Pixelated Images: “Don’t Do That!” Episode 4
If you’re an event coordinator or product marketing manager, you’ve likely put together your share of PowerPoint presentations, helped design print brochures, and even worked on signage.
At one point or another, you’ve probably seen pixelated images or low-quality graphics turn up in your otherwise carefully constructed collateral. But you can prevent this by understanding what causes pixelation and how to prevent it.
Image Formats for Presentations, Print & More
So, let’s start with file formats because there are so many of them out there and we use a number of them on a daily basis.
Raster Formats Mean Pixelation: Bigger is Better
The four file types below are known as raster formats. A general rule of thumb when dealing with raster formats is bigger is better. That’s because raster formats work on the basis of pixels and the fewer pixels, the less flexibility you have.
Arguably the most well known file format for saving images, JPEG is considered a ‘lossy’ compression format, but with a mild compression there is no visible affect, especially on photographs. JPEG format does suffer from generational degradation when it is repeatedly edited and saved.
A widely accepted format as a photograph standard in the printing business, TIFF files can handle device-specific color spaces like the CMYK defined by a particular set of printing press inks.
This older and simplified format is best used for storing graphics with few colors such as logos and simple diagrams. Because it’s been around for so long it has universal software support and because it also has animation capabilities it is still widely used to provide motion, despite its low compression ratio compared to more modern video formats. Just check out www.giphy.com .
Originally created to be a free, open-source alternative to GIF, the PNG is durable and supports 8-bit through 48-bit truecolor with and without alpha channel (the alpha channel allows the white or black background to be a transparent background).
When you see an image that’s distorted or blurry the image has been stretched beyond its limits and the quality breaks down leaving you with a pixelated image.
Vector Images: Fully Scalable Graphics
Another graphic file format category is known as “vector.” We aren’t going to delve into the several varieties too deeply here, but this is what you need to know:
SVG, AI and CGM
Vector image formats contain a geometric description, which can be rendered smoothly at any desired display size (read: fully scalable graphics). Some common vector formats are SVG, AI, and CGM.
Mostly, the type of vector image files you’ll run into will be Adobe Illustrator files. Typically, you need the design program that the image was originally created in to view or edit vector files but there are some third party open source apps out there if you’re interested. (Check out Inkscape by Sourceforge.)
PDFs: Very Sharable
There is one last format we’re going to quickly touch on because of its recent use in the delivery of graphic files:
This file type was originally used for text documents that encapsulate text fields as well as other imported elements without having to use the original program used to create it. PDFs or Portable Document Format allow for the flexibility of sharing documents of all kinds with many people in a reasonable file size.
How to Choose The Right Image Format
Double check all your images–if you’re not sure how, find someone who is. You want to represent yourself and your company in the best light.
Place rasterized formats into a program like Adobe Illustrator and expect them to suddenly be vector images–it doesn’t work like that. By the same token, don’t expect to save a rasterized format as a vector format in hopes to enhance its scalability.
Try to use vector images wherever possible so that you have full control of the scalability. This is especially important for print jobs or images that will be projected onto a large screen.
Turn everything into a JPEG. You can definitely use the ‘Save As’ feature and create a JPEG alternative for sharing in an email, but remember to duplicate the original file first so you don’t save over it.
Know what file formats are best suited for a particular application. If you aren’t sure, ask someone who is-like your graphic designer.
Keep Multiple File Types of the Same Image
The biggest piece of advice we can leave you with is to always keep various file types of the same image on your workstation and know why you have them (and make sure they’re properly labeled).
If something is created in Illustrator make sure you have the JPEG and PNG versions as well.
Not only will that it give you flexibility if someone has a last minute request for a particular file, but if you have to send the Illustrator file out to someone, you can also attach a jpeg as a preview (in case that person doesn’t have Illustrator).
Remember, the images you share on your presentation materials represent your company. Don’t let low-quality images make a bad first impression.