Datasheet

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CHAPTER 1 : BEFORE YOU SHOOT ■
sensors less meaningful. (Read more about this in the “Zooming In” appendix under
“Sensors Expanded.”) Sometimes the documented number of pixels may include pixels
that aren’t even actively used, introducing yet another variable.
Some of the earliest digital cameras captured only 640
× 480 pixels (.3 megapix-
els)—just enough pixels to fill a small computer monitor, and barely enough to produce
a decent 3"
× 4" print. Nowadays a typical 5-megapixel consumer digital camera cap-
tures around 2576
× 1932 pixels, which is plenty enough resolution to produce a
decent 11"
× 14" print. Table 1.1 shows what size prints you can reasonably expect to
produce from various resolutions. Note that these are general guidelines and actual
results will vary depending on the type of digital camera and output device used and
other qualities of an image such as sharpness, color, and content.
Table 1.1: Optimal pixel resolutions needed for desired output specifications (assuming
200 dpi print resolution)
Note: Roughly speaking, it requires a digital camera capable of capturing approximately 6
megapixels to match the print quality produced with medium-grain 35mm film. Other digital
camera variables such as lens quality, sensor characteristics, and image-processing capabili-
ties make a difference as well.
Considering Exposure Latitude
Most point-and-shoot digital cameras pack lots of pixels into physically small sensors
with a trade-off in quality. Exposure latitude between light and dark, for example, may
not be nearly as good as film provides. Low-light situations may result in extremely
“noisy” images. On the other hand, digital single lens reflex (SLR) cameras generally
use larger sensors with better exposure latitude and low-light capabilities. Why do larg-
er sensors give better latitude? Larger sensors (in general) have larger photo receptors
for each pixel and can capture more light and generate more photo electrons. In addi-
tion, all sensors have some level of electronic noise.
In subsequent chapters I’ll get more into the subject of extending exposure lati-
tude and shooting successfully in low-light situations.
Bottom line: Unlike film cameras, digital cameras depend on a complex array of electronic
components, all of which contribute to image quality—or lack thereof.
3'' × 5''
5'' × 7''
8'' × 10''
11'' × 14''
16'' × 20''
.6 megapixels (900 × 675 pixels)
1.3 megapixels (1280 × 960 pixels)
3.2 megapixels (2048 × 1536 pixels)
6.1 megapixels (3008 × 2000 pixels)
11 megapixels (4064 × 2704 pixels)
Print Size (inches)
Need at least
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