocked or let though
by the narrow gaps between the raster panels. The positions of the
projectors and the subsequent angle of the projected image makes for
the partitioning of the left eye and right eye image on the screen.
The exact same thing happens with the viewer's eyes looking at the
raster blocking the back-projected screen. The left eye will only
see the strips of imagery that reached the screen through the raster
from the left projector and the right eye will only see the imagery
from the right projector.
The only drawback, and the historic downfall of this system is the
very limited possibility of positioning of audience – a thin
strip of a few seats.
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Explanation of the communist Ivanov freeview system
using ultimate capitalist camera fodder:
The tiltle sequence for Metalstorm - The Destruction of Jared Syn |
Lenticular freeview

Explanation of the lenticular system
by Boris Starosta |
The mother of all freeview systems is
the lenticular solution.
It uses a 3-D image that has left and right eye image partitioned
into thin vertical strips onto the back of a print or screen that
has a plastic or glass layer on the viewer's side. This layer consists
of semi-spherical lenses that are at least half the number of the
vertical strips of image projected, left and right next to each other
per lens. This way, the viewer's left eye will only see the part of
the lenses that lets through the left eye image and the right eye
only sees the right eye image part.
A raster of vertical lens strips sits over an image, which is split
into strips of left-eye and right-eye views - just like the Ivanov
system. However, because of the lenses the left-eye and right-eye
strips of the image reach the correct eye without need of a raster
screen. The lenses refract, or bend, direct, the images to the correct
eye.
This system can also be used for still print. Like specialty
postcards, big merchandising property lunch boxes, trading cards and
blockbuster advertising posters. |
Fresnel freeview
Another system, popping up its re-releasing head time and again, is one
that uses a fresnel lens where the television screen or computer monitor
would normally be to direct the light from the relevant two projectors
into the left eye and right eye. As figures, the angle of seating will
be very limited with this system. The difference between lenticular and
fresnel is mainly the fact that fresnel lenslets exist both horizontally
and verticallt across the screen, while lenticualr lenses only feature
in vertical strips across the screen.

This system is also detailed
in the 3-D TV section.
The concept of Fresnel lenslets
A whole screen would consist of hundreds of these lenslets |

Kodak's fresnel HD system
Basically not freeview at all |
Besides a limited angle of possible seating of audience, the practise
of putting up a lenticular or fresnel slab of plastic or glass on a cinema
screen would be quite prohibitive.
For television or computer screen both these systems can be quite effective,
though. However, as figures, the resolution of any screen using this method
is easily divided by four; the minimum number of lenses on a camera built
for lenticular photography.
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Other systems
There are a lot of other free view 3-D systems that are not
suitable for mass audience presentation. These include concave and
bent mirror applications, hollow screens, Viewmaster-type, cross-eyed
viewing, SIRDS (Magic Eye or StereoGram), Pepper's Ghost (A.K.A.
Holavision) and VisiDep (WobbleVision).
Then there are possible future systems like dry ice, holographics,
electron beams and impractical freeview applications like the stereoptiplexer
that will not be a consumer reality in the foreseeable future.
Therefore these systems will not be discussed here. |
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Tel +44 1179 441 449
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