Dynamic Tone Mapping: Making HDR Projection More Realistic and True to Creative Intent

As HDR technology becomes widespread, home cinema projector users increasingly expect contrast and detail that rival high-end televisions. However, projectors have inherent brightness limitations, making accurate High Dynamic Range (HDR) presentation a technical challenge. Dynamic Tone Mapping (DTM) is an innovative approach adopted by leading projector brands, including BenQ, to overcome this barrier.

Tone mapping is the process of compressing HDR signals—often exceeding the brightness range of display devices—into what a projector or display can actually show. Under the SDR (Standard Dynamic Range) standard, both signal brightness and display brightness are defined using a relative scale (percentage-based). The image is transformed according to a gamma curve, without an absolute peak brightness limit. In practice, SDR content is typically designed for a reference brightness level of around 100 nits. In contrast, HDR standards use absolute brightness, with peaks reaching up to 10,000 nits. In today’s market, most content falls between 1,000–4,000 nits, though HDR10 content can go as high as 10,000 nits.

Since projectors typically cannot directly reproduce these extreme brightness levels, a well-designed tone mapping curve is critical to decide which highlights and shadow details are preserved. However, static tone mapping typically applies a single fixed curve, imposing limitations on faithfully reproducing the full brightness and contrast of HDR content.

Static tone mapping compresses high-brightness HDR content into the limited brightness range of projectors—typically below 500 nits—using a single, fixed tone curve. This means that whether the scene is bright or dark, the same mapping approach is applied.

The consequence is that if the mapping curve favors brightness, the shadows become crushed, and important dark details are lost. On the other hand, if the curve favors shadows, the highlights become flattened, washing out the bright details. This delicate balance means that static tone mapping forces a compromise, sacrificing either the bright or dark portions of the image depending on the tuning.

Manufacturers have typically relied on subjective tuning, selecting a balance that looks “most acceptable,” but ultimately, this compromises the creator’s original intent.

Dynamic Tone Mapping dynamically adjusts the tone mapping curve on a frame-by-frame basis, adapting to the unique brightness distribution of HDR video content (HDR10 format).

This enables:

• Bright scenes: Pulling out highlights like skies, clouds, and fine bright details.
• Dark scenes: Preserving shadow textures and low-light nuances.
• Full use of the projector’s brightness potential without tradeoffs.
• A picture much closer to the creator’s original artistic vision.

For BenQ, Dynamic Tone Mapping plays a vital role within their HDR optimization suites HDR-PRO™, complementing other features such as Local Contrast Enhancer, Global Contrast Enhancer, and Dynamic Black for an even more refined result.

What is BenQ HDR-PRO™ Technology?

This demonstrates how DTM transforms HDR performance, letting projectors punch far above their hardware limits.

Dynamic Tone Mapping is not just about making the image “brighter” or “darker”—it’s about precise, frame-by-frame analysis and adjustment that preserves both highlight and shadow detail. By maximizing every bit of projector capability, DTM pushes HDR performance to new heights, delivering an unparalleled level of realism and immersion.

For home cinema enthusiasts, BenQ’s premium projectors like the W4100i and W5850 come equipped with Dynamic Tone Mapping, offering advanced HDR tone optimization. These models combine 4K resolution, wide color gamut, and DTM to ensure that whether watching HDR movies or premium video content, users experience rich contrast, stunning detail, and professional-grade home theater performance.