CINEMA EOS ON SET HDR/WCG ECOSYSTEM
WHITE PAPERCINEMA EOSCINEMA EOS ON-SET HDR/WCG ECOSYSTEMWritten by Larry ThorpeCustomer Experience Innovation Division, Canon U.S.A., Inc.For more info:cinemaeos.usa.canon.com 2016 Canon USA, Inc. All rights reserved.
Cinema EOS On-set HDR / WCG EcosystemAbstract.High Dynamic Range (HDR) and Wide Color Gamut (WCG) are now widely accepted as constitutingimportant attributes to overall enhancement of the viewer experience – for home and for theatricalviewing. While closely associated with the emerging UHD / 4K they both can equally apply tocontemporary HD / 2K systems. Today’s digital productions that entail HDR augmented by WCG requiresignificant changes to practices on-set. The Lenses used in these productions require the highestcontrast ratio and tight management of highlight related optical artifacts. Cameras must be capable oforiginating imagery having credibly high exposure latitude. Reference Displays capable of portrayingboth HDR and WCG become essential to on-set acquisition workflow for the filmmakers to have completeconfidence in the process.This paper will outline the numerous design strategies in a unique second generation digitalcinematography production system intended to originate imagery in 2K / HD / 4K / UHD formats that haveboth High Dynamic Range (HDR) and Wide Color Gamut (WCG). The system includes the cine lens, anew digital camcorder, and an on-set reference display that share a coordinated system designconforming to the ACES 1.0 system developed by the Technical Council of the Academy of MotionPicture Arts and Sciences [1]1.0It will be shown that the optical dynamic range of the lens plays a critical role in originating highquality HDR and that its spectral transmittance is central to originating WCG imagery.2.0 Canon’s EOS C300 Mark II digital cinema camera has a 15-stop exposure latitude that allows it tooriginate impressive HDR imagery. The camera offers a choice of wide color gamuts including the newITU-R BT.2020 wide color gamut, and a Cinema Gamut that is even wider.3.0 Canon’s new portable 24-inch on-set reference display DP V2410 was designed in concert with theEOS C300 Mark II camera. The display includes HDR functionality. It directly accepts the 4K / UHDRAW signal output of the camera and internally deBayers this for realtime monitoring. The displayapplies the ACES-based IDT processing that takes the camera’s 4K/UHD RAW signal output into anACES 1.0 space. The common standard ASC CDL color correction system within the reference displayallows control of Slope, Offset, Power and Saturation according to this standard. The display supportsboth Canon Log 2 and Log 3 signal inputs and signals encoded according to the PQ based EOTF(SMPTE ST-2084) and the Hybrid Log Gamma (HLG) EOTF. It separately accepts the ACESProxy 10-bitserial digital output of the C300 Mark II camera to support on-set grading of program material beingrecorded on board via the XF-AVC codec.INTRODUCTIONHDR and WCG began as separate technological movements but over the past year have been steadilyconverging as a consequence of:1. Better understanding of their respective implications2. Broadening tests worldwide [2],3. Publications of important reports [3],4. International standardization bodies undertaking both studies and actual standardizationprocesses [4].2
Wide Color Gamut (WCG) came to a successful fruition with the publication of the ITU-R BT.2020production standard for UHDTV [5]. High Dynamic Range is presently garnering more attention aroundthe world as numerous entities in both the television and the theatrical motion picture communitiesgrapple with the challenges of rationalizing an end-to-end HDR ecosystem.The ACES system development was tailor made to support HDR / WCG program production. It isfortuitous that Canon’s debut of the new EOS C300 Mark II HDR camera and the DP V2410 referencedisplay approximately coincided with the formal publication of the ACES 1.0 system. Both of theseproduct developments were significantly guided by ACES 1.0.THE HDR / WCG ECOSYSTEMThe on-set ecosystem for HDR and WCG on-set origination is reproduced in Figure 1. HDR for digitalmotion imaging starts with a lens having a high contrast ratio that can deliver the finely nuanced tonalgradations for the nominally exposed signal, while accurately reproducing specular highlights in thescene, and protecting against optical artifacts stimulated by severe off-axis highlights. This combines withan associated camera image sensor having the requisite exposure latitude, a high bit-depth A/Dconversion system, and a camera OETF that protects the integrity of that latitude within the associateddigital recording system [6].The on-set ecosystem is completed by an on-set HDR reference display that empowers the productionteam to creatively adjust lighting and effectively assess what is being captured in different scenes.Figure 1Summarizes the core elements of the on-set digital acquisition system that bear uponHDR and WCG origination – the Cinema EOS lens, C300 Mark II camera, and