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Now you you
can shoot real
3D
3D
MOVIES
MOVIES
with your own
camcorder!
Last month, we introduced the subject of 3D TV and
checked out the liquid crystal shutter (LCS) spectacles
you need to view 3D in your own home. This month,
we check out a clever accessory which enables you to
shoot 3D movies with your own camcorder!
by Barrie Smith
12 Silicon Chip
www.siliconchip.com.au
I
n technology terms, we are constantly reminded that Australians
are a nation of early adopters.
Decades back we fell over ourselves
to acquire VCRs when they became
available; same with CD players; then
it was video camcorders. Today the
‘hot’ items are DVD players.
But virtually all of these are standalone purchases: once you’ve bought
the CD unit, VCR, etc, you can’t deck
them out with too many add-ons.
This was the case with the video
camcorder – until the Japanese majors
introduced the Mini DV format. Then
all hell broke loose as the computer
interests (both hardware and software)
delivered post-production solutions
so Mum, Dad and the kids could edit
their home videos into passably viewable shape.
But nothing much has been added
to the camera end of the equation . .
. until now! Now there is a relatively
simple method of shooting 3D TV for
home use.
3D fanatic
As part of my scrabble through Sydney company Mindflux’s warehouse
to prepare last month’s article, I came
upon a device that fits to almost any
home video camcorder (analog or digital) and converts it to a stereoscopic
capture device.
At this point I should declare that
I am a 3D nut. I own a bundle of
working stereo still cameras, ranging
from early 20th century wood, leather
and brass gems right up to 50s 35mm
stereo snappers, as exemplified in the
Stereo-Realist and its ilk.
And there was the time, in a moment
of madness, I happened to be in the
USA in the early 80s when the Nimslo 4-lens 35mm stereo camera was
fresh on the market: I bought one and
was soon able to enjoy the lenticular
‘happy snap’ prints this system could
produce.
So you could say I’m well and truly
binocularly-bewitched and a sucker
for anything that can capture the world
in real 3D.
An early adopter of a Stereo-Realist
camera, Dwight D (later to become
President) Eisenhower.
each eye in some scenes. But I quickly
realised I would have to hide this
‘hot’ tape from the littlies who reside
in my home and maybe take a more
leisurely peek later.
Then on to the Nu-View. Thanks
to Canon Australia I managed to
borrow one of their top new Mini DV
cam-corders, the excellent MVX1i
model with a 10X optical zoom lens.
This I used for all the tests with the
Nu-View unit.
The adaptor box was opened, the
gear taken out, setup instructions read
and the device fitted onto the camera.
Taking a brave step, I shot a quick test
of the family around the house, the
front verandah, the cars across the
street. Then, preview time.
The camera’s output was hooked
into the TV’s composite video input
least, for what is ostensibly a
consumer product.
I had already spent some
time with a few 3D VHS tapes,
a signal decoder and a pair of
LCS (Liquid Crystal Shutter)
spectacles and so I had a handle
on the stereo video experience.
The first tape I ran at home
was entitled Camp Blood, so I
naturally thought it was a horror
movie with maybe a bit of ‘in
A 1980s attempt to get
your face’ 3D action . . . rememstereo going, the 35mm Nimslo.
ber these are stereo pictures!
But in previewing it, I rapidly
discovered it was an R-rated soft porn
and the decoder was plugged into the
production with an amply endowed TV’s composite video output; the latter
young lady thrusting her stereo pair
would emit the sync pulses for the LCS
into the camera. This was in your
spectacles to do their stuff.
face, all right – with one D-cup for
Don glasses and then replay the
Nu-View 3D adaptor
As Mindflux’s Mark Giles handed
over the loaner Nu-View 3D adaptor
kit to me, there was a slightly odd look
on his face. He obviously suspected I
had no sense of what I was in for. And
he was right.
The gear is impressive to say the
www.siliconchip.com.au
Quite a handful: a Canon camcorder and a Nu-View adaptor.
November 2002 13
The Nu-View adaptor. Note the two LCS panels, which are actually mounted at 90 degrees to each other but in this shot,
the mirror at left makes them appear to be side-by-side.
tape. And up she came: a series of
full colour, live action scenes in three
dimensions on the home TV set. I have
to admit I was stunned. It was so easy:
just shoot – and play.
Principle of operation
The exciting thing about this answer to replicating the three dimensional experience is that it is one of
the rare systems that have appeared
in the 150 year or so history of stereoscopic image making that uses only
one lens and one length of recording
media.
Stereo Realist cameras, the
View-Master viewers, even the IMAX
3D cinema process rely on a pair of
taking and viewing lenses and separate
film frames; IMAX 3D of course relies
on a hefty paired camera unit and big,
linked 70mm projectors.
