Vector based logo file formats - .ai and .eps format files

Vector based images SHOULD be the starting point of any logo design process. These images are created by High-End Drawing software such as Adobe Illustrator, Macromedia Freehand (now defunct) and Corel Draw and are the industry standard for any graphic design project. What are Vector based images? Simply put, Vector Images are incredibly small, scalable and editable images that allow designers unlimited freedom when it comes to logo design and illustration. Vector Files usually feature the file extensions .EPS, .AI .CDR and .SWF (used in Flash animations).

In absolute terms, a vector graphics file is your logo, broken down into a series of geometric shapes, consisting of outlines that are curved and joined at X Y coordinates or points. These coordinates and shape outlines are stored as mathematical equations (.EPS, .AI, .CDR formats) creating small and portable file sizes that are infinitely editable. In the simplest terms, you can imagine a Vector shape as a rubber band, wrapped around nails that have been pushed into a pegboard (see below). The Vector shapes work pretty well the same way. Move the nail and the 'rubber band' shape will change.

A close up of a Vector based image. You can view a Vector image as a series of rubber bands that are wrapped around points (similar to nails on a peg-board). Move these 'control' points and the outline of the shape will change.

Color and Vector file formats..

We now have a feel for what Vector shapes and images can be formed. But what about inside the Vectors? What about colors? Easy. Every Vector shape can be filled with a different color. That' s pretty well it. Of course, there are different kinds of colors that we can add - solid, screen and gradient - but the principle is always the same. What's the advantage of this? Because Vector shapes are based on mathematical equations, even colors are stored this way. Once this information is converted to numerical amounts of color your .eps file becomes exceptionally reliable when color matching and accuracy is a must. Because of this shape and color accuracy - Vector files are also used as your 'source files' - that is, the original artwork from which all other file formats can be created, including your electronic Pixel Based Images.

Vector based formats and 'spot color' reproduction..

The most common form of printing for Business Cards and Letterheads is spot color reproduction. Spot color printing uses per-mixed inks that are combined during the printing process to form the complete image. The is much more economical than full color (4 color process) printing but can, generally speaking, only be achieved when your logo is in Vector format.

Once our nifty new logo is setup as a two color design it is ready to print as a two spot color logo. This is the method you'll use when printing letterheads, business cards and other standard stationery design items. Using PREMIXED ink swatches (such as the Pantone Matching System), a designer, client or printer is able to select the exact color tones desired in a particular logo. This is very similar to selecting swatches of premixed paint to go on your wall at home. Your printer will take the file, and output a metal plate for each color. For instance, our nifty new logo uses 2 Pantone Spot colors, so our printer would make 2 plates - one for color 1 (PMS 185), the other for color 2(PMS BLACK). The plates are applied to the press, inked up with the appropriate color, and then the paper is run though the press, with one impression for each color. What comes out at the other side is your completed image. That's not to say that you MUST use spot colors if using a Vector version of your logo. You can use as many colors as you'd like, and the same basic premise applies. Above left is a version of our example logo, this time using red, black AND Orange. Just like our spot version it is adaptable and scalable (but would require four color process printing for traditional reproduction).

Screens and tones - a primer...

When working with your logo design, your designer may choose to add screens and tones of a particular color. If handled correctly, this should not be a concern - it will not increase the reproduction costs of your logo, while giving the appearance of more colors than we're actually using. Let's take a look at FIG 3. We've dropped two solid colors into our nifty new logo. Red (PMS 185) and Black. Now, we want to add a silver to the word logo. We can simply 'pour' a screen of Black into that Vector shape. This tone, or screen, is created with various sizes and densities of dots all made up of black. With a Vector based image, the physical size of the image does not matter - the sphere will be always be filled with the maximum resolution of dots. This feature of an Vector based image is a great advantage over Pixel Based Images, which are severely limited in the size at which they can be used.

If we want to add the impression of a third color, we can do this by using a percentage of one of the colors we're using. In this instance, we'll add gray to the word 'logo' in our design. By using a 'screen' of PMS BLACK, the logo will appear to feature a silver color, but we'll still only be paying for printing using 2 colors. Using screens of the various colors in your logo can add a new dimension, without adding expense.

Vector formats and the resolution issue.

When your nifty new logo is designed, you'll want to use it in a variety of sizes - some small, some large. Shouldn't be a problem - as long as you have a Vector based image to work with. Because VectorS are based on mathematical equations - they can be used at any size. Vector file formats ALWAYS output at the highest resolution of the device you're using to print with, so you'll always be assured of the best reproduction quality available.

Vector based versions of your logo can be enlarged without any image degradation (above left). Pixel based images must be used at the same size (or smaller) than the original 'source' file. If you attempt to enlarge a Pixel based image, it will Pixelate (the actual Pixels of the image will become vi sable). In practical terms, this will lead to your logo appearing 'blurry' (above right).

Pixel based images are a different issue. Because they are created using tightly packed Pixels, these images (.JPG, .TIF,. .BMP) must be in the resolution of the device that they're being used on. On a monitor that equates to 72 dpi (Pixels or Dots Per Inch), but in print that requirement balloons to a minimum of 266 dpi. What's the problem? Well, Pixel based images should not be enlarged (see above right) as the Pixels will be visible. Simply changing the print resolution of a72 dpi image to a 266 dpi image will NOT address this problem - you'll still end up with the effect seen in our diagram. What does this mean in real terms? Well, lets take an full screen image from the web at 600 Pixels wide at 72 dpi screen resolution. That translates to approximately 11 inches total width. When converted to 266 dpi that image can be only be used to a maximum of 3 inches wide in a traditional reproduction job such as letterhead and business card design(many printers require 300 dpi and that will further reduce our maximum size to 2.5 inches). How do we get around this? Simply scale our Vector image to the size required, and create a Pixel based image from that. The same principles apply to logos that use more than two colors as well. Here's a look at our example logo, this time featuring red, black AND orange and in a Pixel based format. If we try to enlarge it, the image degrades rather significantly.

So why do we need Pixel based images at all? Any form of electronic reproduction (i.e.: your web site) cannot use Vector based images (except for Flash logo design and animations) but requires Pixel based images such as .GIF and .JPGS. Because of the way they're created, Pixel based images lend themselves to special effects more readily (although this can create reproduction problems and a SKILLED designer can create special effects using Vector images). Also, many office software products utilize Pixel based images to import artwork. We still need Pixel based versions of our nifty new logo, but these should always begin life as our Vector image. Here's a full listing of what Vector based images and logo designs are capable of.