reference display DPV2410Wide color gamut also starts with the spectral response of the lens, followed by that of the Color FilterArray (CFA) and the image sensor, the optical IR filter, and followed in turn by the necessary linearmatricing of the RGB primaries.When shooting on set, it is typically not convenient to use floating-point values for monitoring. The ACESsystem resolves this by including an integer encoding that can be transported from the camera over anHD-SDI link for on-set monitoring. This is a lower-quality ACES encoding called ACESproxy not intendedfor recording. On significant productions it has become customary for the Director and Director ofPhotography to do a basic color grade that establishes the specific “look” they jointly seek for each scene.This becomes the all-important initial reference for the postproduction team tasked with the final grading.The ACES system includes a standard for applying the look on-set in ACESproxy space, and thenapplying it again in DI such that the original look is preserved. This is the intended workflow for creating“look” metadata using ASC CDL values.3
1.0THE HDR LENSThe current industry discussions on HDR and WCG center largely on the associated camera, recorders,workflow, and infrastructure. It is sometimes overlooked that the origination of HDR imagery starts withthe lens that is coupled to the HDR camera [6]. It is the task of the lens to translate the enormous rangeof luminance possibilities emanating from real world scenes to an optical representation on the cameraimage sensor that is as faithful as possible to that scene. The light path through the lens is fraugh t withmultiple optical challenges and the new high interest in HDR has elevated related complexities.Figure 2The HDR system relies upon the effective dynamic range of the lens as well as that of thecamera image sensorTo do justice to the HDR camera the lens must have: Requisite contrast ratio over the nominally exposed image – that is, from black to the diffusereference white level – to ensure the excellent tonal reproduction expected from an HDR systemand, most especially, clarity of detail in dark shadowed areas of the scene. Clarity of reproduction of specular highlights within the scene – be it indoor or outdoor – withminimization of any associated ghosting and flaring artifacts Tight management of any reflections within the lens barrel that might contaminate the imagewith flare and ghosting Control of off-axis highlights that can cause veiling glare and flares1.1Sophisticated Design Simulation is Critical to Achieving HDR Optical PerformanceHigh zoom ratio lenses dramatically alter the angle of view of the lens which is attended by a huge4
diversity of light ray angles entering the lens system. Over many years Canon has developedincreasingly powerful computer simulation systems that facilitate detailed examination of the passage ofsuch light rays through the entire optical system and their behavior at all conceivable lens settings. Thesimulation can predict the individual paths of the lights rays and their relative strengths under all forms oflighting conditions. Identifying undesirable internal reflections and introducing the requisite multiplecounter strategies is central to ensuring the highest optical HDR capability.1.2Lens Contrast Ratio:Today’s digital cameras readily achieve a Luma signal to noise specification of 60dB or better whichequates with a 1000:1 dynamic range for the nominally exposed signal (capped black to reference white).Thus the associated lens must have a contrast ratio in excess of this to do full justice to the cameracapability.If a lens has a transmissivity in the neighborhood of 80 % then the black reproductioncapability must be lower than 0.1% to exhibit that level of contrast ratio.Central to achieving a high contrast ratio is minimization of inner reflections in all glass elements. This isachieved by sophisticated multilayer (to manage all visible wavelengths) optical coatings on each andevery element surface. The coating technologies elevate the light transmission through the lens systemwhile simultaneously suppressing contamination of scene blacks – thus raising the overall lens contrastratio. Figure 3 suggests two scenarios that indicate how critically important it is to lower the blackcontamination to achieve a high contrast ratio.Figure 3Illustrating the dual role of optical coatings in elevating lens light transmission whilelowering black contamination – with two scenarios for the black levelCanon’s professional lenses utilize multi-layer coatings that are effective across the entire range ofwavelength of visible light, and they are all uniquely developed by Canon. In a multi-element zoom lensthese coatings are enormously effective in elevating the transmission of the light through the entire opticalsystem as well as playing a major role in shaping the spectral characteristic of the lens system. They arealso central to curtailing the light scatter caused by unwanted reflections that elevate what should bedeep blacks in a scene while also causing flare around high intensity elements within a scene.Internal light reflections can also be caused by light scattering from the edges of the glass elements andin order to prevent this, the edges of each glass is designed and processed with special anti-reflectionpaint made of high refractive index medium and minimal black particles.5