The Nu-View is an electro-optical
device that attaches to the front of
almost any consumer camcorder to allow the easy recording of stereoscopic
3D video.
It relies on the interlaced field that
is basic to the television system. The
two fields of 312.5 lines each are
recorded to create a single 625 line
frame. The field rate is 50Hz (in PAL),
the frame rate is 25 frames per second
(fps), so in this 3D video plan, each
alternate field is used to record/replay
14 Silicon Chip
a left-right-left-right sequence of 3D
views to create 25 fps of stereoscopic
action.
This scheme is called “Field-sequential 3D” as noted in last month’s
article.
The camera, with the Nu-View
device attached, records 25 left and
25 right eye views onto the Mini DV
tape. Replay the tape, with unaided
viewing, and you see a double image.
Slip on the LCS spectacles and you
see full-depth stereo 3D.
The Nu-View apparatus is well
conceived and extremely well executed. The
components include the
shooting adaptor itself
and a link arm assembly
that fixes the adaptor to
the camera, attaching at
one end to the camera’s
tripod thread, with the
other end connecting to
a threaded rod screwed
into the adaptor’s base.
There is also a cable
which connects the camera’s composite video
output to the adaptor’s
video input, an Allen
key, a bayonet ring
and stepping rings
which fix the adaptor’s shooting port to
the cameras’ filter thread, a soft cover
for the adaptor and one alkaline AAA
battery.
Some notes on the setup
•
The composite video connection
between the device and the camera’s
video output is essential in order to
provide field sync pulses to fire the
adaptor’s integral liquid crystal shutters (more of this later).
The adaptor’s shooting port
(through which the taking lens views)
connects to the camera’s filter thread
and stepping rings are provided to fit
37mm, 43mm, 49mm and 52mm
camera filter thread sizes.
Step-up and step-down
•
Setting up the Nu-View adaptor.
www.siliconchip.com.au
Display Systems
The Nu-View is now marketed
by Display Systems’ 3D and was
acquired from the original manufacturer, 3D Video. The device is
manufactured in the USA by ‘i-O
Display Systems’.
Aside from the Nu-View, this
Sacramento, California company
(www.i-glasses.com) manufactures personal display devices and
other stereoscopic 3D products
used in a broad array of applications
from company entertainment to
medical and commercial uses.
It is regarded as the world’s
leading manufacturer and supplier
of head mounted personal display
devices.
Looking at the “business end” of the Nu-View 3D converter, here attached to
a standard Canon MVX1i Mini DV Camcorder.
rings can be bought locally to fit other
sizes.
An Allen key is provided so that
you can adjust the vertical alignment
of the mirror, otherwise your stereo
pair will suffer from unwanted vertical
parallax.
The adaptor works with analog
and digital camcorders, NTSC or PAL.
You can copy and edit any 3D
video shot with the adaptor.
The adaptor does not work with
film movie cameras nor early tube
video cameras.
•
•
•
•
adaptor is simply a shooting port
through which the video camera
shoots anything it is pointed at. The
zoom still works as normal, although
some cameras with very wide entry
apertures (larger than 52mm) may
experience cut off corners from the
adaptor.
Auto focus works as normal, as do
the auto exposure and white balance
functions. One negative: I noticed
when the zoom was pushed to its
maximum that definition fell off markedly – a product of the clutter (Liquid
Crystal Shutters, mirrors, etc) in front
The scheme
of the lens!
The adaptor is roughly triangular in
In simple terms,
shape. Behind its curved front winthe Nu-View
dow can be seen a pair of LCS panels,
mounted at 90
degrees to each
other; the camera lens’ optical
path aims straight
through one of
these panels (the
right eye view),
with the other
providing the left
eye view, with
its image passing
through a beam
The Nu-View video signal hookup. The
splitter. Most of
camcorder’s composite output is fed to
the adaptor’s video input to trigger 50Hz the housing’s interior is taken up
operation of the Liquid Crystal Shutters.
www.siliconchip.com.au
by a large front-silvered mirror which
corrects right-to-left orientation of the
left eye view. And that’s about all.
The side of the device has a battery
well (for the AAA alkaline cell), an on/
off switch and the video input terminal. At the opposite side of the adaptor
there is a knob, centred amidst a pair
of sweeping curve indicators and the
legend 0 (for infinity).
This knob is the convergence adjustment to vary the position of the
stereo effect; when twisted it swivels
the internal mirror to alter the acceptance angle of the left LCS panel.
The adaptor’s inter-ocular distance is
56mm – slightly smaller than the average human’s eye separation of 65mm.
