Archive for October, 2021

It’s A Matte of Scale

Sunday, October 24th, 2021

Grayscale
Accurate luminance reproduction precisely ascends and scales, from absolute black to specified white light.  It’s a scale or grayscale that generates accurate colors, much as audio frequency response generates musical timbre.  The grayscale is a prerequisite for high-performance HDR UltraHD video reproduction.

Contrast
The contrast ratio is the difference between the brightest and darkest screen images.  The difference establishes the dynamic range of luminance plus shades of color, much as the dynamic range of an audio system that recreates shades of harmonic detail to the concussive exploding sound.

There are two types of contrast ratio measurement — dynamic and ANSI static.

Dynamic
The contrast ratio is the most quoted by manufacturers, e-zines, and magazines.  Dynamic contrast refers to the deepest black versus the brightness white that a television, studio monitor, projector/screen can display.  But not at the same time.  Dynamic contrast is an all-on versus all-off test.  This simple test can generate impressive numbers such as 20,000:1 or much higher. But not necessarily impressive video.

ANSI Static
The ANSI static contrast ratio uses a standardized checkerboard test pattern of black and white rectangles.  The ANSI standard simultaneously measures the difference between the darkest black and brightest white displayed side by side on the screen.  This spec more accurately predicts potential performance.

Key Point
Grayscale and dynamic range are baseline specs.  They set the table for high-performance HDR UltraHD home theater video reproduction.

For more information, select this link … Ed’s AV Handbook chapter 4 page 8