Multiple reflections can also cause the creation of ghost artifacts.designed HDR lens can overcome some of these optical artifacts.Figure 4 shows how a carefullyFigure 4Examples of glare and ghosts within a lens caused by unwanted reflections and theireffective elimination with high quality optical coatings1.3Specular Highlights within the Framed Scene:A critical expectation from the HDR imaging system is the faithful reproduction of small specular highlightswithin the scene and here a variety of additional optical considerations arise. Small intense specularhighlights that are in focus should be reproduced as small circular spots with crisp outlines and smoothdelineation. It is the faithful reproduction of such highlights that properly exploit the subjective benefits ofHDR. Out of focus speculars should be reproduced as enlarged circles with smooth bokeh. Glassmaterials, optical coatings and a multi-frame aperture all contribute to this precision clean reproduction ofspecular highlights.1.4Intense HighlightsLenses can exhibit vulnerabilities to intense external off-axis highlights (such as the sun or a studio light)that can stimulate a variety of unexpected optical interferences. Strong unwanted reflections that mightbe stimulated by off-axis intense highlights can separately create another mechanism of internalreflections that spill across the entire image plane – and is termed veiling glare. As well as the measuresdescribed for the glass elements themselves there are additional optomechanical techniques that aremobilized to eliminate or attenuate the strong reflections that can take place within the lens barrel.Angled surfaces and junctures of surfaces can all create reflections and accordingly special antireflection paints having ultra-fine black pigment grains have been developed that are made of highrefractive index medium. Light blocking grooves, knife edges, and other mechanical strategies aremobilized. An electrostatic flocking process directly applies an extremely fine pile to mounting surfacesthat also require an anti-reflection finish. This technique is extremely effective because the pile standsperpendicular to the wall surfaces. This is especially effective in the long barrel sections of zoom lenses.Figure 5 summarizes some of these optomechanical counter strategies.6
Figure 5Simplistic showing of some of the optomechanical strategies used to curtail unwantedreflections around the lens element edges and their associated mountings2.0AN EXTENDED DYNAMIC RANGE DIGITAL CAMERAThe new EOS C300 Mark II centers about a totally new 4K CMOS image sensor design [7]. This wasspecifically developed to extend the overall image performance of HD beyond that of the original EOSC300 while further supporting the alternative 2K cinema format. The new C300 Mark II also originates achoice of high performance UHD or 4K cine video – constrained, however, to a maximum picture capturerate of 30 fps progressive.A 15-stop dynamic range is provided by a new photodiode design that simultaneously lowers the noisefloor while elevating the saturation level – offering excellent HDR functionality. The camera can managea far greater range of scene Illuminance levels by deployment of a choice of 5 separate ND settings and agreater range of ISO sensitivity settings.The separate video components that are directly readout in parallel from the 4K image sensor areprocessed in a quite different manner than those of the original C300 – utilizing a novel sample rateconversion system to further reduce aliasing and provide a more benign appearance to noise within theformulated 2K / HD RGB 444 components. 2K / HD Picture capture rates have been extended to amaximum of 120 fps progressive.A totally new camera OETF transfer function was developed tomanage the high dynamic range – it is termed the Canon Log 2 curve. The camera can capture both theHDR and the WCG with on-board recording in the new XF-AVC codec. Alternatively, they can beexternally recorded via the 4K / UHD RAW output, or via realtime RGB or YCrCb component sets in thecase of 2K/ HD.7