Note: the convergence knob does
not adjust interaxial separation by any
significant amount. Its job is only to
adjust the distance at which the optical
axes of the two ‘adaptor’ eye views
overlap. This in turn sets the ZPD
(Zero Parallax Distance) also known
as convergence distance.
Andrew Woods comments that
more on this effect is discussed in the
book “Foundations of the Stereoscopic Cinema” available as a free download from http://www.stereoscopic.
org/library
This convergence control is the
secret to successful and enjoyable (for
the viewer) stereoscopic video. You
can place virtually any object in front
of the stereo ‘window’ (the TV set’s
frame) or behind it. Having said that,
the unit is very accommodating in
that the eyes will compensate for any
slight maladjustment; extended scenes
November 2002 15
in its position and everything righted
itself – but rotational alignment is
important. Another time the adaptor
came adrift from the camera; perhaps
the adaptor-camera link could be better engineered.
Becoming braver, I started shooting
scenes with to-and-fro movement.
My small son, astride his trusty 16inch bike, raced towards me from 20
metres distance, passed only a metre
away, then moved off to a distant spot.
I ‘pulled’ convergence and so managed
to control the stereo window. The
result was terrific.
Summary
And here’s what it looks like from side-on. Sure, it becomes a little unweildy –
but you do get 3D!
with the wrong setting may give rise
to eye-strain; care should be taken to
avoid shooting extremely close and
very distant subjects in the one scene.
Experience
On the second day with the Nu-View
I had some real fun and found that
using the Nu-View was really quite
simple. Let’s say I would line up on a
tree in foreground, with a distant scene
behind. Having set the zoom lens and
determined my framing composition I
then set the convergence, in this case
choosing to set it on the tree; the image
of the tree in the viewfinder became a
single one, with other subject matter,
both fore and aft appearing as double
images.
You do have amazing freedom with
the zoom; in some cases I shot with the
lens at wide angle, then occasionally
shot subject matter with the zoom fully
extended.
It does help if you shoot in good
light; viewing the tape at home you
find that dark or backlit scenes are
a little murky as the tonal range is
limited by all the clutter that has been
placed in the subject-to-lens-to-viewer
path: beam splitters, Liquid Crystal
Shutters, LCS specs and so on. I also
noted that the beam splitter has its
surfaces treated with a polariser to
reduce internal reflection. Bang, there
goes another f stop of light!
It also helps if you avoid any flare in
the scene as it is most likely the flare
will be captured by only one ‘eye’ and
replay as a ghost image.
On one shooting safari, for some
reason, I noticed that the vertical
alignment had shifted (it had been perfect straight out of the box). Without
resorting to the Allen key adjustment
I merely twisted the adaptor slightly
Toshiba 3D
Way back in 1990, a Toshiba 3D
NTSC VHS-C video camcorder appeared – a ‘world first’. The SK-3D7
used two lenses and two 1/2-inch
CCD sensors. The 3D images are
viewed using an adaptor and LCS
3D specs.
The description I have is that the
“camera serially records pictures
onto a VHS-C video cassette tape
at 60 fields/second, each image
being recorded on one of two alternating fields that together comprise
one picture frame.” This the same
Field-sequential 3D system that the
Nu-View uses.
16 Silicon Chip
Toshiba’s
interesting
twin lens 3D camera, which is still
selling as a ‘collector’s item’.
However, the horizontal resolution
is only 360 lines; current Mini DV
camcorders can capture around 500
lines or more.
Video Synthesis, a company in
Ohio, currently has four ‘collector’s
items’ left – at US$10,000 each! See
www.vidsyn.com
I became thoroughly enamoured of
the Nu-View. If I had the time, I would
shoot 3D video from daybreak to dusk.
On the job, using the Nu-View on a
camcorder is admittedly a challenge
in juggling: in my case, the camera,
battery and tape weighed in at around
750g; the Nu-View adaptor was another 620g; add the AV cable and the
scales hit 1.4kg. A tripod is a help and
saves straining your wrist muscles
but does limit your shooting freedom.
Coping with the camera on/off switch,
the adaptor’s power button, the zoom
lens plus the convergence control is
quite a feat.
There is also a downside in viewing
any 3D video made with the adaptor,
which is the bother of setting up the
field sync decoder, arranging the
audience and handing out the LCS
spectacles. The view on screen is also a
trifle dim; admittedly you can help this
by cranking up the TV’s brightness,
contrast and colour saturation.
However, the biggest deterrent for
most people will be the continuous
flicker caused by the two sets of different 25 field images, the heart of the
system. In my book, only the diehard
enthusiast is going to persevere with
3D TV at present.
