Introduction

A lion's share of the industry standards for graphic design, video editing and web development is comprised of Adobe Systems products. The workflows produced by their software are heavily integrated into the training of the creative workforce today, spanning their influence over raster, vector, static and dynamic assets across all platforms.

Image Types

Fundamentally, computer graphics are encoded in two ways: as colored cells (Raster) or geometry (Vector). The image formats we are familiar are rasters which vary in their packaging, either uncompressed or compressed, in order to reduce the file size by leveraging the redundancy in the image's content.

Rasters

Raster graphics are bitmaps, or a grid of individual pixels that collectively compose an image. Raster graphics render images as a collection of countless tiny squares. Each square, or pixel, is coded in a specific hue or shade.

Because raster images are pixel-based, they are subject to image degradation. Just like photographic images that get blurry and imprecise when blown up, a raster image gets jagged and rough (See aliasing). This ultimately is because when a raster graphic is created at a certain size, it has a fixed number of pixels that comprise the image. Hence an image attempting to scale an image up by 100 it will become bitmapped. Likewise, scaling an image down, although usually is easier to achieve, does in fact degrade an image as well with detail becoming softer than the original, at its created size.

To maximize the quality of a raster image, you must keep in mind that the raster format is resolution-specific. Raster images are defined and displayed at one specific resolution. Resolution in raster graphics is measured in dpi, or dots per inch. The higher the dpi, the better the resolution. Remember also that the resolution you actually observe on any output device is not a function of the file’s own internal specifications, but the output capacity of the device itself. Thus, high resolution images should only be used if your equipment has the capability to display them at high resolution.

Better resolution, however, is directly correlated to file size. Just as raster files are significantly larger than comparable vector files, high resolution raster files are significantly larger than low resolution raster files since the computer needs to store information on every single pixel.

Vectors

Unlike pixel-based raster images, Vector graphics are based on mathematical formulas that define geometric primitives such as polygons, lines, curves, circles and rectangles through translation into points, a start and end, connected by vector paths.

Because vector graphics are composed of true geometric primitives, they are best used to represent more structured images, like line art graphics with flat, uniform colors. Most created images (as opposed to natural images) meet these specifications, including logos, letterhead, and fonts.

Inherently, vector-based graphics are more malleable than raster images — thus, they are much more versatile, flexible and easy to use. The most obvious advantage of vector images over raster graphics is that vector images are quickly and perfectly scalable because they are comprised of dots and vector paths. There is no upper or lower limit for resizing vector images, resulting in no sacrifice of image quality regardless of scale from a note card to a billboard. The edges of each object within the graphic will always stay smooth, crisp and clean. Just as the rules of mathematics apply identically to computations involving two-digit numbers or two-hundred-digit numbers, the formulas that govern the rendering of vector images apply identically to graphics of any size.

Further, unlike raster graphics, vector images are not resolution-dependent. Vector images have no fixed intrinsic resolution, rather they display at the resolution capability of whatever output device (monitor, printer) is rendering them. Also, because vector graphics need not memorize the contents of millions of tiny pixels, these files tend to be considerably smaller than their raster counterparts. Overall, vector graphics are more efficient and versatile.

Common vector file formats include AI, EPS, SVG, XML, CGM and PICT (Mac).

Use Cases

File size is important to take into consideration. If a smaller file size is what you’re looking for, stick with vector graphics.

Raster graphics and raster editing are optimal for non-line art images; specifically digitized photographs, scanned artwork or detailed graphics. Non-line art images are best represented in raster form because these typically include subtle chromatic gradations, undefined lines and shapes, and complex composition. Additionally raster graphics are able to portray better color depth. Each pixel can be any one of the 16 million different colors available.

Overall, as compared to vector graphics, raster graphics are less economical, slower to display and print, less versatile and more unwieldy to work with. Despite its shortcomings, raster format is still the Web and Image standard as, like photographs, they are still best displayed in raster format.

But, if you’re not working with digital photographs, Vector graphics editors would be ideal for all other types of design editing, especially because vector graphics are able to be scaled and manipulated at any size with clarity.

File size is important to take into consideration. If a smaller file size is what you’re looking for, stick with vector graphics. Raster image files can be quite large since the computer needs to remember information about every single pixel.

Static and Dynamic Content

Overarchingly the additional spectrum that can be applied to Adobe Software is its ability or platform forte to deal with static or dynamic content. Primer, Flash and Aftereffects in this aspect would define one end of the spectrum while Illustrator and Indesign would occupy the opposing end. This distinction specifically denotes content creation as opposed to management tools

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Spectrum define core 10 approx Adobe software
Place from content / asset management and creation - static to dynamic

The Suite

The benefits of Adobe Software is ironically where confusion can potentially occur. At once each software platform has a forte, a privilege set of criteria from its workspace/interface design, its management, tools, asset handling, etc., there is also a high degree of overlap and commonality amongst each software package.

This aspect makes file and asset compatibility across Adobe Software simple, easy and enjoyable to work with, while also allowing for minor adjustment to be made locally rather than through an assets native, or prefered, software platform - i.e. line art or vector content can be made within Photoshop even though this software platform privileges raster content. The confusion can occur when a user silo’s any one software package within Adobe Systems/Suite rather than understanding that each and every software package is meant to work seamlessly with each other and content creation should be done relative to type and platform compatibility.

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Raster vector, static and dynamic organizational criteria

For the purposes of this field guide, it will primarily focus on four of the core Adobe software platforms of:Illustrator, Photoshop, Indesign and Bridge, approaching them through the criteria defined above and respective of their forte’s of Vector (Illustrator), Raster (Photoshop), Collating (Indesign), Managing (Bridge).