DOTS PER INCH - PIXELS PER INCH - RESOLUTION
What does that mean?
A digital piece of equipment, like
a monitor, for instance has a resolution of say 800x600
pixels. What does that mean? For example, a
pixel is comprised of 3 bytes, that's small. In fact,
it is the smallest type of measurement of an image.
Scanning a photo is measured in PPI (pixels per inch).
Allot of small pixels make up an image. A
pixel's size is 3 bytes, too small to measure on a ruler.
Therefore, a 3 Megapixel photo for instance, is 9 Million
Bytes or 9MB in file size.
When you scan a 4x6"
photo at 300 ppi
your get 1200x1800
pixels. The
more pixels a image
has the more fine
detail is seen.
Therefore,
more Resolution
means better
quality.
What
about resolution and
printing?
Knowing about
resolution is very
important when
determining printing
size.
The standard
ink-jet printers print
at 300 dots per inch, or
dpi, a similar concept
to "Pixels
per Inch or ppi".
The more pixels (of a
fixed size) a image has,
the more you can "blow
up" or enlarge a picture
and not loose the fine
detail. What that
means is if you want
high quality pictures
when printing large,
then you should scan at
a Higher Resolution to
obtain that detail.
In
other words, high
resolution lets you
"zoom in" and still
retain the quality when
printing. The
bottom line is go for
higher resolution when
scanning.
Examples of different
resolutions
Here
is the same image
scanned at different
resolutions .
The one on the left is
of higher resolution
(600dpi)
than the one on the
right (300dpi). When
scanning, go for the
higher resolution, more
dpi's are a good thing.
