Digital Prints

94
Mastering Digital Printing
While the debate continues over whether film or digital is better for the highest-quality
imaging and printing (many feel that digital equals or exceeds 35mm quality but film still
wins in larger formats), capturing images with either a digital-capable camera or a digital
camera back continues as a growing trend.
What You Need to Know about Digital Cameras
Using lenses to focus light and create an image in the same way film cameras do, digital
cameras or “digicams” are basically little scanners, and all the things we’ve learned about
pixels, file sizes, and resolution apply here equally as well (i.e., more is better). The main
difference is that the cameras in this category are primarily “area array” devices. A single,
light-sensitive sensor (CCD or CMOS), which is made up of tiny elements in a checkerboard
or mosaic pattern that are individually coated to be sensitive to red, green, or blue
light, is exposed through a lens to the light reflecting off the subject. The camera converts
the analog signal into binary information, and bingo, you have a digital file.
Everyone thought that the revolutionary Foveon X3 image sensor (introduced in 2002)
would change the digital camera industry forever, but with only Sigma and more recently
Polaroid offering Foveon sensors in their cameras, it just hasn’t happened (yet). Instead of
sensing elements that capture only one color at a time, each Foveon chip has three photo
detector layers to capture a different color—one each for red, green, and blue (see Figure
3.12). As a light ray sinks into the sensor, first blue, then green, then red is absorbed. So,
what’s the big deal? The resulting image can be sharper and with higher resolution.
Digicams come in myriad styles and types. Pick up a photography magazine or walk into
any camera store, and you’ll see that there are point-and-shoots, “prosumer,” professional,
and studio cameras for every possible use and occasion. They are usually categorized and
marketed by their maximum number of recorded pixels, e.g., 2048 × 1536 (that’s horizontal
by vertical). This is the advertised CCD resolution, which is arrived at by simply multiplying
the two numbers together and rounding off to the closest million-pixel decimal. For
example, 2560 × 1920 pixels equals 4.9 or just 5 Megapixels (abbreviated as 5 MP).
A 5-MP camera is considered to be the minimum for capturing images that can yield
decent quality at moderate print dimensions. Consider a 5.1-Megapixel camera like the
Nikon Coolpix 5700 that has a maximum resolution of 2592 × 1944 pixels. An opened
Figure 3.12 Two digital camera sensor
technologies—left: a small 2 Megapixel
CCD sensor and a simulated area array
pattern of the individual elements; right:
the newer Foveon X3 layered chip.
right: © 1998-2002 Foveon, Inc.