IMPLEMENTATION OF THE ON-SET HDR / WCG ECOSYSTEMCanon undertook a coordinated design to produce an on-set digital motion imaging system having HDRfunctionality. The lens-camera system that originates HDR has been described. What now becomesimportant is how to effectively use that camera to originate imagery where creative HDR is desired forcertain scenes. Anticipating the ultimate portrayal of HDR imagery on new HDR displays (having highluminance levels and high contrast) places a special burden on those originating that imagery. Theimages need to be accurately displayed on-set on an appropriate reference display. This starts with theability to accurately portray deep black levels on set. The ability to capture very dark objects and verybright objects within a single scene requires structuring video that preserves all of that information until itfinally reaches a display capable of approximating the luminance levels of the original scene.The heart of the on-set HDR ecosystem is a unique 4K reference display developed by Canon – the DPV2410. This is a portable (weighing only 26 lbs.) display having a 24-inch display diagonal. It can be ACor battery powered.Figure 6The Canon on-set HDR / WCG ecosystem consists of the tight system integration ofthese two key products – the EOS C300 Mark II camera and the DP V2410 reference displayThe DP-V2410 reference display is unique in accepting the 4K RAW output of the EOS C300 Mark IIcamera and internally debayering this 10-bit Log 2 encoded signal [8].Figure 7The camera (on the right) sends it 4K RAW output via the 3G SDI serial interface to thereference display (center) where it can be looped through to any of a wide selection of external recorders8
THE GUIDANCE OF ACESCanon has actively participated in the development work of the Technical Council of the Academy ofMotion Picture Arts and Sciences that led to last year’s release of the ACES 1.0 system. Thiscollaboration profoundly influenced the coordinated system approach that Canon took to the new C300Mark II camcorder and the DP-V2410 on-set reference display. Canon has also actively participated inthe supporting work of the Technical Committee of the ASC—see Figure 8.Figure 8Conveying a sense of Canon’s active collaboration with the Technology Councilof AMPAS and the Technical Committee of the ASCThe basic intent of ACES is to support high dynamic range, wide color gamut, and high bit depthworkflows and to enable seamless interchange of high quality motion picture images – regardless of theimage source. It creates a common digital image format that facilitates postproduction processing ofdiverse original image formats.Figure 9Outlining the overall process of the Academy Color Encoding System (ACES)9
The workflow strategy begins with the design of an Input Device Transform (IDT) for each specificCamera – Figure 9. The IDT transforms the unique tonal and color reproduction of the camera to acommon linear light representation according to the Academy Color Encoding Specification (ACES) –SMPTE Standard ST 2065-1. The ACES system is a large container that preserves all of the camerainformation through use of 16-bit half-floating point values that cover 33 stops of dynamic range, and acolor space having wide virtual RGB primaries that encompass the entire visible color gamut. Thisrepresentation can then be manipulated by the grading process without any losses. All of themanipulation (color correction, VFX) is supported by metadata. The original source material is nottouched.The DP-V2410 is intended for on-set grading and does not require the precision and huge dynamic rangeand color space of the full ACES system. Accordingly, the 18-bit processing engine of the DP-V2410deploys the basics of the ACESproxy (described below) processing to implement the requisite grading.3.0THE ON-SET HDR / WCG REFERENCE DISPLAYThe DP-V2410 deploys a powerful 18-bit processing engine that includes the core of the ACES system.The “scene referred” input 4K RAW Log encoded signals are debayered and converted to ACES RGBrelative exposure values and passed through the IDT transformation for the C300 Mark II camera beforeentering the ACES color space for grading.Figure 10The 4K reference display deploys a powerful 18-bit engine to internally implement an onset ACES system that works directly with the EOS C300 Mark II cameraThe DP-V2410 incorporates a color grading capability conforming to the ASC Color Decision List (ASCCDL) format. The images are then mapped back to a linear light representation at a high bit depth. Toview these image manipulations the output must be rendered to a scene viewing state – which is the roleof the Reference Rendering Transform (RRT). The RRT transforms the linear light scene referred systemto a display referred (output) color space. Its specifications were designed to produce an image thatwould be subjectively pleasing on any display (this is analogous to the film printing process). The finaltransformation is via the ODT -- that makes the final mapping of dynamic range, electro-optical transfercharacteristic, color gamut, and bit depth to precisely match those of the Canon 10-bit DCI-P3 referencedisplay panel.If the EOS C300 Mark II is alternatively originating 2K / HD the related Canon Log 2 encoded videocomponent sets (either RGB 444 or YCrCb 422) are sent via the same 3G/HD-SDI serial interface
originate impressive HDR imagery. The camera offers a choice of wide color gamuts including the new ITU-R BT.2020 wide color gamut, and a Cinema Gamut that is even wider. 3.0 Canon’s new portable 24-inch on-set reference display DP V2410 was designed in concert with the EOS C300 Mark II camera. The display includes HDR functionality.
