46 Better Available Light Digital Photography
With normal image capture, when
the dynamic range of that scene is
too great for any part of the digital
capture process, something’s gotta
go; you have to choose between
losing detail in the shadows or the
highlights. These are the three
image fi les that were used to make
the composite HDR image (High
Dynamic Range). © 2007 Joe
Farace.
This photograph, made in the morning at Barr Lake in Colorado, has an extreme dynamic range ranging from
a “bald-headed” sky in the background to inky shadows in the foreground. It was one of 12 exposures made,
and was the one in the middle (1/60 at f/10 at ISO 100) of the bracketed series. © 2007 Joe Farace.
how do you represent the light values in a scene using a limited
set of light values? HDR (High Dynamic Range) is a buzzword
that’s gaining in popularity for digital imagers, and just might
hold the answer. The concept behind HDR is the ability to use
a technique that can create an image whose overall tone values
match the luminance of what the human eye records, not what
a computer screen or print reproduces. Luminance is the bright-
ness, or grayscale level, of a color. Together with chromaticity,
luminance defi nes a perceived color.