SDR, HDR and Dolby Vision

Source: Vimeo – ‘What You Should Know About Dolby Vision for Your Content Creation and Viewing Experience’

How Should We Deal with Color Distortion in an Era of Fragmented Viewing Environments

One of the most fundamental concerns in image-making is how the finished image will actually appear to the viewer.

Unlike the past, today’s content is consumed across a wide range of display environments, each with its own characteristics: theaters, TVs, smartphones, tablets, and monitors. The same image may appear brighter on one screen and colder on another.

As a colorist, I have always found it unsettling that the color intended in grading can be altered depending on the viewing environment. Color carries intent. And once that intent is distorted, the emotion and message of the image shift with it.

This is not only a personal concern. It is a structural issue shared by many image-makers working today.

The white-gold / blue-black dress debate also arose from color distortion under different viewing conditions.

“Bring the creator’s intent all the way to the viewer’s eyes.”

When I first came across this line in a Dolby Vision brochure, it felt as though it was pointing toward an answer to a long-standing concern.

I first encountered Dolby Vision as an image enhancement technology used on OTT platforms. Its wider tonal range and expanded dynamic range were clearly attractive in visual terms. But more than the spectacle of improved specs, what felt truly significant was the system itself, designed to prevent distortion.

The idea that an image could be managed so that it remains within the creator’s intended range regardless of the playback device felt fundamentally different from conventional color management.

If Dolby Vision were to become a new standard, I believed that much of the persistent anxiety around distortion in production could finally be reduced. That belief led me to build a Dolby Vision facility and prepare for the future in which it might become standard practice.

The HDR Era, but the Problem Remains

Source: Dolby – ‘Dolby Vision vs. SDR’ / Left: SDR, Right: Dolby Vision

Over time, we have reached a point where most viewing devices can now play Dolby Vision. And yet, the original value of Dolby Vision is still not being fully used.

The simplified idea of it as merely “a brighter, sharper technology” has reduced Dolby Vision to a visual style. As a result, discussions in production often go no further than preference-based reactions such as, “It’s too punchy and hurts the eyes,” or “The old way looks better.” The conversation remains at the level of impression, rather than engaging with the technology itself.

Under this perception, Dolby Vision adoption has repeatedly been pushed aside. Korean content, including K-pop, is distributed globally across more platforms than ever, yet still tolerates color distortion while relying on older production assumptions.

To address this long-standing issue, Dolby Vision needs to be understood not as a stylistic option, but as an ecosystem that spans both production and delivery. What is needed is not another discussion about the “look” of Dolby Vision, but a more fundamental conversation about how it changes the way images are handled, and how production systems are structured.

Dolby Vision is less a technology for making images look prettier than a framework for making image delivery more reliable. At this point, the more important question is how to understand and use that framework.

The difference between SDR and HDR in brightness and color reproduction range.

HDR (High Dynamic Range) is a technology that allows video to represent a wider range of brightness, making luminance reproduction closer to what we perceive in the real world. Compared to SDR (Standard Dynamic Range), it can retain brighter highlights and richer shadow detail, adding more depth and dimensionality to the image.

SDR (Standard Dynamic Range) refers to video formats that predate HDR. While it is more limited in brightness reproduction, it remains highly compatible with most modern production systems and viewing environments. Most commercials and music videos are still mastered in SDR.

Dolby Vision is one of several HDR formats, designed to optimize video for different display environments. Even when display performance or viewing conditions vary, it aims to preserve the luminance and color balance intended by the creator as consistently as possible.

SDR: A Standard Built on Human Adaptation

SDR is a set of rules for recording and reproducing light. It has remained the dominant standard for a long time since the earliest days of moving images.

One reason SDR was able to hold that position despite changing viewing environments is that it was built on the assumption that humans perceive brightness relatively. Differences between displays and environments were expected to be corrected by the viewer’s own visual adaptation, allowing a reasonably consistent experience within a certain range.

Source: Dolby ICC HDR Experts Day – The human eye perceives patches of identical luminance differently depending on the viewing environment.

An SDR signal contains brightness information for each pixel, but it does not define those values absolutely. It only establishes relative differences, from the brightest value to the darkest, on a scale of 0 to 100. The actual luminance of each pixel is left entirely to the performance of the monitor.

The standard assumes a dark living room as its baseline viewing environment, while also assuming that deviations in other environments will be compensated for by the human visual system. This is why SDR content can generally play across a wide range of devices without major transformation.

