What’s So Great About Vector Art?

Many promotional products industry suppliers ask their distributors to send files in as “vector format”. It’s easy to take these things as the way things are and just pass the request on to the end-user client. But what’s so great about vector files to make so many suppliers request this format (and some even demand it!)?

The Easy Answer

To simplify things, vector art can be enlarged or reduced infinitely with no loss of sharpness. And doing so has no effect on the file size (meaning the amount of space it takes up on your computer — not the physical length & width of the document). On top of that, vector files have a very small file size compared to the pixel-based images.

To understand the real benefits of vector art, it helps to have a basic knowledge of image resolution. I have posted previously on that subject, so go check that out if you haven’t already.

Large or Small, It Does It All!

Instead of a grid of pixels, vector art uses mathematical formulas to render shapes. At the heart of this is what the graphic design industry refers to as Bézier curves — or sometimes just “curves”, “outlines”, or “paths”. Because these are based on mathematical formulas, they can be enlarged or reduced to any size from buttons to billboards.

For these reasons, any graphic designer worth their keep will design a logo with a vector version… so if you have an end-user with a professionally designed logo, there’s a strong chance that there’s a vector version of it somewhere in the world. Your client should have it, but even if they don’t, a quick call or email to the designer who created the logo should get a vector file on it’s way to you.

Our original artwork. Could be vector or raster.

Zooming in on a raster version reveals the "jaggies" or "stairsteps" that only get bigger as you zoom in further.

Vector art stays crisp no matter how far you zoom in or enlarge it.

Type Converted to Outlines

So you noticed those words, “curves” and “paths“? Many suppliers have asked you to send your files with type “converted to paths” (or curves or outlines). What this is refers to the ability of vector-based programs like Adobe Illustrator and CorelDRAW! to take live text and convert it to shapes built with Bézier curves.

The advantage here is that the art will look the same regardless of whether or not they have that particular font installed on their system. (It’s all too easy to forget to send along a font file with the art. And even if you remember, there are loads of potential problems that might pop up due to incompatible versions of software or corrupted files, etc.)

The caveat is this makes it so the text is no longer editable — you can’t use your cursor to select a word to correct spelling, etc. The letters are now just shapes like a digital version of letters cut out of paper. So many graphic artists choose to make a version of the file that maintains the live, editable text and another file with all the text converted to paths. At the very least, the conversion will be one of the last things the artist does before handing the file off to be printed.

File Formats

The most popular file format for vector art is probably the .eps (Encapsulated PostScript), which has been around since the 1980s. However, I’ve noticed in recent years that the use of .ai (Adobe Illustrator’s native format) has nearly caught up with the eps. There are other vector formats as well, but not nearly as widely used, and most vector-based software can create one or both of these file types.

One thing very important to keep in mind: just because a file is an .ai or .eps format doesn’t automatically mean it’s vector art. Both of these file types can contain both vector elements and raster elements… or any combination of the two.

(Sidebar Point: The popular JPEG format is raster-only, so there’s no guessing about that. If that’s what you have, you know there’s no vector about it.)

So it’s no wonder why a supplier would prefer vector art over raster:

• Smaller file sizes make the art more portable
• Infinite ability to enlarge/reduce the art to fit any imprint area
• Font problems nearly eliminated

Making Sense of Art Formats: Resolution

D.P.I.? Layered Files? Vector Art?

In the promotional products industry, art requirements sure have changed over the years. “Camera-Ready Art” has become an ancient term, and now we contend with things like “vector” art, or “resolution”, or RGB vs. CMYK, as well as many more. Distributors almost need a graphic art degree to even speak the language!

Hopefully I can take a few posts here to explain some of these things so you can better understand why one supplier might need your client’s logo sent in a different setup than another.

For this first post, I’ll talk about resolution. You get frequent requests for “high-rez” art… and most suppliers will define this as “300 dpi”. “DPI” simply means, “Dots Per Inch”, and it’s an indication of how much visual information is placed within a given physical dimension. In the digital age, we are really referring to “pixels per inch” when we are looking at our computers’ screens, and the “dots” come into play when the image or text gets imprinted onto a piece of paper or a promotional item. Yet we still hang onto the term, “dpi”, and use it interchangeably with “ppi”. I’ll be using “dpi” for this post just to keep things consistent.

A Grid of Tiny Squares

With the exception of vector art (more on that in a separate post), a digital image is divided into a grid of tiny squares. Each of these squares, or “pixels”, is assigned a solid color. Most images found on web sites are set at 72 dpi. Most images intended for print are set to 300 dpi.

Let’s say you have an image that’s three inches wide. It’s saved at 72 dpi. Three inches multiplied by 72 dpi gives us 216 pixels across the width of the image. Now take a different 3-inch-wide image that is set at 150 dpi. This second image will contain 450 pixels across the width. A third 3-inch-wide image at 300 dpi will have 900 pixels of information on the horizontal dimension.

Since each square is assigned a solid color, you can see how an inch of your image being divided into 300 squares can allow for a lot more detail than using only 72 squares in that inch.

But Wait! There’s More! (Or Not…)

So, if your image is divided up into 900 squares (300 dpi), and you tell the computer to make it 72 dpi (while maintaining the 3 inch physical dimension), the computer has to take 900 pieces if information and condense it down to 72 pieces of information. Obviously, doing so is going to involve compromises… and a lot of detail will get lost.

But the inverse is not true. (And this trips up many people — including some who’ve claimed to be “graphic artists”.) If your image is already a low-rez 72 dpi, and you try to increase it to 300 dpi, the computer can only take the information in that image and spread it across a higher number of pixels. Kinda like if you bake a pan of brownies. At first you make 2 cuts in one direction and two cuts in the other to give you nine brownies. But then you realize you have to feed more people , so you go back and make a cut in-between each of the previous cuts — 3 more cuts in each direction giving you 6 brownies across and 6 brownies down. Now you have 36 brownies, but you really don’t have “more”. When you try to go to a higher number in resolution on the computer, it is a very similar issue.

Two cuts in each direction gives us 9 brownies (pixels) per pan

More cuts make more brownies/pixels, but technically there's still the same amount of food.

But in the movies…

Okay, so you see these deals in the spy movies and TV shows where they get a photo that someone took with a regular digital camera from the top of a skyscraper and they keep zooming in and zooming in until they can read the numbers on the credit card held by a customer insude a store window 10 blocks away. I sure hope you know by now you can’t believe everything you see on the screen. There is just as much fantasy involved in a scene like this as there is in superheroes that can fly or reverse the earth’s rotation.

You can only zoom in so far before those squares get so big that they just look like the image shown earlier in this post. The computer can sometimes “guess” to add some pixels to fake things, but obviously not enough to generate numbers or letters or a recognizable human face when that information isn’t there to begin with.

Do the Math

Now, if you have a supplier telling you the imprint area for a given item is 3 inches square, and they need at least a 300 dpi image, you need to make sure your image is at least 900 pixels across. But what if you know your image is 10 inches square, but only 100 dpi. Does that render your file un-usable? Hardly. If you do the math, 10 inches x 100 dpi gives you 1000 pixels — more than enough for the imprint area. When you reduce the physical dimensions of your file, but keep the same pixel count, you are basically making all those pixels smaller, so more of them fit in an inch!

Hopefully this has shed some light on things for you. In my next post, I’ll be discussing the difference between vector art and “raster” art.