HELP! How do I know what file type I need??
We’ve all been there… anxiously hovering our fingers over the ‘send’ button on a reply email that reads ‘sorry… but what’s an EPS file?’
Holding your breath, waiting for the response that you imagine will have a snarky tone to it, as if to say, ‘are you serious?’
The truth is, unless you’re a graphic designer, chances are you’ve never needed to understand what these acronyms mean, and, I’ll let you in on a little secret – you actually don’t ever need to.
When trying to get things printed, however, it can be helpful to know which file types you’re going to need, or at least, how to get them. But don’t worry, there is a method to the madness, and we want to make that method ASAP (as simple as possible) to understand 😉.
Raster Files:
Raster image files are constructed using a set number of pixels, or individual-coloured blocks, that combine to form an image. The number and size of pixels used within an image will be determined by their resolution (high-res or low-res), and once that size is determined, they cannot be stretched without becoming distorted.
Have you ever tried to print an image off your iPhone onto a large canvas? Did it come out blurry? That’s because mobile phones convert images to raster files to minimise storage for quick loading. This means the pixels that combine to make an image on your phone are small, which makes them suitable for viewing on a phone screen, but impossible to blow up without losing image quality.
Vector Files:
Vector files, on the other hand, are constructed using proportional formulas (points on a grid), rather than pixels. This means they are far more flexible and can be infinitely resized. Vector files, therefore, are super handy for printing companies like ours so we can print your images to the best quality possible. If you’re having trouble creating or tracking down a vector version of your logo, talk to us to see if we have kept one in our records.
NOTE: These categories aren’t laws. The type of file (vector or raster) that is created depends on the program that it was created in. For example, EPS files can be pixel files if they’re saved in photoshop.
High-res vs. Low-res?
The difference between a high-resolution image and a low-resolution image is pixel density. Graphic designers measure resolution by either DPI (dots per inch), or PPI (pixels per inch). Website images won’t typically require a high resolution, but images used for print will. Websites typically display images at 72dpi, while printing requires no less than 300dpi.
But you can’t teach a cat how to bark. If an image doesn’t have enough pixels, it won’t be suitable for print. The only option is to retake the image at a higher resolution or find a better-quality image!
Types of Raster Files:
JPEG or JPG (Joint Photographic Experts Group)
You won’t have to beg for a JPEG!
JPEG’s are extremely common. JPEG’s are great for images on the web, in documents, or for projects that require printing at a high resolution. However, the quality of the image will always decrease as the file size is decreased, so always pay close attention to the resolution (dpi or ppi) and the file size when you’re using a JPEG for a printing project.
PNG (Portable Network Graphics)
Don’t print with a PNG
PNG’s are the perfect file type for editing and for use on web pages, but produce terrible printing outcomes. This is because PNG’s are low resolution. Despite their low resolution, they are great for use on the web due to their ability to save an image with more colours on a transparent background, making for high quality, sharp website images.
GIF (Graphics Interchange Format)
Ahhh, the moving picture!
GIF’s are just animated images, or at least, they can be. Unlike the JPEG and the PNG, GIF’s have a special feature that allows them to become animated as well. GIF files can hold multiple pictures at once, and, in a similar fashion to a flipbook, it was discovered that these images could be loaded sequentially to create a movement effect. They’re therefore super effective on the web as their small file size means they can load quickly, but limits their ability to produce a high-quality print.
TIFF (Tagged Image File)
You can’t tee off a TIFF.
It doesn’t matter how many times you copy, re-save, compress or stretch a TIFF, the quality of the original file will never be lost. However, because TIFF’s are still raster files, meaning they are composed of pixels, their ability to hold image quality results in very large files sizes. This means TIFF’s are not a good option to use on a webpage as they will seriously impact website performance due to their inability to load quickly. They are also not necessarily the best option for print. What TIFF’s are good at, however, is being edited. Most people will edit their images as a TIFF to ensure their image quality is not lost, and then save it as a JPEG when they’ve got their final version.
Types of Vector Files
PDF (Portable Document Format)
PDF is King.
PDF’s were invented by Adobe to transfer information from any application, on any computer, with anyone, anywhere. They are universal file types that retain quality and do not lose information. If you’re unsure about which file type to use, send a PDF. 9 times out of 10 it will be all you need. A PDF, however, CAN be a raster file, as the document can have images made of pixels within it.
EPS (Encapsulated Postscript)
EPS is a designer’s best friend.
EPS files were designed to produce high-resolution graphic images for print. Much like the PDF, they are universal in that any design software can open and edit them. EPS files may contain 2D Vector graphics, bitmap images and text, meaning designers are able to get all the information they need from the one file. They are a great option for printing, so always try to make sure you have one on hand!
AI (Adobe Illustrator Document)
Ai is the apple to a designer’s eye.
These types of files are super easy to manipulate and are suitable for all different kinds of uses on the web or print. They scale infinitely without losing image quality and are extremely versatile, allowing for layering and transparency where other file types don’t. They are also small files which makes them easy to open and share. Ai is by far the most preferred file type for any designer.
SVG (Scalable Vector Graphics)
SVG is Good for Google.
SVG files are unique in that they are written in XML code, meaning that they store information as coded text rather than as shapes. This means search engines can detect key words which can potentially rank a website higher in the search results. They are great for web graphics like logos, illustrations and charts but their lack of pixels makes using them for displaying high quality digital photos difficult.
Key Takeaways:
Spot the difference between a Raster and a Vector:
Raster files are made up of a set number of pixels, making them difficult to rescale, while vector files are made up of algorithms that make them infinitely scalable without losing image quality.
A file’s final category (raster or vector) is determined from the program used to create it.
For example, EPS files can be pixel files if they’re saved in photoshop.
If it ain’t high-res, it ain’t gonna print
While low-res images may be fine for use on websites, they do not make for high-quality printing. If you’re going to be printing an image, always ensure it is taken with a high-resolution camera.
PDF is King
A PDF will get you out of trouble 9 times out of 10. This is because PDF is a universal file type that can be opened on any type of computer with any application, and will retain image quality.
Designers love EPS and Ai Files
EPS and Ai files are vector files, meaning they are infinitely re-scalable. Designers love them because they are flexible and contain important information that helps match colours and sizes of images.