MELTED BOKEH

MELTED BOKEH｜渐融焦外

Creating Stronger Visual Separation Between Focus and Defocus

The most distinctive visual language of MUSE PRIME is Melted Bokeh｜渐融焦外, an approach to image character developed by ELYSAS.

At its core, Melted Bokeh is about creating stronger visual separation between what is in focus and what falls out of focus.

We believe that subject presence and spatial depth are never determined by a single optical metric. They emerge from the relationship between the plane of focus, defocus in front of and behind it, and the way rendering changes from the image center to the periphery—across resolution, contrast, residual aberrations, and blur structure.

For this reason, in-focus MTF is not the sole optimization target in the optical design of MUSE PRIME.

We quantify in-focus resolving power, contrast, and residual aberrations while also evaluating how aberrations and blur structure evolve at multiple positions in front of and behind focus. Across the image field, we analyze sagittal and tangential behavior at different image heights, together with changes in resolution, contrast, and defocus rendering.

By treating the plane of focus, front and rear defocus, and center-to-periphery behavior as one coordinated system, we can shape the relationship between focus and defocus across the entire frame.

Melted Bokeh is therefore not a fixed bokeh shape, nor is it simply an attempt to make backgrounds softer or more blurred. In selected areas of the defocus, a slight tendency toward double-line bokeh may be deliberately retained. Similar behavior can be found in some vintage lenses, where modest peak MTF can coexist with strong subject separation and distinctive depth rendering.

MUSE PRIME uses controlled changes in aberration, contrast, and blur structure across different defocus positions and image heights to strengthen the distinction between focus and defocus without breaking the spatial relationship between subject, foreground, background, and environment.

The background retains form, texture, and spatial context, while the subject separates more clearly from its surroundings. Melted Bokeh does not pursue more blur for its own sake. It pursues more effective separation—preserving the environment while guiding the viewer’s attention naturally toward the subject.

FIVE-ZONE IMAGE EVALUATION

Five-Zone Image Evaluation

Describing Lens Behavior Across Defocus and Image Height

Five-Zone Image Evaluation is a multidimensional image-evaluation method developed by ELYSAS to describe how lens rendering changes along two directions: through focus and across the image field.

The five evaluation zones are:

Front Defocus · Plane of Focus · Rear Defocus · Image Center · Image Periphery

Front defocus, the plane of focus, and rear defocus describe how rendering changes with defocus position. The image center and periphery describe how performance changes at different image heights.

Within each zone, we analyze modulation transfer function (MTF), residual aberrations, sagittal and tangential behavior, defocus blur structure, and the way these characteristics evolve. We then compare their continuous change through focus and across image height.

Performance at the working distances most relevant to each focal length is also optimized separately.

The purpose of Five-Zone Image Evaluation is not to maximize a single metric at a single position. Instead, it establishes quantitative constraints that describe the relationships between focus and defocus, and between the center and periphery, and incorporates those constraints directly into optical optimization.

This provides the optical foundation for the visual separation created by Melted Bokeh｜渐融焦外.

IMAGE RELATIONSHIP

Image Character Is Defined by Relationships

Five-Zone Image Evaluation can be used to analyze any lens. Melted Bokeh considers not simply how blurred a background becomes, but how rendering differs between focus and defocus—and how those differences evolve with subject distance and the amount of defocus.

Even when peak MTF is not exceptionally high, the right relationship in resolution, contrast, and residual aberrations between focused and defocused areas can still create pronounced subject separation and a convincing sense of dimensionality.

For MUSE PRIME, defocus is not simply an area that has lost sharpness. It has its own image structure, shaped by residual aberrations, changing resolution, local contrast, and blur behavior. Together with the in-focus image, these characteristics shape space, guide attention, and establish visual hierarchy within the frame.

FOCUS TO DEFOCUS

A Continuous Transition from Focus to Defocus

As the image moves away from the plane of focus into front and rear defocus, resolution, contrast, and aberration balance change in a controlled, continuous progression. This strengthens the distinction between focus and defocus without breaking the natural spatial continuity of the image.

MUSE PRIME night scene transitioning continuously from focus into Melted Bokeh

SPATIAL DEPTH / 3D POP

Spatial Depth and 3D Pop

This controlled progression from focus into defocus gives a two-dimensional image a more natural sense of depth and dimensionality. It reinforces what cinematographers often describe as “3D pop,” without relying on low overall resolution or broad compromises in image quality.

DESIGNED FOR STORY

Designed for Story

A Coherent Image Language

MUSE PRIME was never conceived as a set of unrelated focal lengths. It was developed as a complete imaging system built around a consistent set of aesthetic targets and evaluation standards.

Every focal length follows the same approach to color, overall contrast, resolving character, focus falloff, aberration behavior through focus, and rendering from the image center to the periphery.

Whether a wide lens establishes the environment, a normal focal length brings the viewer closer to a character, or a longer lens concentrates attention on performance, MUSE PRIME maintains a coherent language of color, contrast, and defocus, together with consistent, subtly warm, natural-looking skin tones.

Cinematographers can choose focal lengths according to the needs of the story without obvious shifts in rendering from lens to lens disrupting the visual continuity of a scene or sequence.