Raster vs. Vector Graphics

Raster Graphics

Raster graphics are rendered as bitmaps, which are grids of hundreds of tiny pixels that collectively form an image. They display rich color detail and will be your best choice when working with photographs.

Raster graphics cannot be enlarged without losing quality and appearing blurry. This is because each is defined and displayed at a specific resolution, or DPI (you can learn more about this on our blog post here).

You can use Adobe Photoshop to create and edit raster files, which will typically have the extensions .jpeg, .psd, .png, .tiff, .bmp, or .gif.

Vector Graphics

Vector graphics are made up of geometric shapes such as points, lines, and curves. Mathematical formulas are used to fill in color along these paths. They’re best used for fonts and logo designs.

Because they’re not dependent on resolution, vector graphics can be scaled up or down without losing quality. They’ll also create smaller file sizes. Some possible downsides are that they display limited color details and cannot handle effects such as blurring, drop shadows, etc.

Vector graphics are created and edited in Adobe Photoshop and will produce files with the extensions .eps, .ai, and .pdf.

to summarize ...

Raster

Good for: photographs
Software: Adobe Photoshop
Files: .jpeg, .psd, .png, .tiff, .bmp, .gif
Pros: rich color detail
Cons: blurry when enlarged; large file sizes

Vector

Good for: fonts, logos
Software: Adobe Illustrator
Files: .eps, .ai, .pdf
Pros: can be scaled up or down without losing quality; smaller file sizes; editable
Cons: limited color detail; limited effects

What File Format Should You Use?

Ever wondered what’s the best file format to use when saving an image? The answer will be different depending on what your image is used for. Before we explain some common file types, here are some general file types and terms:

• If the images are for the web, you’ll typically want to use JPEG, PNG, or GIF.
• TIFF files create high-quality images that can be used for print.
• If you want to keep an editable version, use your software’s native format — .psd for Photoshop, .ai for Illustrator, etc. It’s helpful to have this to send to your designer or printer.

COMPRESSION: Lossless compression does not lose visual information. The quality of the image will remain the same no matter how many times the file is decompressed and recompressed. 

Lossy compression loses visual information. The quality is reduced every time a file is decompressed and recompressed. The advantage of lossy compression techniques is that files can be made much smaller, which his helpful for sending files via email or posting them online.

File Types

JPEG — .jpg

JPEG may be the most commonly used and widely accepted image format, and it’s considered the standard for posting images online. It uses a lossy compression technique, resulting in small file sizes and fast load times. These files offer a good middle ground between quality and size.

GIF — .gif

GIF is another popular format used on the web. It uses lossless compression, and creates relatively small file sizes. However, it uses the 8-bit palette with only 256 colors (making JPEG the more popular choice). Unlike JPEGs, GIFs can use animation effects and support transparency.

PNG — .png

PNG was designed specifically for the web, and was intended as a replacement for the GIF. It uses a lossless compression technique, and saves color more efficiently than GIFs. While PNGs create larger file sizes than JPEGs, they support transparent (unlike GIFs). Because it uses RGB color rather than CMYK, it’s not the best choice for print.

TIFF — .tif

TIFF is a popular file type used in photo and page layout softwares (such as Photoshop, InDesign, and Quark). It creates very large file sizes and contains a lot of image data, with flexible color support for grayscale, CMYK, and RGB. It can be either lossless or lossy compression.

PDF

PDF is a universal file format developed by Adobe that can be opened by anyone with the free Adobe Reader software. PDFs can be saved as editable files, and they preserve all the fonts, layout, and both vector (lossless) and bitmap (lossy) graphics. They’re great for both digital and print. While the images aren’t embedded directly on websites, they can be offered as downloadable files.

Adobe Photoshop and Illustrator files – .PSD, .AI

A PSD is the native file format of Adobe Photoshop, and an AI file is the native format of Adobe Illustrator. They’re what you’ll use any time you’re working on an ongoing project in either program, and you should use these formats if you want to keep editable file versions. They use lossless compression.

Understanding Resolution

When you send us a file to be printed, it’s helpful to understand proper resolution. Printed images require much higher resolutions than on-screen images, and it’s best to have the proper settings from the beginning — because while we can always make the image smaller, we cannot go up in size without losing quality. To achieve a crisp, clear, and detailed final product, here’s what you need to know.

important terms

The DPI is the number of dots in a printed inch. The larger the DPI number, the greater the resolution, which means you’ll be able to see more detail. Printers produce images with tiny dots that mix CMYK colors, and the more dots per inch — or the less space there is between these dots — the crisper your final product will be.

You may also see the term PPI used, which stands for “pixels per inch.” PPI typically refers to on-screen images, whereas DPI applies to printing, but some people use them interchangeably.

how to set your DPI

You can set your DPI by changing the “Resolution” number when creating a new file in Photoshop. 300DPI is the standard for most high-quality prints, and 150DPI is generally the minimum.

(While you’re here, make sure you’re using the proper color mode and that the canvas dimensions are not too small for your print job. As stated above, it’s hard to go up in size without losing quality, so a file for a poster print, for example, should not be 2x5”.)

web vs. print

Web images typically have smaller resolutions, in order to allow for faster load times. It’s not really necessary to have a high resolution for web — the quality looks fine at 72DPI, which is the standard. So basically, you may want to have two separate files for print and web that are optimized accordingly.

in conclusion...

Always keep in mind that digital and printed images differ in a number of ways. A detailed, high-quality on-screen image will not necessarily translate well to print. If the resolution is too small, the final product may appear blurry or pixelated.

Again, it’s best to use the proper settings from the beginning, when you first create your file. Contact us if you have any questions.

Setting Up a Print Bleed

Whenever you’re creating a file to be printed, it’s important to include a bleed area in your design. A “bleed” allows us to account for any slight movement or mechanical variations when we’re cutting your cardstock. It serves as a buffer area, essentially. 

In the image above, there's a safety line (the dotted line) and a cut line. Anything outside the safety line, in the bleed area, may get cut off during the trimming process. You should keep all of your important text and images inside the dotted lines.

To ensure that there are no unprinted edges in the final trimmed product, all background colors or artwork should extend past the cutline to fill the bleed area (the blue area in the above image). If you send us a file for your business card that has a background and you don’t include a bleed, this may potentially result in a white edge on your card.

A 1/4-inch bleed will give us sufficient room to work with. If you look at the image above, this includes everything from the dotted safety line through the blue bleed area. The cut line measures 3.5" x 2" (standard U.S. business card size); the bleed area extends 1/8 of an inch past the cut line, and the safety area is an additional 1/8 of an inch inside the cutline. Using these guidelines, the file you send us should be 3.75" x 2.25".

Adobe InDesign and Illustrator allow you to specify the bleed amount for each side when you set up a new file. For Photoshop, we recommend checking out this tutorial video or downloading our template below. If you'd like to see the safe area, trim line and bleed area as you're creating your design, download one of our templates below.

download:

Adobe Illustrator Template
Adobe Photoshop Template

Questions? Don't hesitate to get in touch.