Summer,
as always, is a blur of activity, and is gone too quickly! There
never seems to be enough time to simply sit back and enjoy the
warm breezes in the company of friends. An exception for me is my annual college "suite"
mates reunion which I host every August in Jamestown, RI. It's
a weekend to reflect on friendships that have stood the (30 year) test of
time, catch up on what challenges and adventures have shaped our lives this past year, and most importantly, look forward to doing it all
again next year!
The commemorative teeshirt (shown at left), includes this years
"Free-Tee" contest winner, a haiku by Maureen Wolf, "Mermaids
rise again ~ they surface once a year ~ but never leave our hearts".
I hope you all had a great summer, and took the time to enjoy your family and friends!, Debi
.:TECH TIP:
Vector vs. Bitmap
Some of you have probably sent a JPG or GIF of your logo to a designer for use in a printed piece and
immediately gotten a call asking if you have it as vector art. You likely responded with "what is vector art?". So here it goes...
Vector art is created in vector software such as Macromedia Freehand
and Flash, CorelDraw, or Adobe Illustrator. In these programs, lines and curves are rendered
using mathematical definitions. When a vector image is scaled, the paths are regenerated which allows it to be infinitely scalable without degradation.
Bitmaps on the other hand are images formed by individual squares of colors called pixels (short for picture elements).
The human eye is not capable of seeing each individual pixel so we perceive a picture with smooth gradations.
The number of pixels you need to get a realistic looking image depends on the way the image will be used. Websites or other images viewed on your computer monitor use 72 pixels per inch, whereas
offset printing requires a minimum of 300. The problem lies in how a bitmap renders a curve. Unlike vector
art where a black circle on a white field has a smooth edge, an enlarged bitmap has a steppy or jagged appearance.
You can create the illusion of a smooth curve in a bitmap with antialiasing, where varying shades of gray
(in this example) fill in between the black and white areas. Bitmaps are fine as long as you don't enlarge them, but once you do you'll see the pixel steps or gray pixels around curves.
In short, Graphic images such as logos are best created in a vector
program and saved as an .EPS (encapsulated post script). Photos and
images with smooth graduations are best represented in bitmap form.
Finally, a word of warning, if you open vector art in a bitmap program
such as Photoshop, the image is rasterized into a bitmap, where it
can also be saved as an .EPS, however the resulting file has now become
a bitmap and should not be enlarged above it's saved size. I demonstrate this in the image to the left, however as this emailer
is web-based you are looking at vector art which has in fact been
rasterized :-)
