Poynton’s Vector – Tier 1

2026‑02‑03

Register at Circle.so.

A decade ago, I was contracted by SpectraCal, now Portrait Displays, to write a monthly 1000-word (2-page) note on a technical topic of my choosing. The series was called Poynton’s Vector; more information, and the issues themselves, are available.

I plan to renew the idea. I have many unpublished pieces of technical analysis and writing that I want to get out into the world! So I thought: Share them as kind of “beta” with my enthusiastic supporters to have discussion and get early reactions. Some of these pieces have recently been, or will be, presented at my seminars and workshops. I expect many of these pieces to show up in public at some time, for example, in a future book.

Development of these pieces took, and continues to take, a considerable amount of my own time, so I seek some revenue. Here’s the proposal: I invite you to subscribe to delivery once every four weeks, on a Monday (planned to start Tue Mar 3), of a fresh, current topic in a 2‑, 3‑, or 4‑page PDF, followed by a 30‑minute prerecorded video update delivered Monday two weeks later – maybe on the topic of the current month’s document, maybe something related, or maybe something else.

Topics in the queue:

  • Gamma and Log coding: What are the deep fundamentals behind these two camera coding schemes? How are they similar? How do they differ?

  • Controls: What do the controls labelled BRIGHTNESS, CONTRAST, GAMMA, LIFT, GAIN do, in visual, perceptual terms? Why is the term contrastiness more useful and accurate than contrast?

  • Is the physical response of film logarithmic? Many people think so, but it’s not. What’s the essence of the math?

  • Why are camera exposure time settings in 1/3-stop intervals instead of 1/2-stop? What’s so special about 1/3-stop? What’s magic about the ratio of 1.259?

  • What are HDR gain maps, commercialized by Apple and Google? Are they important?

  • How do photographic light meter measurements (LV, EV) of photography and cinematography relate to the light measurements of science (illuminance [lx], luminance [nt])?

  • What are the advantages and disadvantages of the absolute (PQ) and relative (HLG) schemes for HDR distribution? Is HLG scene-referred? (No, for any reasonable definition of scene-referred.)

Subscribers might include:

  • colour assistants & junior colourists

  • early- and mid-career DITs

  • technically-minded DoPs

  • post-production supervisors

  • data management technicians, media engineers, and mastering engineers

  • VFX supervisors, color pipeline TDs

The package is available to you every month, for less than the cost of a cappuccino and a croissant once a week: CAD 20/month, CAD 50/quarter, or a year’s subscription for CAD 180. These subscriptions are like magazine subscriptions: you start receiving issues when you subscribe. Back-issues of PDFs and video recordings will be available at a small fee.

Register at Circle.so. Issue 101 is available now; issue 102 will be available Mon Mar 09, with issues monthly thereafter.

If you want information delivered in a comparable fashion, but at a higher technical level, you might be interested in Tier 2.

Charles Poynton is an independent researcher and image/colour scientist based in Toronto. He wrote the book Digital Video and HD Algorithms and Interfaces, now in its second edition. Thirty five years ago, he chose 1080 image rows for HD standards, by which “square pixels” were established for HD and digital cinema. He earned his PhD in 2018 from Simon Fraser University with a dissertation entitled Colour Appearance Issues in Digital Video, HD/UHD, and D‑cinema. He is a Fellow of SMPTE, Colorist Society (CSI), and IMIS (formerly BKSTS). ∎