Reducing the Operational Complexity of Stereoscopic Production Camera Systems

Reducing the Operational Complexity of Stereoscopic Production Camera

Systems

Reducing the Operational Complexity of Stereoscopic Production Camera

Systems

Michael Bergeron

Panasonic Broadcast

Hollywood Post Alliance Tech Retreat 2010Hollywood Post Alliance Tech Retreat 2010

What is 3D?What is 3D?

• 3D Describes graphics or animation where images are rendered from 3 dimensional modeling

• 3D Describes any display system with an appearance of depth

• 3D is possible without glasses but this is a very different kind of technology

• For this discussion….

3D = Stereo Video i.e., We need a left eye image and a right eye

image

3D = Stereo Video i.e., We need a left eye image and a right eye

image


How does one display stereo as 3D?How does one display stereo as 3D?• Must have a left eye image and a right eye image

• Left eye must only see left eye image

• Right eye must only see the right image

• You could use goggles with displays in them

• But for this discussion….

3D = 3D Glasses3D = 3D Glasses


Passive Glasses: projectorPassive Glasses: projector

• Two independent left and right projectors

• Orthogonal polarization blacks left picture from right eye and right from left

• Projectors must have twice the illumination

Left

Right

Left and right eye filters match the projectors

screenOrthogonal* polarizers, or specialized

color separation filters**

*e.g., For RealD ”Orthogonal” means circular/circular @ different angles

**Dolby 3D uses Wavelength multiplex visualization


Passive Glasses: single projectorPassive Glasses: single projector

• Left and right frames alternate from projector (more than twice per frame)

• Switched polarizer is synched with the projector

• Same passive glasses can be used as two projector system

Alternating orthogonal* polarizers, or specialized color separation filters**

Left and right eye filters match the projectors

L, R, L, R, L, R… screen

*e.g., For RealD ”Orthogonal” means circular/circular @ different angles

**Dolby 3D uses Wavelength multiplex visualization

e.g., 144 Frames per second


Passive Glasses: Flat Panel (Micropolarized)Passive Glasses: Flat Panel (Micropolarized)

• Left and right image appear on the display simultaneously

• Micropolarizing film on the display polarizes left image in same direction on alternating lines, and right image is polarized the other direction on the opposite lines

• Passive polarizing glasses block left image from right eye and right image from left eye

• 3D Image is ½ resolution of the display


Active Shutter GlassesActive Shutter Glasses• Left right frames alternate on 120 fps Panel

• IR emitter sends sync signal from the display

• Active glasses block left and right eye with LCD shutter as right and left images are displayed

• 3D Image is Full HD Resolution

• Full HD = 1080i for each eye, 720p 60 for each eye or 1080 24p for each eye.

• Display is capable of 1080 60p but there is no content

HDMI 1.4

Left Right

Left

Right

Right

Left

Right

Left

IR Signal


To Produce Stereo Content With a Camera System…To Produce Stereo Content With a Camera System…

1. System must link 2 cameras (i.e., align them and control in parallel)System must link 2 cameras (i.e., align them and control in parallel)

2. System must manage parallax of two imagesSystem must manage parallax of two images

3. System must correct optical or parallax errors for “good 3DSystem must correct optical or parallax errors for “good 3D

Regardless of display system to be used


Lens servos must be LinkedLens servos must be Linked

HC1800

HC

1800

Right Eyecamera

Left

Eye

ca

mer

a

Lens

Ser

vo

Sys

tem

Lens Servo System

A Camera Rig Locks Two 2D Cameras together on a rigid frameA Camera Rig Locks Two 2D Cameras together on a rigid frame

Focus, Zoom and Iris

Focus, Z

oom and Iris

Imagers synchronized

Time-code m

atched

1. System must link 2 cameras (i.e., align them and control in parallel)System must link 2 cameras (i.e., align them and control in parallel)




Converge behind Converge in front

Lch

Rch

Lch

Rch

Lch

Rch

Convergence Plane Can Be adjustedConvergence Plane Can Be adjusted


When editing or switchingWhen editing or switching

convergence plane must be consistent with perspectiveconvergence plane must be consistent with perspective

Wide Shot Medium Shot Close Up


IO too narrow

Inter-ocular distance impacts scale perspective & comfortable 3D viewingInter-ocular distance impacts scale perspective & comfortable 3D viewing

IO too wide

Disparity is too little

Lch

Rch

Disparity is too much

Lch

Rch

3D is imperceptible 3D is painful


?? !!

Inter-related factors impacting disparityInter-related factors impacting disparity

Imager Inter-ocular focal convergencesize distance length angle

closest most distantobject object

Display size viewing distance viewer inter-ocular


12 3

Side By Side RigSide By Side Rig

•Minimum inter-ocular > 0

•Tight close up is a problem

•Minimum inter-ocular depends on camera/lens size

•Wider Inter-ocular is possible

•Good for shooting distant objects

L

R

Top View

io


•Minimum inter-ocular = 0

•Camera can be any size

•Good for shooting close objects

•Beam-splitter acts as a polarizer

•Additional alignment challenges

L

L

R

R

Side View

Front View

io

Beam-splitter rigBeam-splitter rig


Left Right

LeftRight

Left Right LeftRight

Vertical convergence error Distortion error Focal length mismatch error

Regardless of individual left and right picture quality. L/R Mismatches lead to BAD 3D

Variable picture quality can be forgiven. Bad 3D ?

