HDR & ACES: a 1-day Technical Seminar

with Charles Poynton hosted at Mr X Gotham, Manhattan On Thu Aug 11, in collaboration with Mr X Gotham (Manhattan), I’ll present a one-day technical seminar on HDR and wide colour gamut for d-cinema, HD/UHD/4K/8K. ACES is important in high-end production, and is becoming increasingly useful in CGI/VFX and DI. The ACES block diagram serves …

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Practical Aspects of HDR (in Oxfordshire, July)

On Tue July 12, at Heythrop Park in Oxfordshire (90 min or so from London), John Watkinson presented a 5-hour seminar, Practical Aspects of HDR: Implementation and Deployment, as part of the SMPTE/HPA UK Tech Retreat. John covered the material that I presented at HPA Tech Retreat in Palm Springs in Feb., with an update concerning emerging …

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Emergent Technology in D-cinema and UHD/4K

High Dynamic Range, Wide Colour Gamut, and ACES 1.0 A Seminar with Charles Poynton hosted by SKYLAB HQ/Screen Dragon, Vancouver, BC Tue Feb 23, 10:00 – 17:00 Three important emerging technologies touch acquisition, post production/DI (especially colour grading), studio display, mastering, and distribution for cinema and UHD/4K: high dynamic range (HDR), wide colour gamut (WCG), and ACES 1.0. …

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Display black setting & validation

Here’s a thought experiment. On an 8-bit computer display (that is, a display nominally operating to the sRGB spec, where code 0 is black and code 255 is white), set black level (commonly, “BRIGHTNESS”) to what you think is correct. Put up an image that is predominantly solid black (code 0), but having a patch at code value 0 upon which …

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Two requests of home theatre enthusiasts

I make two requests of home theatre enthusiasts: 1. Please don’t use the term luminance to refer to the video signal that conveys the achromatic (greyscale, or “black-and-white”) colour component. The definition of luminance has been established by the governing body of colour science (the CIE), and it’s a special word for colour and image scientists. CIE …

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“6-axis” calibration

“6-axis” calibration refers to a video display’s adjustment of the individual colours displayed for red, yellow, green, cyan, blue, and magenta colours in the input signal. The scheme also goes by the generic name “colour management system” (CMS, no relation to desktop graphics colour management systems), and by various vendor-specific trademarked terms. There is no standard …

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Greyscale charts in video and HD

Nine-step (“EIA”) charts have reflectance values arranged in an exponential relationship, r = 0.030 10^(0.18175 k), where k ranges 0 through 8. The reflectance steps correspond to uniform increments of optical density. These charts are typically called “logarithmic.” Eleven-step (“ITE‑J”) charts are designed to have reflectances that, when imaged by a video camera (having an OECF comparable …

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Gamma in studio and CE

HD content (a Blu‑ray movie for example) is properly and commonly mastered with displays (such as Sony BVM‑D32) having 2.4 gamma, at 100 nt reference white, with about 1 lx ambient illuminance, and a surround of about 1 nt (that is, 1% of reference white, a “very dim” surround). The 2.4 gamma is specified in BT.1886, and is well approximated by …

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