But at the end of the day, at the
end of the 3D shoot – I just love the
technology!
Cost of the Nu-View plus the H3D
Video Eyewear is $989. The latter includes two pairs of lightweight, wireless liquid crystal 3D glasses, custom
TV interface box, two RCA extension
cables, manuals and power supply.
What to see
Until you’re fully kitted up with
camcorder and 3D gear perhaps you
may like to preview what the pros are
www.siliconchip.com.au
Canon’s 3D Lens
Canon Inc in the USA announced
an interchangeable compact zoom
lens for the XL1 digital video
cam-corder to enable recording of
3D images.
The company explains that “While
there do exist special attachments that
can be placed on the front of conventional video camcorder lenses that
enable the capturing of 3D images,
problems have arisen as a result of
light loss and inaccurate left and right
optical axes.”
Obviously a tilt at the Nu-View!
The new Canon 3D zoom lens is
claimed to solve these problems.
They explain that a “high-precision
3D imaging optics system employed
in the lens optically merges parallax
images obtained from the left and right
doing with the medium. Much of the
material is on VHS or DVDs.
Below is a list of some of the available titles. The DVDs are mostly in
NTSC, while there are some VHS tapes
in PAL and/or NTSC. Most DVDs have
a 2D version as well as the ‘deepy’.
•
Sports Illustrated Swimsuit in
Stereo 3D
The content is from a Sports Illus
trated photo shoot featuring nubile
ladies. Watch the models pose and
the photographers work, all in ste
reo-scopic 3D.
Then there’s a biggish list of titles
derived from IMAX 3D presentations.
with a 3D ride as Johnny confronts Mr
D and fights to free his mother’s spirit.
lenses via a high-speed shutter while
the video signal is output by only one
signal line.”
It would appear that this is the same
system as the Nu-View but possibly
more elegantly executed, using as it
does, “a focusing unit that uses triangulation to measure the distance to
the subject and a motor to adjust the
mirrors inside the left and right lenses
accordingly, enabling the angle of
convergence to be set automatically.
Unlike conventional 3D systems,
with the Canon 3D zoom lens, there
is no need to set the angle of convergence manually, enabling even novice
users to easily record 3D scenes.”
It was planned to sell for US$8499
but the company decided not to go
ahead with production.
•
Alien Adventure
Look out for invading aliens as they
head toward planet Earth, in hope
of establishing a new home for their
people. They have to face Adventure
Planet, a hi-tech amusement park not
yet open to the public.... This was the
first full-length digitally animated
giant screen 3D film.
•
Encounter in the Third Dimension
A ground-breaking venture into the
realm of 3D filmmaking, with comput
er-generated imagery mixed with live
action thrills. Includes a recreation
of one of the earliest 3D movies ever
made, through to classic clips from
Hollywood’s 3D heyday during the
1950s.
•
Haunted Castle
Johnny, a young musician, travels to
his late mother’s castle to learn of his
bequest, in accordance with her final
wishes. The castle begins to come alive
as materialising spirits show. Ends
•
Ultimate G’s
Experience the thrill of flying in
an aerobatics aircraft through the
Grand Canyon, Little Colorado River
and Lake Powell. The talents of the
pilots give the audience the thrill of
a lifetime.
•
Camp Blood
My first taste of 3D, with a large
dose of mammary input. Not for the
kiddies!
As far as I could determine, the
classic 1950s 3D feature films have not
been transferred to 3D video; they have
been converted to 3D video but just
aren’t available commercially.
This is a shame as some of the titles
are classics: Hitchock’s Dial M for
Murder, Kiss me Kate, The French
Line.
Perhaps the studios who own these
titles will see the increasing interest
in 3D and release these titles commercially on 3D DVD.
(Many other 3D Video titles are
available – listed on Andrew Woods’
Website: http://info.curtin.edu.au/~iwoodsa/3dmovie/videosites.html
Where do you get ’em?
Nu-View and similar products described in this story can be obtained
in Australia from:
Mindflux: 02 9416 9619
www.mindflux.com.au
Digital Playtime:
www.digitalplaytime.com.au/
3D/index.asp
EzyDVD:
www.ezydvd.com.au/
Direct 2U: 07 5455 3554
Acknowledgement
1950s features in 3D: Sangaree and
The French Line.
www.siliconchip.com.au
Barrie Smith would like to thank Jason
Pang and Mark Giles of Mindflux for
their help in providing equipment used
in this story and, once again, is grateful to Andrew Woods at the Centre for
Marine Science and Technology, Curtin
University of Technology, Perth WA for
his technical help. We also acknowledge
Philip Heggie for a series of emails
which provided the initial impetus for
SC
these articles.
November 2002 17
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