UNITS OF MEASUREMENT 2.01 Understand Digital Raster
Graphics
Slide 2
What Unit of Measurement to Use Quiz Question: List as many
units of measurement that you can think of as a class. Inches
Pixels Points Picas Did you have more than one from the list below?
We generally pick what we are comfortable with, but in Graphic
Design it should be based on need.
Slide 3
Inches The standard unit of measurement for the United States
and U.S. standard sized papers. What is 8.5 x 11 called? 11 x 14?
11 x 17? Letter, Legal, and Tabloid Letter size is standard for
most printers, resumes, and other common documents. Works well when
defining document sizes for print. What most of us are comfortable
with.
Slide 4
Pixels The most common unit of measurement for computer screen
display. Generally represented by one dot that is illuminated on a
computer screen. Many pixels make up an image or images. A precise
measurement system for web-design. Lacks flexibility as screen
sizes change.
Slide 5
Points The standard unit of measurement for typefaces. 1 point
represents 1/72 of an inch. Therefore text formatted with a font
size of 72 pt is about one inch. However, variations occur due to
font designs. Standard size for print paragraphs = 12 pt (
Generally)
Slide 6
Picas Quiz time: What is 11 inches divided by 3? Quiz time,
part two: What is 72 divided by 3? One pica equals 1/6 of an inch.
Six picas per inch. Often used in print design, since it is easily
divisible. Picas work well when applying the Rule of Thirds.
Slide 7
IMAGE RESOLUTION AND COLOR MODE
Slide 8
Begin with the End When talking about image resolution and
color mode to choose when designing, you have to think about what
the desired output will be. Web? Or Print?
Slide 9
What is resolution? Resolution is a measure of the amount of
detail that is stored in a digital image. Higher resolution means
higher quality. But is high resolution always a good thing. Lower
resolution means lower quality. But is lower resolution always a
bad thing.
Slide 10
Resolution is measured in PPI, or pixels per inch (the number
of pixels contained in one inch). The higher the PPI, the better
the quality. The higher the PPI, the larger the file size. Image
editing software can be used to change the resolution of an image.
Image Resolution
Slide 11
Images can be viewed in two ways On a screen or monitor or by
printing it on paper Monitors Monitors are low resolution devices,
most display 72 ppi. Additional image resolution will increase file
size, without affecting display quality. Printers The resolution at
which printers can print is measured in Dots Per Inch (DPI).
Printers are high resolution devices and require high resolution
images in order to print images clearly without pixelation or
blurriness. Image Output Methods
Slide 12
Images that will be displayed on a monitor do not need a high
resolution. Using a low resolution means smaller file sizes. Images
with small file sizes load quicker. Images that will be printed
need a higher resolution. Images with 300 PPI are better for
printing on more sophisticated printers and will produce
higher-quality photographs. Match The Image Quality To The Delivery
Method
Slide 13
Color Modes: a mathematical model that describes the way colors
can be represented as numbers or percentages, typically with three
or four values. There are many types of color modes, but generally
you will work with two when editing raster images. RGB Color CMYK
Color What About Color Mode?
Slide 14
RGB: assigns an intensity value to each pixel ranging from 0 to
255 for each of the red, green, and blue components in an image. If
all RGB values are 0, you get black. If all RGB values are 255, you
get white. On-screen display is represented by RGB, therefore RGB
color is best used for images that will be displayed on a monitor
or webpage. RGB Color
Slide 15
CMYK: assigns a percentage value for each of the process inks.
Cyan, magenta, yellow, and black. If all percentages are set to 0,
the result is white. If all percentages are set to 100, the result
is black. An image should be converted to CMYK before exporting for
images that will be sent to print. CMYK Color
Slide 16
An image is being designed that will be display on the new
company website. What color mode and what resolution should the
image have? RGB color and 72 ppi. A poster is being created that
will have 500 copies printed to promote the upcoming concert. What
color mode and resolution? CMYK color and 300 ppi. Quiz Time