But today’s viewing environments are no longer limited to the dark living room. Displays have become far more diverse than before, and the variation between them has grown accordingly.

HDR: Toward an Absolute Value of Stimulus

HDR begins from a completely different premise. Instead of relying on human adaptation, it assumes that a more reliable approach is to define light in exact values.

Source: Dolby ICC HDR Experts Day – The PQ model mimics the way humans perceive brightness.

To do this, HDR is based on the JND model, which quantifies the intensity of light as perceived by the human visual system, and stores and reproduces luminance in measurable values from 0 to 10,000 nits. In HDR, light is no longer treated as an abstract relationship between bright and dark, but as a concrete value expressed in nits. A 600-nit signal defined by the creator is meant to be reproduced as 600 nits in front of the viewer.

Source: Dolby ICC HDR Experts Day – Real-world luminance and the range of human visual perception.

The goal of this system is to make different monitors output light at the same physical intensity when given the same signal. In reality, however, many displays cannot fully reproduce this luminance range. As a result, even within the HDR standard, differences in brightness from one display to another remain unresolved. Colorists are still left worrying about device-specific variation rather than focusing entirely on the message of the scene.

Dolby Vision: A Systematic Separation of Intent and Output

Dolby Vision emerged as one response to that limitation. Its core idea is the systematic separation of the creative environment from the playback environment. A Dolby Vision master carries metadata describing the monitor on which the colorist worked. During playback, the system uses that information together with the characteristics of the target display to determine how the final image should be rendered. The system calculates and bridges the gap between the original image and the actual output.

Source: Dolby – ‘The Role of Dolby Vision Metadata’

This structure allows the colorist to focus more fully on the work itself. Concerns about how the image will appear on a specific display can be handed over to the system, making it possible to return to scene-based grading. Time and energy once spent predicting and compromising around device-dependent outcomes can instead be redirected toward creative decisions. That is why Dolby Vision has always meant more to me than simple image enhancement.

Dolby Vision 2: Completing the Ecosystem by Accounting for the Viewing Environment

The latest Dolby Vision 2 extends that management one step further. It brings the real-world viewing environment itself into the system’s scope of control. One of HDR’s persistent weaknesses comes directly from its reliance on absolute luminance. The same image can feel completely different in a dark theater and a bright living room, in both contrast and color. No matter how precisely light is reproduced in absolute terms, the human eye perceives it differently depending on the ambient light level and color temperature of the viewing environment.

Source: Dolby – ‘Dolby Vision 2’

Dolby Vision 2 addresses this by gathering two types of information.

The first is information about the creative environment. The brightness and color temperature of the grading room are recorded as metadata along with the image.

The second is information about the viewing environment. An ambient light sensor built into the playback device detects the brightness and color temperature of the viewing space in real time.

The system calculates the difference between these two environments, estimates how the viewer’s eyes are adapted to the current conditions, and adjusts contrast and color accordingly. It is not simply raising or lowering physical brightness. It is calculating how the scene should be perceived in this specific space. As a result, even when the viewing environment changes, the underlying tone of the scene can remain intact. What SDR left entirely to the viewer’s eyes is now taken over by the system.

Toward a More Precise Image Ecosystem

The progression from SDR to Dolby Vision 2 was never simply about making images “brighter and sharper.” At its core, this technological shift reflects a change in how we think about light. Should image reproduction rely on human adaptation? Should it be quantified through absolute values? Or should the system go further and account for both the viewing environment and the viewer’s perceptual state? The path from SDR to HDR and then to Dolby Vision is, in many ways, a continuing history of questioning where responsibility for image interpretation should reside.

In this process, not only Dolby Vision, but also a range of other HDR technologies, including HDR10+, have been developed toward the same goal. I plan to continue the discussion of those other HDR technologies in the next post.

Whatever the technology may be, once we understand it and work within its ecosystem, we can step away from the exhausting task of compensating for image differences device by device. That part can be left to the system. Then we can return to what matters most: the scene itself, and the grading decisions it calls for. At that point, “diverse viewing environments” no longer need to be treated as a source of anxiety, but as multiple spaces through which the content can meaningfully extend its reach.

Alongside this project, you can explore more of CAPRA’s work on instagram **@capra.official.colour / @capra.official or on [our official website](http://capra.life)**.