EXR Technology: Wide Dynamic Range

Expansion of Dynamic Range, More than Ever

Like the human eye, accurately discerning light and dark in places with contrast.

For Richer Gradation Expression

The Super CCD EXR realizes further expansion of the dynamic range*1 and enables a more ample gradation expression. Generally, when attempting to adjust exposure for a dark location, a “washout” condition occurs as the gradation of light areas is lost. Conversely, when attempting to adjust exposure for a bright location, a “blackout” condition occurs as the gradation of dark areas is lost.

Technology that Extracts Two Images

To solve these problems, “Dual Exposure Control” technology was adopted. A single shutter click extracts two images—one at high sensitivity (Side A) and the other at low sensitivity (Side B) by electrically controlling the exposure time for each image. Optimally combining the two images, reproduction of an image with both light and dark places of vividness was successfully produced. Furthermore, it is theoretically said that by adjusting the exposure time of Side B to 1/8 and 1/16, it is possible to expand dynamic range by 8 and 16 times to that of the conventional factors.

1: Equivalent to image taken at high sensitivity 2: Equivalent to image taken at low sensitivity 3: Two patterns are optimally merged to create a photo with extended dynamic range.
1: Dynamic Range

“EXR Method” for Wider Dynamic Range

Until now, Fujifilm has adopted two methods in an attempt to expand dynamic range. One was the SR method which employed a “double pixel structure” comprised of “S pixels” with a large area and high sensitivity and “R pixels” with a small area and low sensitivity. This realized a dynamic range approximately 4 times to that of conventional methods.
The other known as the HR method, involved shooting under conditions in which “washout” would not occur, increasing sensitivity through signal processing, adjusting shadow gradation, softening highlights, and depicting an optimal curve. However, it was difficult for the SR method to achieve further expansion of dynamic range because of technical problems. With the HR method, noise increased when dynamic range was expanded. As a result, by merging the advantages of the two methods, the “EXR method” has made dramatic advances.

Notes
  • Dynamic range: Signal ratio between the maximum and minimum measurable light intensities.