206 Glossary
DVD Digital video disc. Unlike the 600+MB capacity of CD-
ROM discs, a DVD can store 4.7GB or more on a single disc
that is the same physical size. Although competing formats exists
for writable DVDs, this has not stopped a number of companies
from installing writable-DVD drives in computers or offering
them as external peripherals. It is just a matter of time before
the DVD format replaces all disc-based data media, including
CD-ROM and music CDs too.Dynamic range Can be interpreted as the range of f-stops that
can be captured from a print or slide. Rated on a scale from zero
to 4—where 0 is a clean white and 4 is total black. Photo -
graphers may recognize these as the zones that Ansel Adams
called Zones IX and 0 in his Zone System. The maximum- and
minimum-density values capable of being captured by a specifi c
scanner are sometimes called dMax and dMin. If a scanner’s
dMin were 0.3 and its dMax were 3.5, its dynamic range would
be 3.2.EI Exposure index. The rating at which a photographer actu-
ally exposes a specifi c kind of fi lm, therefore deliberately under-
exposing or overexposing it. This is accomplished by changing
the camera or handheld meter’s ISO fi lm speed to refl ect a
number different from that recommended by the manufacturer.
E-TTL Evaluative Through-the-Lens fl ash-exposure metering
used by Canon EOS fi lm and digital cameras.EV Exposure value. Numeric value to describe the exposure
where a variety of shutter speed/aperture combinations produce
the same exposure with a constant fi lm speed. For example,
1/250s + f/2.0 = 1/125s + f/2.8 = 1/60s + f/4.0 = 1/30s + f/5.6 =
1/15s + f/8.0, and so on. (This is different from the exposure
index.)
FAQ Frequently Asked Questions. Term found on Internet
home pages, leading you to an area containing answers to ques-
tions that visitors to the Web site might have.Fractal Graphics term originally defi ned by mathematician
Benoit Mandelbrot to describe a category of geometric shapes
characterized by an irregularity in shape and design. Used by
computer software, such as Lizard Tech’s Genuine Fractals
(www.lizardtech.com), as a mathematical model for resizing and
enlarging image fi les.
Gamma Measurement of the contrast that affects mid-tones in
an image. One of the differences between Mac OS and Microsoft
Windows operating systems is that they have different basic
Gamma settings. For a Windows computer, it’s 2.2, whereas
Gamma is 1.8 on a Mac OS computer—which is why images that
look fi ne on a Mac appear darker on a Windows computer.