Vector Vs. Raster

Vector or raster?

This might sound like a battle between two characters in an animated movie, but it’s actually an important question on image format.

Your shiny new logo has been created with great care and you want to make sure that it looks great whever it’s used. It needs to be reproduced consistently whether that’s on a leaflet, your website or a massive sign for your building.

If you’re working with a designer who didn’t design your logo, one of the first things they will ask is “can you supply a vector logo?”

What is a ‘vector’, what’s the deifference between ‘vector’ and ‘raster’ and why does it matter?

Raster

A ‘raster’ image is made up of a collection of coloured dots or pixels which, when viewed from a distance, form a picture. This is why the resolution of a raster image is described in dpi (dots per inch) or ppi (pixels per inch).

Digital photos are a common example of raster images. An iPhone 7 has a 12-megapixel camera, which means they can shoot images made up of 12-million colour pixels.

Raster images can be saved in multiple file formats: jpg/jpeg, psd, tiff, png, bmp and gif.

Pros:

Detail: Each pixel can be given a specific colour value, however subtle.

Precision: Each individual pixel can be edited (if you so desire). Colour, shade and intensity.

Cons:

Scaling: When a raster image is enlarged the pixels are also enlarged, or stetched. This can result in sharp and smooth edges becoming blurry or pixelated. Not a good look.

File size: One way around this scaling issue is to create a massive original image, which can then be shrunk down for other (smaller) uses. But, logos created at a large scale will generally result in huge file sizes. Try emailing that and still be on speaking terms with the recipient! Saving the logo as a JPEG with lots of compression might seem like a solution, but that can also have detrimental affects on your logo. The software used to export the JPEG will decide which pixels to merge sometimes creating a distracting pattern or discolouration.

Vector

Instead of trying to keep track of the millions of tiny pixels in a raster image, vector images describe a shape using points, lines and curves. These images are made up of paths that are infinitely scalable because they are based on algorithms rather than pixels. It’s clever stuff.

Vector images often have the file extension: ai, eps, svg or pdf.

You can see if the file is a vector by zooming in as much as you can. If the edges of your logo still look smooth, then you probbaly have a vector file.

Pros:

Scalable: The use of coordinates and other calculations to render the graphic means that it can be infinitely scaled with no loss of quality, even if you want to cover the side of a building with it.

File size: Limitless scaling with the same coordinates means much smaller file sizes.

Editable: They remain editable and can be edited with no loss of quality.

Cons:

Details: Replicating the colour depth and detail of the real world is impossible. If you need the real thing a photograph is the only solution.

Limitations: You lose the subtlety that you have with raster images.

Conclusion

If you want your logo to look as good as possible, wherever it’s used, you’ll need a vector file.

If you don’t have a vector version of your logo, don’t panic… it can be redrawn. If you need any assitance with that, we can help. Please get in touch.

Like what you see? Hire us.