Wednesday, August 15, 2012

So, What exactly is a vector?

So, What exactly is a vector?????
It is one thing to read about the differences between Vector and Raster Art but true clarity comes when we see these differences.

To re-cap from my earlier post a vector drawing can be described as a clean, visual composition that can be scaled without losing resolution.  Vector art is great for creating wireframes, logos, icons, complex shapes, setting type and so much more.

Illustrator is Adobe's Vector Drawing software that integrates beautifully with Adobe's other Programs (Photoshop, InDesign, Flash, AfterEffects, etc). 

Whereas Illustrator is a Vector based program, Adobe Photoshop is raster imaging software.  When working with raster images we are limited by pixels and resolution.  We constantly have to watch the DPI (dots per inch) or the PPI (Pixels Per Inch) settings .  There are places where raster imaging is exactly what we want.  Pixels are perfect for photos.  A concentration of colored pixels is what creates a digital photograph. 
(One thing to keep in mind is that sometimes you will have to take a vector image and turn it into a raster if you are taking that image to the web, a mobile device or an e-tablet.)  

Now let's look at some examples!
Example 1: Vector Logo on Left, Raster Logo on Right

In the above example, Example 1, we see a Vector Graphic on the Left and a Raster Graphic on the right.  Upon first glance the two images don't look much different.  Now let's zoom in to see the differences!

Example 2:  Zoomed in Raster Image
In Example 2 the differences become clear.  Our raster image is based on pixels.  When we zoom in we see these pixels.

So, when we work with our raster images we have to continually watch the resolution.  The more pixels an image has the higher the resolution.  The higher the resolution the larger the file.

When working with raster images if we are going to print the image we usually work at a higher resolution.  This resolution is often set to 300 ppi (pixels per inch).   When we are preparing an image to be used on the web we often work at a lower resolution such as 72 ppi (pixels per inch).  One of the reasons why we work at a lower resolution when we are preparing an image for the web is so the file size is smaller and will not slow down the person's internet connection as he or she waits for it to download.

Example 3: Zoomed in Vector Image

In Example 3 we see what happens when we zoom in on our Vector Image.  This graphic is not based on pixels.  Instead, underlying the shapes, colors, and type are mathematical equations, making this graphic resolution independent.

We could describe the edges of this image as being crisp and clear. 

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