1. Graphics Basics
Ellen Eyth

2. What are Graphics? Chart Drawing Painting Photograph Logo
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Diagram

3. Image Editing Images edited on a computer are either:
BITMAPPED GRAPHICS (Photoshop, Corel Draw, etc,)
VECTOR GRAPHICS (Illustrator, InDesign, etc.)

4. What are “Bitmapped” Graphics?
Bitmapped graphics consist of grids of tiny dots called PIXELS. Each pixel is assigned a color. AKA Raster Graphics
Can be in full color or gray
Photo editing programs such as Photoshop are pixel based.
If you zoom in REALLY far on your image in PS, you will find tiny squares of color. Enlarging bitmapped images may compromise clarity or “crispness”.

5. What are “VECTOR” graphics?
Use mathematical formulas to define points, lines, curves, and other attributes.
Vector editors are called DRAW PROGRAMS. (Illustrator)
They will never lose clarity as they are enlarged or decreased in size.
They are good for making logos, printed signs, banners, and other large format graphics.

6. Graphics Quality Resolution (dpi) and Color Depth
2 factors that determine graphic quality- Resolution and color depth.
Resolution is determined by the number of pixels per inch (ppi) or dots per inch (dpi).
Color depth refers to the number of distinct colors an image can contain. It can range from 2-bit (black and white) to 24-bit which has 16.7 million colors.
8-bit has 256 colors (called INDEX color).

7. File Formats- Common formats:
GIF (Graphics Interchange Format)
JPEG (Joint Photographic Experts Group)
TIFF (Tagged Information File Format)
PNG (Portable Networks Graphics)
BMP (bitmap)
TGA (Targa)
The most common format for editing and viewing photos is JPEG.

8. Resolution Resolution is how sharp or clear the image appears.
Low resolution appears blurry or pixelated.
High resolution is clear and sharp but the image is larger in file size.
Screen resolution- Anything you see online- 72 dpi
Print resolution- needed for high quality print jobs – 300 dpi