EOS 7D Mark II EOS 7D EOS 90D ** EOS 80D ** EOS 77D ** EOS 70D EOS 60D EOS Rebel T8i ** EOS Rebel T7i ** EOS Rebel T6s EOS Rebel T6i EOS Rebel T5i EOS Rebel T3i EOS Rebel SL3 ** EOS Rebel SL2 ** EOS Rebel SL1 EOS Rebel T7 ** EOS Rebel T6 EOS Rebel T5 EOS Rebel T3 EOS Rebel T100 ** EOS
AE-1 Program AL-1/AV-1/EF-M AT-1 T90 EOS 1/EOS 1N (not with SCA 311) / EOS 600/ EOS RT / EOS 630 EOS 620/EOS 650 EOS 100 / Elan EOS1000 / EOS1000F/ EOS 1000 FN / Rebel / Rebel S / EOS 1000N IX / EOS 500N, Rebel G / EOS 50 / EOS 50E / EOS 55 / EOS Elan 2 / EOS Elan 2E / IX 7 / EOS 300, Rebel
Canon EOS 650D/Rebel T4i/Kiss X6i Canon EOS 600D/Rebel T3i/Kiss X5 Canon EOS 550D/Rebel T2i/Kiss X4 Canon EOS 500D/Rebel T1i/Kiss X3 Canon EOS 450D/Rebel XSi/Kiss X2 Canon EOS 3000D/EOS 4000D - warning: please see notes below Canon EOS 1500D/EOS 2000D/Rebel T7/Kiss X90 Canon EOS 1300D/Rebel T6/Kiss X80 Canon EOS 1200D/Rebel T5/Kiss X70 Canon .
As of September, 2010 Canon offers six EOS Digital SLRs with HD Video capability: the EOS-1D Mark IV, EOS 5D Mark II, EOS 7D, EOS 60D, EOS Rebel T2i and EOS Rebel T1i. Here’s how they compare in terms of video specifications: Feature’ EOS 1D’Mark’IV’ EOS’5D’MarkII’
Canon EOS 5D EOS 20D EOS 30D EOS 40D EOS 50D EOS 350D, Rebel XT EOS 400D, Rebel XTi EOS 450D, Rebel XSi EOS 1000D Rebel XS Nikon D40, D40x D50 D60 D70, 70s D80 D90 D200 D300 D700 Olympus E3 . underwater housing for the Sony HDV Handycam HDR-SR11/SR12 is one of the smallest, lightest
EOS Rebel T4i T6i EOS 5D Mark II, Mark III EOS Rebel SL1 EOS 7D (all); EOS 6D EOS Rebel T3i, T3 EOS 60D 80D EOS Rebel T1i, T2i Not every model has the same capabilities and video features; some of the differences include: FULL HD VIDEO AT 1920X1080 PIXELS All models (as of mid-2016) except the EOS
Images HDR et rendu HDR Images HDR Rendu HDR Définitions Principes Comparaison avec les images classiques Construction des images HDR Logiciels Formats. Historique Utilisation des images HDR pour le rendu 3D Intérêt du rendu HDR Limitations Solutions pour l'affichage.
Cambridge IGCSE Accounting is accepted by universities and employers as proof of an understanding of the theory and concepts of accounting, and the ways in which accounting is used in a variety of modern economic and business contexts. Candidates focus on the skills of recording, reporting, presenting and interpreting financial information; these form an ideal foundation for further study, and .