GOOD 3D

System must correct optical or parallax errors for “good 3DSystem must correct optical or parallax errors for “good 3D


!!

Ways to correct 3D ErrorsWays to correct 3D Errors• Optical/Mechanical

• most expensive

• Not necessarily possible

• Post production

• Most common

• Not useful for live production

• expensive

• Real time processing

• expensive


Can I scale the system down?Can I scale the system down?1. System must link 2 cameras (i.e., align them and control in parallel)System must link 2 cameras (i.e., align them and control in parallel)

Lower cost systems tend to have looser alignment specificationsLower cost systems tend to have looser alignment specifications


Can this be done without a 2 person crewCan this be done without a 2 person crew

3.3. System must correct optical or parallax errors for “good 3D System must correct optical or parallax errors for “good 3D

Additional post 3D correction will erase any cost savingsAdditional post 3D correction will erase any cost savings

3D Rigs represent quite a bit of engineering excellence and operator skill


These 2 oppose

one another

Operation should move From “Guitar Hero” Easy…Operation should move From “Guitar Hero” Easy…

To “Guitar Hero” MediumTo “Guitar Hero” Medium

Iris

Focus

Zoom

Iris

Focus

Zoom

Convergence

?


HC1800Right Eyecamera

Left

Eye

ca

mer

a

Par

alla

x ad

just

Lens

Ser

vo

Sys

tem

Focus, Zoom and Iris

Focus, Z

oom and Iris

Can We Integrate Lenses and Cameras?Can We Integrate Lenses and Cameras?

Parallax adjust


Lens Servo System

Advantages of small format fixed lens form factorAdvantages of small format fixed lens form factor• Small imager permits side by side configuration with >2.5” inter-ocular

• Lenses assembled tracked and optimized with imagers during assembly

• Integrated servo controlled optics employ look up tables for accurate tracking

• User interface can support an additional convergence control on camera and on remote

• Can take advantage of in-camera electronic optical correction for 3D correction


HJ17x7.6

compensation circuit

calculate the amount

of the compensation

HJ22x7.6

Lens positioning data

Lens model number

CAC database

IRIS/FOCUS/ZOOM

Gch

Rch

BchY

Pb

Pr

lens

compensation circuit

CameraProcessing

HA22x7.8

HA16x6.3

Lens model APosition (I,F,Z )

P1

P2

P3

Aberration

Spacial Position

Compensated Aberration

*CAC activate in real time adaptively with lens condition such as zoom, iris and focus position.

Chromatic Aberration Compensation CACChromatic Aberration Compensation CAC

• Employ same type of LSI

• Convergence added to LUT

• Correct for L/R lens differences

• Can adjust for distortion as well as chroma aberrations


Why This Camera First?Why This Camera First?


Complimentary ProductComplimentary Product• This was the biggest hole in the market

• Small Format means small format

• If you could shoot project with 2D small format camera this camera may be perfect

• Fixed Inter-ocular impacts camera placement

• The rules of shooting good 3D still apply (so you still must learn them)

• This camera is meant to help you learn them!


Under StudyUnder Study

L

R

Maximum convergence angle?

Inter-ocular

< 2.5” but how much smaller?

sensitivity? This is often determined late in development

Zoom Range?Impacted by

If/how automatic convergence is accomplished

Goal is to minimize bad 3DGoal is to minimize bad 3D

AG-3DA1

What We Know

- Lens Under review

- Recording Media 2 x SD card

*L / R each recorded to one card

- Rec. Format AVCHD PH mode

1080/60i, 50i, 30p, 25p 24p(Native)

720/60p, 50p(Native)

- Lens Adjustment Focus, zoom, iris, Convergence

- VF, LCD L,R, or Mix (Overlay)

- Microphone Internal Stereo Mic

XLR (optional: AG-MYA30G)

- Meta Data TBD

- Weight (Target) Under 3.0kg

- Power Consumption 16W

- Power Battery, AC Adapter

1. Twin Lens (2 Optical Components)　　

2. Lightweight and Compact　　

3. Easy Operation　　 lenses matched during manufacturing


BT-3DL2550BC &Professional 25.5-inch 3D LCD Monitor

- Panel 25.5-inch IPS panel

WUXGA (1920x1200)

- 3D Filter Type Xpol polarizing filter

- Color Space Same as 2550

- New Function Pixel-to-pixel for 720P displaying

- 3D Interface HD-SDI x 2

*w/ 2: L, R simultaneous

*w/ 1: *Line-by-line, Side-by-side

DVI-Dx1 *Line-by-line, Side-by-side

- Power Supply DC24V

- Dimensions 599(W) x 410(H) x 100(D) mm

- Std. Accessory 3D polarizing glasses (2)

AC adapter

1. Professional 3D LCD Monitor

2. Using Xpol Polarizing Filter

3. Professional I/F Support HD-SDI x 2 for simultaneous L,R 3D signals

RR


1. With new professional 3D monitor

HD-SDI x 2*L,R simultaneous

2. With other 3D monitors

HD-SDI x 2*L, R simultaneous

3. With external recording device

3. With consumer TV (PDP)

AstroDesign

BT-3DL2550

JVC

HDMIVer.1.4 Ver.1.3



*S-two, Codex, KG, SR

P2HD(L, R dual card rec.)

HDMIVer.1.4

*Field/Frame sequential

Consumer TVi.e. 3D-PDP

?




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Reducing the Operational Complexity of Stereoscopic Production Camera Systems